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source: palm/trunk/SOURCE/wind_turbine_model_mod.f90 @ 3924

Last change on this file since 3924 was 3885, checked in by kanani, 6 years ago
restructure/add location/debug messages
Property svn:keywords set to `Id`
File size: 122.0 KB

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1	!> @file wind_turbine_model_mod.f90
2	!------------------------------------------------------------------------------!
3	! This file is part of the PALM model system.
4	!
5	! PALM is free software: you can redistribute it and/or modify it under the
6	! terms of the GNU General Public License as published by the Free Software
7	! Foundation, either version 3 of the License, or (at your option) any later
8	! version.
9	!
10	! PALM is distributed in the hope that it will be useful, but WITHOUT ANY
11	! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
12	! A PARTICULAR PURPOSE. See the GNU General Public License for more details.
13	!
14	! You should have received a copy of the GNU General Public License along with
15	! PALM. If not, see <http://www.gnu.org/licenses/>.
16	!
17	! Copyright 2009-2019 Carl von Ossietzky Universitaet Oldenburg
18	! Copyright 1997-2019 Leibniz Universitaet Hannover
19	!------------------------------------------------------------------------------!
20	!
21	! Current revisions:
22	! -----------------
23	!
24	!
25	! Former revisions:
26	! -----------------
27	! $Id: wind_turbine_model_mod.f90 3885 2019-04-11 11:29:34Z monakurppa $
28	! Changes related to global restructuring of location messages and introduction
29	! of additional debug messages
30	!
31	! 3875 2019-04-08 17:35:12Z knoop
32	! Addaped wtm_tendency to fit the module actions interface
33	!
34	! 3832 2019-03-28 13:16:58Z raasch
35	! instrumented with openmp directives
36	!
37	! 3725 2019-02-07 10:11:02Z raasch
38	! unused variables removed
39	!
40	! 3685 2019-01-21 01:02:11Z knoop
41	! Some interface calls moved to module_interface + cleanup
42	!
43	! 3655 2019-01-07 16:51:22Z knoop
44	! Replace degree symbol by 'degrees'
45	!
46	! 3274 2018-09-24 15:42:55Z knoop
47	! Modularization of all bulk cloud physics code components
48	!
49	! 3248 2018-09-14 09:42:06Z sward
50	! Minor formating changes
51	!
52	! 3246 2018-09-13 15:14:50Z sward
53	! Added error handling for input namelist via parin_fail_message
54	!
55	! 3241 2018-09-12 15:02:00Z raasch
56	! unused variables removed
57	!
58	! 3182 2018-07-27 13:36:03Z suehring
59	! Check for vertical stretching has been revised.
60	!
61	! 3139 2018-07-17 11:30:10Z Giersch
62	! Bugfix in calculation of alpha_attack
63	!
64	! 3069 2018-06-15 07:56:09Z witha
65	! Initialization of some arrays added
66	!
67	! 3066 2018-06-12 08:55:55Z Giersch
68	! Error message revised
69	!
70	! 3065 2018-06-12 07:03:02Z Giersch
71	! dz was replaced by dz(1), error message concerning grid stretching has been
72	! introduced
73	!
74	! 3049 2018-05-29 13:52:36Z Giersch
75	! Error messages revised
76	!
77	! 2932 2018-03-26 09:39:22Z Giersch
78	! renamed wind_turbine_par to wind_turbine_parameters
79	!
80	! 2894 2018-03-15 09:17:58Z Giersch
81	! variable named found has been introduced for checking if restart data was
82	! found, reading of restart strings has been moved completely to
83	! read_restart_data_mod, wind_turbine_prerun flag has been removed, redundant
84	! skipping function has been removed, wtm_read/write_restart_data have been
85	! renamed to wtm_r/wrd_global, wtm_rrd_global is called in
86	! read_restart_data_mod now, marker * end wtm * was removed, strings and
87	! their respective lengths are written out and read now in case of restart
88	! runs to get rid of prescribed character lengths, CASE DEFAULT was added if
89	! restart data is read
90	!
91	! 2885 2018-03-14 11:02:46Z Giersch
92	! Bugfix in interpolation of lift and drag coefficients on fine grid of radius
93	! segments and angles of attack, speed-up of the initialization of the wind
94	! turbine model
95	!
96	! 2792 2018-02-07 06:45:29Z Giersch
97	! omega_rot_l has to be calculated after determining the indices for the hub in
98	! case of restart runs
99	!
100	! 2776 2018-01-31 10:44:42Z Giersch
101	! wind_turbine_prerun flag is used to define if module
102	! related parameters were outputted as restart data
103	!
104	! 2718 2018-01-02 08:49:38Z maronga
105	! Corrected "Former revisions" section
106	!
107	! 2696 2017-12-14 17:12:51Z kanani
108	! Change in file header (GPL part)
109	!
110	! 2669 2017-12-06 16:03:27Z raasch
111	! filename of turbine output changed to WTM_OUTPUT_DATA. File extension now
112	! includes the nest domain number. Turbine extension changed to "_T##"
113	!
114	! 2576 2017-10-24 13:49:46Z Giersch
115	! Definition of a new function called wtm_skip_global to skip module
116	! parameters during reading restart data
117	!
118	! 2563 2017-10-19 15:36:10Z Giersch
119	! Restart runs with wind turbine model are possible now. For this purpose, two
120	! new subroutines wtm_write_restart_data and wtm_read_restart_data had to be
121	! defined
122	!
123	! 2553 2017-10-18 08:03:45Z Giersch
124	! Bugfix of vertical loop in wtm_tendencies to account for different turbine
125	! heights, bugfix of the interpolation of the u-component concerning the
126	! vertical index and further small adjustments of the programming style
127	!
128	! 2410 2017-09-06 08:16:30Z Giersch
129	! Revise error message PA0462
130	!
131	! 2349 2017-08-10 15:44:04Z Giersch
132	! Add parameter pitch_rate to namelist and revise/add error messages
133	!
134	! 2343 2017-08-08 11:28:43Z Giersch
135	! Unit correction in Doxygen comments
136	!
137	! 2323 2017-07-26 12:57:38Z Giersch
138	! Change unit number of file WTM_DATA from 201 to 90
139	!
140	! 2322 2017-07-26 08:30:28Z Giersch
141	! Bugfix of error message and assign error numbers
142	!
143	! 2257 2017-06-07 14:07:05Z witha
144	! Bugfix: turb_cl_tab and turb_cd_tab were set to zero before being allocated
145	!
146	! 2233 2017-05-30 18:08:54Z suehring
147	!
148	! 2232 2017-05-30 17:47:52Z suehring
149	! Adjustments to new topography concept
150	!
151	! 2152 2017-02-17 13:27:24Z lvollmer
152	! Bugfix in subroutine wtm_read_blade_tables
153	! Addition of a tip loss model
154	!
155	! 2015 2016-09-28 08:45:18Z lvollmer
156	! Bugfix of pitch control
157	!
158	! 2000 2016-08-20 18:09:15Z knoop
159	! Forced header and separation lines into 80 columns
160	!
161	! 1929 2016-06-09 16:25:25Z suehring
162	! Bugfix: added preprocessor directives for parallel and serial mode
163	!
164	! 1914 2016-05-26 14:44:07Z witha
165	! Initial revision
166	!
167	!
168	! Description:
169	! ------------
170	!> This module calculates the effect of wind turbines on the flow fields. The
171	!> initial version contains only the advanced actuator disk with rotation method
172	!> (ADM-R).
173	!> The wind turbines include the tower effect, can be yawed and tilted.
174	!> The wind turbine model includes controllers for rotational speed, pitch and
175	!> yaw.
176	!> Currently some specifications of the NREL 5 MW reference turbine
177	!> are hardcoded whereas most input data comes from separate files (currently
178	!> external, planned to be included as namelist which will be read in
179	!> automatically).
180	!>
181	!> @todo Replace dz(1) appropriatly to account for grid stretching
182	!> @todo Revise code according to PALM Coding Standard
183	!> @todo Implement ADM and ALM turbine models
184	!> @todo Generate header information
185	!> @todo Implement further parameter checks and error messages
186	!> @todo Revise and add code documentation
187	!> @todo Output turbine parameters as timeseries
188	!> @todo Include additional output variables
189	!> @todo Revise smearing the forces for turbines in yaw
190	!> @todo Revise nacelle and tower parameterization
191	!> @todo Allow different turbine types in one simulation
192	!
193	!------------------------------------------------------------------------------!
194	MODULE wind_turbine_model_mod
195
196	USE arrays_3d, &
197	ONLY: tend, u, v, w, zu, zw
198
199	USE basic_constants_and_equations_mod, &
200	ONLY: pi
201
202	USE control_parameters, &
203	ONLY: coupling_char, &
204	debug_output, &
205	dt_3d, dz, message_string, simulated_time, &
206	wind_turbine, initializing_actions
207
208	USE cpulog, &
209	ONLY: cpu_log, log_point_s
210
211	USE grid_variables, &
212	ONLY: ddx, dx, ddy, dy
213
214	USE indices, &
215	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nz, &
216	nzb, nzt, wall_flags_0
217
218	USE kinds
219
220	USE pegrid
221
222
223	IMPLICIT NONE
224
225	PRIVATE
226
227	!
228	!-- Variables specified in the namelist wind_turbine_par
229
230	INTEGER(iwp) :: nairfoils = 8 !< number of airfoils of the used turbine model (for ADM-R and ALM)
231	INTEGER(iwp) :: nturbines = 1 !< number of turbines
232
233	LOGICAL :: pitch_control = .FALSE. !< switch for use of pitch controller
234	LOGICAL :: speed_control = .FALSE. !< switch for use of speed controller
235	LOGICAL :: yaw_control = .FALSE. !< switch for use of yaw controller
236	LOGICAL :: tl_cor = .FALSE. !< switch for use of tip loss correct.
237
238	REAL(wp) :: segment_length = 1.0_wp !< length of the segments, the rotor area is divided into
239	!< (in tangential direction, as factor of MIN(dx,dy,dz))
240	REAL(wp) :: segment_width = 0.5_wp !< width of the segments, the rotor area is divided into
241	!< (in radial direction, as factor of MIN(dx,dy,dz))
242	REAL(wp) :: time_turbine_on = 0.0_wp !< time at which turbines are started
243	REAL(wp) :: tilt = 0.0_wp !< vertical tilt of the rotor [degree] ( positive = backwards )
244
245	REAL(wp), DIMENSION(1:100) :: dtow = 0.0_wp !< tower diameter [m]
246	REAL(wp), DIMENSION(1:100) :: omega_rot = 0.9_wp !< inital or constant rotor speed [rad/s]
247	REAL(wp), DIMENSION(1:100) :: phi_yaw = 0.0_wp !< yaw angle [degree] ( clockwise, 0 = facing west )
248	REAL(wp), DIMENSION(1:100) :: pitch_add = 0.0_wp !< constant pitch angle
249	REAL(wp), DIMENSION(1:100) :: rcx = 9999999.9_wp !< position of hub in x-direction
250	REAL(wp), DIMENSION(1:100) :: rcy = 9999999.9_wp !< position of hub in y-direction
251	REAL(wp), DIMENSION(1:100) :: rcz = 9999999.9_wp !< position of hub in z-direction
252	REAL(wp), DIMENSION(1:100) :: rnac = 0.0_wp !< nacelle diameter [m]
253	REAL(wp), DIMENSION(1:100) :: rr = 63.0_wp !< rotor radius [m]
254	! REAL(wp), DIMENSION(1:100) :: turb_cd_nacelle = 0.85_wp !< drag coefficient for nacelle
255	REAL(wp), DIMENSION(1:100) :: turb_cd_tower = 1.2_wp !< drag coefficient for tower
256
257	!
258	!-- Variables specified in the namelist for speed controller
259	!-- Default values are from the NREL 5MW research turbine (Jonkman, 2008)
260
261	REAL(wp) :: rated_power = 5296610.0_wp !< rated turbine power [W]
262	REAL(wp) :: gear_ratio = 97.0_wp !< Gear ratio from rotor to generator
263	REAL(wp) :: inertia_rot = 34784179.0_wp !< Inertia of the rotor [kg*m2]
264	REAL(wp) :: inertia_gen = 534.116_wp !< Inertia of the generator [kg*m2]
265	REAL(wp) :: gen_eff = 0.944_wp !< Electric efficiency of the generator
266	REAL(wp) :: gear_eff = 1.0_wp !< Loss between rotor and generator
267	REAL(wp) :: air_dens = 1.225_wp !< Air density to convert to W [kg/m3]
268	REAL(wp) :: rated_genspeed = 121.6805_wp !< Rated generator speed [rad/s]
269	REAL(wp) :: max_torque_gen = 47402.91_wp !< Maximum of the generator torque [Nm]
270	REAL(wp) :: slope2 = 2.332287_wp !< Slope constant for region 2
271	REAL(wp) :: min_reg2 = 91.21091_wp !< Lower generator speed boundary of region 2 [rad/s]
272	REAL(wp) :: min_reg15 = 70.16224_wp !< Lower generator speed boundary of region 1.5 [rad/s]
273	REAL(wp) :: max_trq_rate = 15000.0_wp !< Max generator torque increase [Nm/s]
274	REAL(wp) :: pitch_rate = 8.0_wp !< Max pitch rate [degree/s]
275
276
277	!
278	!-- Variables specified in the namelist for yaw control
279
280	REAL(wp) :: yaw_speed = 0.005236_wp !< speed of the yaw actuator [rad/s]
281	REAL(wp) :: max_miss = 0.08726_wp !< maximum tolerated yaw missalignment [rad]
282	REAL(wp) :: min_miss = 0.008726_wp !< minimum yaw missalignment for which the actuator stops [rad]
283
284	!
285	!-- Set flag for output files TURBINE_PARAMETERS
286	TYPE file_status
287	LOGICAL :: opened, opened_before
288	END TYPE file_status
289
290	TYPE(file_status), DIMENSION(500) :: openfile_turb_mod = &
291	file_status(.FALSE.,.FALSE.)
292
293	!
294	!-- Variables for initialization of the turbine model
295
296	INTEGER(iwp) :: inot !< turbine loop index (turbine id)
297	INTEGER(iwp) :: nsegs_max !< maximum number of segments (all turbines, required for allocation of arrays)
298	INTEGER(iwp) :: nrings_max !< maximum number of rings (all turbines, required for allocation of arrays)
299	INTEGER(iwp) :: ring !< ring loop index (ring number)
300	INTEGER(iwp) :: upper_end !<
301
302	INTEGER(iwp), DIMENSION(1) :: lct !<
303
304	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: i_hub !< index belonging to x-position of the turbine
305	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: i_smear !< index defining the area for the smearing of the forces (x-direction)
306	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: j_hub !< index belonging to y-position of the turbine
307	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: j_smear !< index defining the area for the smearing of the forces (y-direction)
308	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: k_hub !< index belonging to hub height
309	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: k_smear !< index defining the area for the smearing of the forces (z-direction)
310	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nrings !< number of rings per turbine
311	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nsegs_total !< total number of segments per turbine
312
313	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: nsegs !< number of segments per ring and turbine
314
315	!
316	!- parameters for the smearing from the rotor to the cartesian grid
317	REAL(wp) :: pol_a !< parameter for the polynomial smearing fct
318	REAL(wp) :: pol_b !< parameter for the polynomial smearing fct
319	REAL(wp) :: delta_t_factor !<
320	REAL(wp) :: eps_factor !<
321	REAL(wp) :: eps_min !<
322	REAL(wp) :: eps_min2 !<
323
324	!
325	!-- Variables for the calculation of lift and drag coefficients
326	REAL(wp), DIMENSION(:), ALLOCATABLE :: ard !<
327	REAL(wp), DIMENSION(:), ALLOCATABLE :: crd !<
328	REAL(wp), DIMENSION(:), ALLOCATABLE :: delta_r !< radial segment length
329	REAL(wp), DIMENSION(:), ALLOCATABLE :: lrd !<
330
331	REAL(wp) :: accu_cl_cd_tab = 0.1_wp !< Accuracy of the interpolation of
332	!< the lift and drag coeff [deg]
333
334	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cd_tab !< table of the blade drag coefficient
335	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cl_tab !< table of the blade lift coefficient
336
337	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: nac_cd_surf !< 3d field of the tower drag coefficient
338	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: tow_cd_surf !< 3d field of the nacelle drag coefficient
339
340	!
341	!-- Variables for the calculation of the forces
342
343	REAL(wp) :: cur_r !<
344	REAL(wp) :: phi_rotor !<
345	REAL(wp) :: pre_factor !<
346	REAL(wp) :: torque_seg !<
347	REAL(wp) :: u_int_l !<
348	REAL(wp) :: u_int_u !<
349	REAL(wp) :: u_rot !<
350	REAL(wp) :: v_int_l !<
351	REAL(wp) :: v_int_u !<
352	REAL(wp) :: w_int_l !<
353	REAL(wp) :: w_int_u !<
354	!$OMP THREADPRIVATE (cur_r, phi_rotor, pre_factor, torque_seg, u_int_l, u_int_u, u_rot, &
355	!$OMP& v_int_l, v_int_u, w_int_l, w_int_u)
356	!
357	!- Tendencies from the nacelle and tower thrust
358	REAL(wp) :: tend_nac_x = 0.0_wp !<
359	REAL(wp) :: tend_tow_x = 0.0_wp !<
360	REAL(wp) :: tend_nac_y = 0.0_wp !<
361	REAL(wp) :: tend_tow_y = 0.0_wp !<
362	!$OMP THREADPRIVATE (tend_nac_x, tend_tow_x, tend_nac_y, tend_tow_y)
363
364	REAL(wp), DIMENSION(:), ALLOCATABLE :: alpha_attack !<
365	REAL(wp), DIMENSION(:), ALLOCATABLE :: chord !<
366	REAL(wp), DIMENSION(:), ALLOCATABLE :: phi_rel !<
367	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_total !<
368	REAL(wp), DIMENSION(:), ALLOCATABLE :: thrust_rotor !<
369	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl !<
370	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd !<
371	REAL(wp), DIMENSION(:), ALLOCATABLE :: vrel !<
372	REAL(wp), DIMENSION(:), ALLOCATABLE :: vtheta !<
373
374	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: rbx, rby, rbz !< coordinates of the blade elements
375	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: rotx, roty, rotz !< normal vectors to the rotor coordinates
376
377	!
378	!- Fields for the interpolation of velocities on the rotor grid
379	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: u_int !<
380	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: u_int_1_l !<
381	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: v_int !<
382	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: v_int_1_l !<
383	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: w_int !<
384	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: w_int_1_l !<
385
386	!
387	!- rotor tendencies on the segments
388	REAL(wp), DIMENSION(:), ALLOCATABLE :: thrust_seg !<
389	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_seg_y !<
390	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_seg_z !<
391
392	!
393	!- rotor tendencies on the rings
394	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: thrust_ring !<
395	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: torque_ring_y !<
396	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: torque_ring_z !<
397
398	!
399	!- rotor tendencies on rotor grids for all turbines
400	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: thrust !<
401	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: torque_y !<
402	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: torque_z !<
403
404	!
405	!- rotor tendencies on coordinate grid
406	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_x !<
407	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_y !<
408	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_z !<
409	!
410	!- variables for the rotation of the rotor coordinates
411	REAL(wp), DIMENSION(1:100,1:3,1:3) :: rot_coord_trans !< matrix for rotation of rotor coordinates
412
413	REAL(wp), DIMENSION(1:3) :: rot_eigen_rad !<
414	REAL(wp), DIMENSION(1:3) :: rot_eigen_azi !<
415	REAL(wp), DIMENSION(1:3) :: rot_eigen_nor !<
416	REAL(wp), DIMENSION(1:3) :: re !<
417	REAL(wp), DIMENSION(1:3) :: rea !<
418	REAL(wp), DIMENSION(1:3) :: ren !<
419	REAL(wp), DIMENSION(1:3) :: rote !<
420	REAL(wp), DIMENSION(1:3) :: rota !<
421	REAL(wp), DIMENSION(1:3) :: rotn !<
422
423	!
424	!-- Fixed variables for the speed controller
425
426	LOGICAL :: start_up = .TRUE. !<
427
428	REAL(wp) :: Fcorner !< corner freq for the controller low pass filter
429	REAL(wp) :: min_reg25 !< min region 2.5
430	REAL(wp) :: om_rate !< rotor speed change
431	REAL(wp) :: slope15 !< slope in region 1.5
432	REAL(wp) :: slope25 !< slope in region 2.5
433	REAL(wp) :: trq_rate !< torque change
434	REAL(wp) :: vs_sysp !<
435	REAL(wp) :: lp_coeff !< coeff for the controller low pass filter
436
437	REAL(wp), DIMENSION(100) :: omega_rot_l = 0.0_wp !< local rot speed [rad/s]
438
439	!
440	!-- Fixed variables for the yaw controller
441
442	REAL(wp), DIMENSION(:) , ALLOCATABLE :: yawdir !< direction to yaw
443	REAL(wp), DIMENSION(:) , ALLOCATABLE :: phi_yaw_l !< local (cpu) yaw angle
444	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wd30_l !< local (cpu) long running avg of the wd
445	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wd2_l !< local (cpu) short running avg of the wd
446	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wdir !< wind direction at hub
447	REAL(wp), DIMENSION(:) , ALLOCATABLE :: u_inflow !< wind speed at hub
448	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wdir_l !<
449	REAL(wp), DIMENSION(:) , ALLOCATABLE :: u_inflow_l !<
450	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: wd30 !<
451	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: wd2 !<
452	LOGICAL, DIMENSION(1:100) :: doyaw = .FALSE. !<
453	INTEGER(iwp) :: WDLON !<
454	INTEGER(iwp) :: WDSHO !<
455
456	!
457	!-- Variables that have to be saved in the binary file for restarts
458	REAL(wp), DIMENSION(1:100) :: pitch_add_old = 0.0_wp !< old constant pitch angle
459	REAL(wp), DIMENSION(1:100) :: omega_gen = 0.0_wp !< curr. generator speed
460	REAL(wp), DIMENSION(1:100) :: omega_gen_f = 0.0_wp !< filtered generator speed
461	REAL(wp), DIMENSION(1:100) :: omega_gen_old = 0.0_wp !< last generator speed
462	REAL(wp), DIMENSION(1:100) :: omega_gen_f_old = 0.0_wp !< last filtered generator speed
463	REAL(wp), DIMENSION(1:100) :: torque_gen = 0.0_wp !< generator torque
464	REAL(wp), DIMENSION(1:100) :: torque_gen_old = 0.0_wp !< last generator torque
465
466
467	SAVE
468
469
470	INTERFACE wtm_parin
471	MODULE PROCEDURE wtm_parin
472	END INTERFACE wtm_parin
473
474	INTERFACE wtm_check_parameters
475	MODULE PROCEDURE wtm_check_parameters
476	END INTERFACE wtm_check_parameters
477
478	INTERFACE wtm_init_arrays
479	MODULE PROCEDURE wtm_init_arrays
480	END INTERFACE wtm_init_arrays
481
482	INTERFACE wtm_init
483	MODULE PROCEDURE wtm_init
484	END INTERFACE wtm_init
485
486	INTERFACE wtm_actions
487	MODULE PROCEDURE wtm_actions
488	MODULE PROCEDURE wtm_actions_ij
489	END INTERFACE wtm_actions
490
491	INTERFACE wtm_rrd_global
492	MODULE PROCEDURE wtm_rrd_global
493	END INTERFACE wtm_rrd_global
494
495	INTERFACE wtm_wrd_global
496	MODULE PROCEDURE wtm_wrd_global
497	END INTERFACE wtm_wrd_global
498
499
500	PUBLIC &
501	wtm_parin, &
502	wtm_check_parameters, &
503	wtm_init_arrays, &
504	wtm_init, &
505	wtm_actions, &
506	wtm_rrd_global, &
507	wtm_wrd_global
508
509
510	CONTAINS
511
512
513	!------------------------------------------------------------------------------!
514	! Description:
515	! ------------
516	!> Parin for &wind_turbine_par for wind turbine model
517	!------------------------------------------------------------------------------!
518	SUBROUTINE wtm_parin
519
520
521	IMPLICIT NONE
522
523	CHARACTER (LEN=80) :: line !< dummy string that contains the current line of the parameter file
524
525	NAMELIST /wind_turbine_par/ air_dens, dtow, gear_eff, gear_ratio, &
526	gen_eff, inertia_gen, inertia_rot, max_miss, &
527	max_torque_gen, max_trq_rate, min_miss, &
528	min_reg15, min_reg2, nairfoils, nturbines, &
529	omega_rot, phi_yaw, pitch_add, pitch_control,&
530	rated_genspeed, rated_power, rcx, rcy, rcz, &
531	rnac, rr, segment_length, segment_width, &
532	slope2, speed_control, tilt, time_turbine_on,&
533	turb_cd_tower, pitch_rate, &
534	yaw_control, yaw_speed, tl_cor
535	! , turb_cd_nacelle
536
537	NAMELIST /wind_turbine_parameters/ &
538	air_dens, dtow, gear_eff, gear_ratio, &
539	gen_eff, inertia_gen, inertia_rot, max_miss, &
540	max_torque_gen, max_trq_rate, min_miss, &
541	min_reg15, min_reg2, nairfoils, nturbines, &
542	omega_rot, phi_yaw, pitch_add, pitch_control,&
543	rated_genspeed, rated_power, rcx, rcy, rcz, &
544	rnac, rr, segment_length, segment_width, &
545	slope2, speed_control, tilt, time_turbine_on,&
546	turb_cd_tower, pitch_rate, &
547	yaw_control, yaw_speed, tl_cor
548	! , turb_cd_nacelle
549	!
550	!-- Try to find wind turbine model package
551	REWIND ( 11 )
552	line = ' '
553	DO WHILE ( INDEX( line, '&wind_turbine_parameters' ) == 0 )
554	READ ( 11, '(A)', END=12 ) line
555	ENDDO
556	BACKSPACE ( 11 )
557
558	!
559	!-- Read user-defined namelist
560	READ ( 11, wind_turbine_parameters, ERR = 10 )
561	!
562	!-- Set flag that indicates that the wind turbine model is switched on
563	wind_turbine = .TRUE.
564
565	GOTO 14
566
567	10 BACKSPACE( 11 )
568	READ( 11 , '(A)') line
569	CALL parin_fail_message( 'wind_turbine_parameters', line )
570
571	!
572	!-- Try to find wind turbine model package
573	12 REWIND ( 11 )
574	line = ' '
575	DO WHILE ( INDEX( line, '&wind_turbine_par' ) == 0 )
576	READ ( 11, '(A)', END=14 ) line
577	ENDDO
578	BACKSPACE ( 11 )
579
580	!
581	!-- Read user-defined namelist
582	READ ( 11, wind_turbine_par, ERR = 13, END = 14 )
583
584	message_string = 'namelist wind_tubrine_par is deprecated and will ' // &
585	'be removed in near future. &Please use namelist ' // &
586	'wind_turbine_parameters instead'
587	CALL message( 'wtm_parin', 'PA0487', 0, 1, 0, 6, 0 )
588
589	!
590	!-- Set flag that indicates that the wind turbine model is switched on
591	wind_turbine = .TRUE.
592
593	GOTO 14
594
595	13 BACKSPACE( 11 )
596	READ( 11 , '(A)') line
597	CALL parin_fail_message( 'wind_turbine_par', line )
598
599	14 CONTINUE ! TBD Change from continue, mit ierrn machen
600
601
602	END SUBROUTINE wtm_parin
603
604
605	!------------------------------------------------------------------------------!
606	! Description:
607	! ------------
608	!> This routine writes the respective restart data.
609	!------------------------------------------------------------------------------!
610	SUBROUTINE wtm_wrd_global
611
612
613	IMPLICIT NONE
614
615
616	CALL wrd_write_string( 'omega_gen' )
617	WRITE ( 14 ) omega_gen
618
619	CALL wrd_write_string( 'omega_gen_f' )
620	WRITE ( 14 ) omega_gen_f
621
622	CALL wrd_write_string( 'omega_gen_f_old' )
623	WRITE ( 14 ) omega_gen_f_old
624
625	CALL wrd_write_string( 'omega_gen_old' )
626	WRITE ( 14 ) omega_gen_old
627
628	CALL wrd_write_string( 'omega_rot' )
629	WRITE ( 14 ) omega_rot
630
631	CALL wrd_write_string( 'phi_yaw' )
632	WRITE ( 14 ) phi_yaw
633
634	CALL wrd_write_string( 'pitch_add' )
635	WRITE ( 14 ) pitch_add
636
637	CALL wrd_write_string( 'pitch_add_old' )
638	WRITE ( 14 ) pitch_add_old
639
640	CALL wrd_write_string( 'torque_gen' )
641	WRITE ( 14 ) torque_gen
642
643	CALL wrd_write_string( 'torque_gen_old' )
644	WRITE ( 14 ) torque_gen_old
645
646
647	END SUBROUTINE wtm_wrd_global
648
649
650	!------------------------------------------------------------------------------!
651	! Description:
652	! ------------
653	!> This routine reads the respective restart data.
654	!------------------------------------------------------------------------------!
655	SUBROUTINE wtm_rrd_global( found )
656
657
658	USE control_parameters, &
659	ONLY: length, restart_string
660
661
662	IMPLICIT NONE
663
664	LOGICAL, INTENT(OUT) :: found
665
666
667	found = .TRUE.
668
669
670	SELECT CASE ( restart_string(1:length) )
671
672	CASE ( 'omega_gen' )
673	READ ( 13 ) omega_gen
674	CASE ( 'omega_gen_f' )
675	READ ( 13 ) omega_gen_f
676	CASE ( 'omega_gen_f_old' )
677	READ ( 13 ) omega_gen_f_old
678	CASE ( 'omega_gen_old' )
679	READ ( 13 ) omega_gen_old
680	CASE ( 'omega_rot' )
681	READ ( 13 ) omega_rot
682	CASE ( 'phi_yaw' )
683	READ ( 13 ) phi_yaw
684	CASE ( 'pitch_add' )
685	READ ( 13 ) pitch_add
686	CASE ( 'pitch_add_old' )
687	READ ( 13 ) pitch_add_old
688	CASE ( 'torque_gen' )
689	READ ( 13 ) torque_gen
690	CASE ( 'torque_gen_old' )
691	READ ( 13 ) torque_gen_old
692
693	CASE DEFAULT
694
695	found = .FALSE.
696
697	END SELECT
698
699
700	END SUBROUTINE wtm_rrd_global
701
702
703	!------------------------------------------------------------------------------!
704	! Description:
705	! ------------
706	!> Check namelist parameter
707	!------------------------------------------------------------------------------!
708	SUBROUTINE wtm_check_parameters
709
710
711	IMPLICIT NONE
712
713	IF ( ( .NOT.speed_control ) .AND. pitch_control ) THEN
714	message_string = 'pitch_control = .TRUE. requires '// &
715	'speed_control = .TRUE.'
716	CALL message( 'wtm_check_parameters', 'PA0461', 1, 2, 0, 6, 0 )
717	ENDIF
718
719	IF ( ANY( omega_rot(1:nturbines) < 0.0 ) ) THEN
720	message_string = 'omega_rot < 0.0, Please set omega_rot to ' // &
721	'a value equal or larger than zero'
722	CALL message( 'wtm_check_parameters', 'PA0462', 1, 2, 0, 6, 0 )
723	ENDIF
724
725
726	IF ( ANY( rcx(1:nturbines) == 9999999.9_wp ) .OR. &
727	ANY( rcy(1:nturbines) == 9999999.9_wp ) .OR. &
728	ANY( rcz(1:nturbines) == 9999999.9_wp ) ) THEN
729
730	message_string = 'rcx, rcy, rcz ' // &
731	'have to be given for each turbine.'
732	CALL message( 'wtm_check_parameters', 'PA0463', 1, 2, 0, 6, 0 )
733
734	ENDIF
735
736
737	END SUBROUTINE wtm_check_parameters
738
739
740	!------------------------------------------------------------------------------!
741	! Description:
742	! ------------
743	!> Allocate wind turbine model arrays
744	!------------------------------------------------------------------------------!
745	SUBROUTINE wtm_init_arrays
746
747
748	IMPLICIT NONE
749
750	REAL(wp) :: delta_r_factor !<
751	REAL(wp) :: delta_r_init !<
752
753	!
754	!-- To be able to allocate arrays with dimension of rotor rings and segments,
755	!-- the maximum possible numbers of rings and segments have to be calculated:
756
757	ALLOCATE( nrings(1:nturbines) )
758	ALLOCATE( delta_r(1:nturbines) )
759
760	nrings(:) = 0
761	delta_r(:) = 0.0_wp
762
763	!
764	!-- Thickness (radial) of each ring and length (tangential) of each segment:
765	delta_r_factor = segment_width
766	delta_t_factor = segment_length
767	delta_r_init = delta_r_factor * MIN( dx, dy, dz(1))
768
769	DO inot = 1, nturbines
770	!
771	!-- Determine number of rings:
772	nrings(inot) = NINT( rr(inot) / delta_r_init )
773
774	delta_r(inot) = rr(inot) / nrings(inot)
775
776	ENDDO
777
778	nrings_max = MAXVAL(nrings)
779
780	ALLOCATE( nsegs(1:nrings_max,1:nturbines) )
781	ALLOCATE( nsegs_total(1:nturbines) )
782
783	nsegs(:,:) = 0
784	nsegs_total(:) = 0
785
786
787	DO inot = 1, nturbines
788	DO ring = 1, nrings(inot)
789	!
790	!-- Determine number of segments for each ring:
791	nsegs(ring,inot) = MAX( 8, CEILING( delta_r_factor * pi * &
792	( 2.0_wp * ring - 1.0_wp ) / &
793	delta_t_factor ) )
794	ENDDO
795	!
796	!-- Total sum of all rotor segments:
797	nsegs_total(inot) = SUM( nsegs(:,inot) )
798
799	ENDDO
800
801	!
802	!-- Maximum number of segments per ring:
803	nsegs_max = MAXVAL(nsegs)
804
805	!!
806	!!-- TODO: Folgendes im Header ausgeben!
807	! IF ( myid == 0 ) THEN
808	! PRINT*, 'nrings(1) = ', nrings(1)
809	! PRINT*, '--------------------------------------------------'
810	! PRINT*, 'nsegs(:,1) = ', nsegs(:,1)
811	! PRINT*, '--------------------------------------------------'
812	! PRINT*, 'nrings_max = ', nrings_max
813	! PRINT*, 'nsegs_max = ', nsegs_max
814	! PRINT*, 'nsegs_total(1) = ', nsegs_total(1)
815	! ENDIF
816
817
818	!
819	!-- Allocate 1D arrays (dimension = number of turbines)
820	ALLOCATE( i_hub(1:nturbines) )
821	ALLOCATE( i_smear(1:nturbines) )
822	ALLOCATE( j_hub(1:nturbines) )
823	ALLOCATE( j_smear(1:nturbines) )
824	ALLOCATE( k_hub(1:nturbines) )
825	ALLOCATE( k_smear(1:nturbines) )
826	ALLOCATE( torque_total(1:nturbines) )
827	ALLOCATE( thrust_rotor(1:nturbines) )
828
829	!
830	!-- Allocation of the 1D arrays for yaw control
831	ALLOCATE( yawdir(1:nturbines) )
832	ALLOCATE( u_inflow(1:nturbines) )
833	ALLOCATE( wdir(1:nturbines) )
834	ALLOCATE( u_inflow_l(1:nturbines) )
835	ALLOCATE( wdir_l(1:nturbines) )
836	ALLOCATE( phi_yaw_l(1:nturbines) )
837
838	!
839	!-- Allocate 1D arrays (dimension = number of rotor segments)
840	ALLOCATE( alpha_attack(1:nsegs_max) )
841	ALLOCATE( chord(1:nsegs_max) )
842	ALLOCATE( phi_rel(1:nsegs_max) )
843	ALLOCATE( thrust_seg(1:nsegs_max) )
844	ALLOCATE( torque_seg_y(1:nsegs_max) )
845	ALLOCATE( torque_seg_z(1:nsegs_max) )
846	ALLOCATE( turb_cd(1:nsegs_max) )
847	ALLOCATE( turb_cl(1:nsegs_max) )
848	ALLOCATE( vrel(1:nsegs_max) )
849	ALLOCATE( vtheta(1:nsegs_max) )
850
851	!
852	!-- Allocate 2D arrays (dimension = number of rotor rings and segments)
853	ALLOCATE( rbx(1:nrings_max,1:nsegs_max) )
854	ALLOCATE( rby(1:nrings_max,1:nsegs_max) )
855	ALLOCATE( rbz(1:nrings_max,1:nsegs_max) )
856	ALLOCATE( thrust_ring(1:nrings_max,1:nsegs_max) )
857	ALLOCATE( torque_ring_y(1:nrings_max,1:nsegs_max) )
858	ALLOCATE( torque_ring_z(1:nrings_max,1:nsegs_max) )
859
860	!
861	!-- Allocate additional 2D arrays
862	ALLOCATE( rotx(1:nturbines,1:3) )
863	ALLOCATE( roty(1:nturbines,1:3) )
864	ALLOCATE( rotz(1:nturbines,1:3) )
865
866	!
867	!-- Allocate 3D arrays (dimension = number of grid points)
868	ALLOCATE( nac_cd_surf(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
869	ALLOCATE( rot_tend_x(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
870	ALLOCATE( rot_tend_y(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
871	ALLOCATE( rot_tend_z(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
872	ALLOCATE( thrust(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
873	ALLOCATE( torque_y(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
874	ALLOCATE( torque_z(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
875	ALLOCATE( tow_cd_surf(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
876
877	!
878	!-- Allocate additional 3D arrays
879	ALLOCATE( u_int(1:nturbines,1:nrings_max,1:nsegs_max) )
880	ALLOCATE( u_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) )
881	ALLOCATE( v_int(1:nturbines,1:nrings_max,1:nsegs_max) )
882	ALLOCATE( v_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) )
883	ALLOCATE( w_int(1:nturbines,1:nrings_max,1:nsegs_max) )
884	ALLOCATE( w_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) )
885
886	!
887	!-- All of the arrays are initialized with a value of zero:
888	i_hub(:) = 0
889	i_smear(:) = 0
890	j_hub(:) = 0
891	j_smear(:) = 0
892	k_hub(:) = 0
893	k_smear(:) = 0
894
895	torque_total(:) = 0.0_wp
896	thrust_rotor(:) = 0.0_wp
897
898	IF ( TRIM( initializing_actions ) /= 'read_restart_data' ) THEN
899	omega_gen(:) = 0.0_wp
900	omega_gen_old(:) = 0.0_wp
901	omega_gen_f(:) = 0.0_wp
902	omega_gen_f_old(:) = 0.0_wp
903	pitch_add_old(:) = 0.0_wp
904	torque_gen(:) = 0.0_wp
905	torque_gen_old(:) = 0.0_wp
906	ENDIF
907
908	yawdir(:) = 0.0_wp
909	wdir_l(:) = 0.0_wp
910	wdir(:) = 0.0_wp
911	u_inflow(:) = 0.0_wp
912	u_inflow_l(:) = 0.0_wp
913	phi_yaw_l(:) = 0.0_wp
914
915	!
916	!-- Allocate 1D arrays (dimension = number of rotor segments)
917	alpha_attack(:) = 0.0_wp
918	chord(:) = 0.0_wp
919	phi_rel(:) = 0.0_wp
920	thrust_seg(:) = 0.0_wp
921	torque_seg_y(:) = 0.0_wp
922	torque_seg_z(:) = 0.0_wp
923	turb_cd(:) = 0.0_wp
924	turb_cl(:) = 0.0_wp
925	vrel(:) = 0.0_wp
926	vtheta(:) = 0.0_wp
927
928	rbx(:,:) = 0.0_wp
929	rby(:,:) = 0.0_wp
930	rbz(:,:) = 0.0_wp
931	thrust_ring(:,:) = 0.0_wp
932	torque_ring_y(:,:) = 0.0_wp
933	torque_ring_z(:,:) = 0.0_wp
934
935	rotx(:,:) = 0.0_wp
936	roty(:,:) = 0.0_wp
937	rotz(:,:) = 0.0_wp
938
939	nac_cd_surf(:,:,:) = 0.0_wp
940	rot_tend_x(:,:,:) = 0.0_wp
941	rot_tend_y(:,:,:) = 0.0_wp
942	rot_tend_z(:,:,:) = 0.0_wp
943	thrust(:,:,:) = 0.0_wp
944	torque_y(:,:,:) = 0.0_wp
945	torque_z(:,:,:) = 0.0_wp
946	tow_cd_surf(:,:,:) = 0.0_wp
947
948	u_int(:,:,:) = 0.0_wp
949	u_int_1_l(:,:,:) = 0.0_wp
950	v_int(:,:,:) = 0.0_wp
951	v_int_1_l(:,:,:) = 0.0_wp
952	w_int(:,:,:) = 0.0_wp
953	w_int_1_l(:,:,:) = 0.0_wp
954
955
956	END SUBROUTINE wtm_init_arrays
957
958
959	!------------------------------------------------------------------------------!
960	! Description:
961	! ------------
962	!> Initialization of the wind turbine model
963	!------------------------------------------------------------------------------!
964	SUBROUTINE wtm_init
965
966
967	USE control_parameters, &
968	ONLY: dz_stretch_level_start
969
970	IMPLICIT NONE
971
972	INTEGER(iwp) :: i !< running index
973	INTEGER(iwp) :: j !< running index
974	INTEGER(iwp) :: k !< running index
975
976	!
977	!-- Help variables for the smearing function
978	REAL(wp) :: eps_kernel !<
979
980	!
981	!-- Help variables for calculation of the tower drag
982	INTEGER(iwp) :: tower_n !<
983	INTEGER(iwp) :: tower_s !<
984
985	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: circle_points !<
986
987	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nacb !<
988	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nacl !<
989	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nacr !<
990	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nact !<
991
992	IF ( debug_output ) CALL debug_message( 'wtm_init', 'start' )
993
994	ALLOCATE( index_nacb(1:nturbines) )
995	ALLOCATE( index_nacl(1:nturbines) )
996	ALLOCATE( index_nacr(1:nturbines) )
997	ALLOCATE( index_nact(1:nturbines) )
998
999	!
1000	!------------------------------------------------------------------------------!
1001	!-- Calculation of parameters for the regularization kernel
1002	!-- (smearing of the forces)
1003	!------------------------------------------------------------------------------!
1004	!
1005	!-- In the following, some of the required parameters for the smearing will
1006	!-- be calculated:
1007
1008	!-- The kernel is set equal to twice the grid spacing which has turned out to
1009	!-- be a reasonable value (see e.g. Troldborg et al. (2013), Wind Energy,
1010	!-- DOI: 10.1002/we.1608):
1011	eps_kernel = 2.0_wp * dx
1012	!
1013	!-- The zero point (eps_min) of the polynomial function must be the following
1014	!-- if the integral of the polynomial function (for values < eps_min) shall
1015	!-- be equal to the integral of the Gaussian function used before:
1016	eps_min = ( 105.0_wp / 32.0_wp )*( 1.0_wp / 3.0_wp ) &
1017	pi*( 1.0_wp / 6.0_wp ) eps_kernel
1018	!
1019	!-- Stretching (non-uniform grid spacing) is not considered in the wind
1020	!-- turbine model. Therefore, vertical stretching has to be applied above
1021	!-- the area where the wtm is active. ABS (...) is required because the
1022	!-- default value of dz_stretch_level_start is -9999999.9_wp (negative).
1023	IF ( ABS( dz_stretch_level_start(1) ) <= MAXVAL(rcz(1:nturbines)) + &
1024	MAXVAL(rr(1:nturbines)) + &
1025	eps_min) THEN
1026	WRITE( message_string, * ) 'The lowest level where vertical ', &
1027	'stretching is applied &have to be ', &
1028	'greater than ',MAXVAL(rcz(1:nturbines)) +&
1029	MAXVAL(rr(1:nturbines)) + eps_min
1030	CALL message( 'wtm_init', 'PA0484', 1, 2, 0, 6, 0 )
1031	ENDIF
1032	!
1033	!-- Square of eps_min:
1034	eps_min2 = eps_min**2
1035	!
1036	!-- Parameters in the polynomial function:
1037	pol_a = 1.0_wp / eps_min**4
1038	pol_b = 2.0_wp / eps_min**2
1039	!
1040	!-- Normalization factor which is the inverse of the integral of the smearing
1041	!-- function:
1042	eps_factor = 105.0_wp / ( 32.0_wp * pi * eps_min**3 )
1043
1044	!-- Change tilt angle to rad:
1045	tilt = tilt * pi / 180.0_wp
1046
1047	!
1048	!-- Change yaw angle to rad:
1049	IF ( TRIM( initializing_actions ) /= 'read_restart_data' ) THEN
1050	phi_yaw(:) = phi_yaw(:) * pi / 180.0_wp
1051	ENDIF
1052
1053
1054	DO inot = 1, nturbines
1055	!
1056	!-- Rotate the rotor coordinates in case yaw and tilt are defined
1057	CALL wtm_rotate_rotor( inot )
1058
1059	!
1060	!-- Determine the indices of the hub height
1061	i_hub(inot) = INT( rcx(inot) / dx )
1062	j_hub(inot) = INT( ( rcy(inot) + 0.5_wp * dy ) / dy )
1063	k_hub(inot) = INT( ( rcz(inot) + 0.5_wp * dz(1) ) / dz(1) )
1064
1065	!
1066	!-- Determining the area to which the smearing of the forces is applied.
1067	!-- As smearing now is effectively applied only for distances smaller than
1068	!-- eps_min, the smearing area can be further limited and regarded as a
1069	!-- function of eps_min:
1070	i_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dx )
1071	j_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dy )
1072	k_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dz(1) )
1073
1074	ENDDO
1075
1076	!
1077	!-- Call the wtm_init_speed_control subroutine and calculate the local
1078	!-- omega_rot for the respective processor.
1079	IF ( speed_control) THEN
1080
1081	CALL wtm_init_speed_control
1082
1083	IF ( TRIM( initializing_actions ) == 'read_restart_data' ) THEN
1084
1085	DO inot = 1, nturbines
1086
1087	IF ( nxl > i_hub(inot) ) THEN
1088	torque_gen(inot) = 0.0_wp
1089	omega_gen_f(inot) = 0.0_wp
1090	omega_rot_l(inot) = 0.0_wp
1091	ENDIF
1092
1093	IF ( nxr < i_hub(inot) ) THEN
1094	torque_gen(inot) = 0.0_wp
1095	omega_gen_f(inot) = 0.0_wp
1096	omega_rot_l(inot) = 0.0_wp
1097	ENDIF
1098
1099	IF ( nys > j_hub(inot) ) THEN
1100	torque_gen(inot) = 0.0_wp
1101	omega_gen_f(inot) = 0.0_wp
1102	omega_rot_l(inot) = 0.0_wp
1103	ENDIF
1104
1105	IF ( nyn < j_hub(inot) ) THEN
1106	torque_gen(inot) = 0.0_wp
1107	omega_gen_f(inot) = 0.0_wp
1108	omega_rot_l(inot) = 0.0_wp
1109	ENDIF
1110
1111	IF ( ( nxl <= i_hub(inot) ) .AND. ( nxr >= i_hub(inot) ) ) THEN
1112	IF ( ( nys <= j_hub(inot) ) .AND. ( nyn >= j_hub(inot) ) ) THEN
1113
1114	omega_rot_l(inot) = omega_gen(inot) / gear_ratio
1115
1116	ENDIF
1117	ENDIF
1118
1119	END DO
1120
1121	ENDIF
1122
1123	ENDIF
1124
1125	!
1126	!------------------------------------------------------------------------------!
1127	!-- Determine the area within each grid cell that overlaps with the area
1128	!-- of the nacelle and the tower (needed for calculation of the forces)
1129	!------------------------------------------------------------------------------!
1130	!
1131	!-- Note: so far this is only a 2D version, in that the mean flow is
1132	!-- perpendicular to the rotor area.
1133
1134	!
1135	!-- Allocation of the array containing information on the intersection points
1136	!-- between rotor disk and the numerical grid:
1137	upper_end = ( ny + 1 ) * 10000
1138
1139	ALLOCATE( circle_points(1:2,1:upper_end) )
1140
1141	circle_points(:,:) = 0.0_wp
1142
1143
1144	DO inot = 1, nturbines ! loop over number of turbines
1145	!
1146	!-- Determine the grid index (u-grid) that corresponds to the location of
1147	!-- the rotor center (reduces the amount of calculations in the case that
1148	!-- the mean flow is perpendicular to the rotor area):
1149	i = i_hub(inot)
1150
1151	!
1152	!-- Determine the left and the right edge of the nacelle (corresponding
1153	!-- grid point indices):
1154	index_nacl(inot) = INT( ( rcy(inot) - rnac(inot) + 0.5_wp * dy ) / dy )
1155	index_nacr(inot) = INT( ( rcy(inot) + rnac(inot) + 0.5_wp * dy ) / dy )
1156	!
1157	!-- Determine the bottom and the top edge of the nacelle (corresponding
1158	!-- grid point indices).The grid point index has to be increased by 1, as
1159	!-- the first level for the u-component (index 0) is situated below the
1160	!-- surface. All points between z=0 and z=dz/s would already be contained
1161	!-- in grid box 1.
1162	index_nacb(inot) = INT( ( rcz(inot) - rnac(inot) ) / dz(1) ) + 1
1163	index_nact(inot) = INT( ( rcz(inot) + rnac(inot) ) / dz(1) ) + 1
1164
1165	!
1166	!-- Determine the indices of the grid boxes containing the left and
1167	!-- the right boundaries of the tower:
1168	tower_n = ( rcy(inot) + 0.5_wp * dtow(inot) - 0.5_wp * dy ) / dy
1169	tower_s = ( rcy(inot) - 0.5_wp * dtow(inot) - 0.5_wp * dy ) / dy
1170
1171	!
1172	!-- Determine the fraction of the grid box area overlapping with the tower
1173	!-- area and multiply it with the drag of the tower:
1174	IF ( ( nxlg <= i ) .AND. ( nxrg >= i ) ) THEN
1175
1176	DO j = nys, nyn
1177	!
1178	!-- Loop from south to north boundary of tower
1179	IF ( ( j >= tower_s ) .AND. ( j <= tower_n ) ) THEN
1180
1181	DO k = nzb, nzt
1182
1183	IF ( k == k_hub(inot) ) THEN
1184	IF ( tower_n - tower_s >= 1 ) THEN
1185	!
1186	!-- leftmost and rightmost grid box:
1187	IF ( j == tower_s ) THEN
1188	tow_cd_surf(k,j,i) = ( rcz(inot) - &
1189	( k_hub(inot) * dz(1) - 0.5_wp * dz(1) ) )*& ! extension in z-direction
1190	( ( tower_s + 1.0_wp + 0.5_wp ) * dy - &
1191	( rcy(inot) - 0.5_wp * dtow(inot) ) ) * & ! extension in y-direction
1192	turb_cd_tower(inot)
1193	ELSEIF ( j == tower_n ) THEN
1194	tow_cd_surf(k,j,i) = ( rcz(inot) - &
1195	( k_hub(inot) * dz(1) - 0.5_wp * dz(1) ) )*& ! extension in z-direction
1196	( ( rcy(inot) + 0.5_wp * dtow(inot) ) - &
1197	( tower_n + 0.5_wp ) * dy ) * & ! extension in y-direction
1198	turb_cd_tower(inot)
1199	!
1200	!-- grid boxes inbetween
1201	!-- (where tow_cd_surf = grid box area):
1202	ELSE
1203	tow_cd_surf(k,j,i) = ( rcz(inot) - &
1204	( k_hub(inot) * dz(1) - 0.5_wp * dz(1) ) )*&
1205	dy * turb_cd_tower(inot)
1206	ENDIF
1207	!
1208	!-- tower lies completely within one grid box:
1209	ELSE
1210	tow_cd_surf(k,j,i) = ( rcz(inot) - ( k_hub(inot) * &
1211	dz(1) - 0.5_wp * dz(1) ) ) * &
1212	dtow(inot) * turb_cd_tower(inot)
1213	ENDIF
1214	!
1215	!-- In case that k is smaller than k_hub the following actions
1216	!-- are carried out:
1217	ELSEIF ( k < k_hub(inot) ) THEN
1218
1219	IF ( ( tower_n - tower_s ) >= 1 ) THEN
1220	!
1221	!-- leftmost and rightmost grid box:
1222	IF ( j == tower_s ) THEN
1223	tow_cd_surf(k,j,i) = dz(1) * ( &
1224	( tower_s + 1 + 0.5_wp ) * dy - &
1225	( rcy(inot) - 0.5_wp * dtow(inot) ) &
1226	) * turb_cd_tower(inot)
1227	ELSEIF ( j == tower_n ) THEN
1228	tow_cd_surf(k,j,i) = dz(1) * ( &
1229	( rcy(inot) + 0.5_wp * dtow(inot) ) - &
1230	( tower_n + 0.5_wp ) * dy &
1231	) * turb_cd_tower(inot)
1232	!
1233	!-- grid boxes inbetween
1234	!-- (where tow_cd_surf = grid box area):
1235	ELSE
1236	tow_cd_surf(k,j,i) = dz(1) * dy * &
1237	turb_cd_tower(inot)
1238	ENDIF
1239	!
1240	!-- tower lies completely within one grid box:
1241	ELSE
1242	tow_cd_surf(k,j,i) = dz(1) * dtow(inot) * &
1243	turb_cd_tower(inot)
1244	ENDIF ! end if larger than grid box
1245
1246	ENDIF ! end if k == k_hub
1247
1248	ENDDO ! end loop over k
1249
1250	ENDIF ! end if inside north and south boundary of tower
1251
1252	ENDDO ! end loop over j
1253
1254	ENDIF ! end if hub inside domain + ghostpoints
1255
1256
1257	CALL exchange_horiz( tow_cd_surf, nbgp )
1258
1259	!
1260	!-- Calculation of the nacelle area
1261	!-- CAUTION: Currently disabled due to segmentation faults on the FLOW HPC
1262	!-- cluster (Oldenburg)
1263	!!
1264	!!-- Tabulate the points on the circle that are required in the following for
1265	!!-- the calculation of the Riemann integral (node points; they are called
1266	!!-- circle_points in the following):
1267	!
1268	! dy_int = dy / 10000.0_wp
1269	!
1270	! DO i_ip = 1, upper_end
1271	! yvalue = dy_int * ( i_ip - 0.5_wp ) + 0.5_wp * dy !<--- segmentation fault
1272	! sqrt_arg = rnac(inot)2 - ( yvalue - rcy(inot) )2 !<--- segmentation fault
1273	! IF ( sqrt_arg >= 0.0_wp ) THEN
1274	!!
1275	!!-- bottom intersection point
1276	! circle_points(1,i_ip) = rcz(inot) - SQRT( sqrt_arg )
1277	!!
1278	!!-- top intersection point
1279	! circle_points(2,i_ip) = rcz(inot) + SQRT( sqrt_arg ) !<--- segmentation fault
1280	! ELSE
1281	! circle_points(:,i_ip) = -111111 !<--- segmentation fault
1282	! ENDIF
1283	! ENDDO
1284	!
1285	!
1286	! DO j = nys, nyn
1287	!!
1288	!!-- In case that the grid box is located completely outside the nacelle
1289	!!-- (y) it can automatically be stated that there is no overlap between
1290	!!-- the grid box and the nacelle and consequently we can set
1291	!!-- nac_cd_surf(:,j,i) = 0.0:
1292	! IF ( ( j >= index_nacl(inot) ) .AND. ( j <= index_nacr(inot) ) ) THEN
1293	! DO k = nzb+1, nzt
1294	!!
1295	!!-- In case that the grid box is located completely outside the
1296	!!-- nacelle (z) it can automatically be stated that there is no
1297	!!-- overlap between the grid box and the nacelle and consequently
1298	!!-- we can set nac_cd_surf(k,j,i) = 0.0:
1299	! IF ( ( k >= index_nacb(inot) ) .OR. &
1300	! ( k <= index_nact(inot) ) ) THEN
1301	!!
1302	!!-- For all other cases Riemann integrals are calculated.
1303	!!-- Here, the points on the circle that have been determined
1304	!!-- above are used in order to calculate the overlap between the
1305	!!-- gridbox and the nacelle area (area approached by 10000
1306	!!-- rectangulars dz_int * dy_int):
1307	! DO i_ipg = 1, 10000
1308	! dz_int = dz
1309	! i_ip = j * 10000 + i_ipg
1310	!!
1311	!!-- Determine the vertical extension dz_int of the circle
1312	!!-- within the current grid box:
1313	! IF ( ( circle_points(2,i_ip) < zw(k) ) .AND. & !<--- segmentation fault
1314	! ( circle_points(2,i_ip) >= zw(k-1) ) ) THEN
1315	! dz_int = dz_int - & !<--- segmentation fault
1316	! ( zw(k) - circle_points(2,i_ip) )
1317	! ENDIF
1318	! IF ( ( circle_points(1,i_ip) <= zw(k) ) .AND. & !<--- segmentation fault
1319	! ( circle_points(1,i_ip) > zw(k-1) ) ) THEN
1320	! dz_int = dz_int - &
1321	! ( circle_points(1,i_ip) - zw(k-1) )
1322	! ENDIF
1323	! IF ( zw(k-1) > circle_points(2,i_ip) ) THEN
1324	! dz_int = 0.0_wp
1325	! ENDIF
1326	! IF ( zw(k) < circle_points(1,i_ip) ) THEN
1327	! dz_int = 0.0_wp
1328	! ENDIF
1329	! IF ( ( nxlg <= i ) .AND. ( nxrg >= i ) ) THEN
1330	! nac_cd_surf(k,j,i) = nac_cd_surf(k,j,i) + & !<--- segmentation fault
1331	! dy_int * dz_int * turb_cd_nacelle(inot)
1332	! ENDIF
1333	! ENDDO
1334	! ENDIF
1335	! ENDDO
1336	! ENDIF
1337	!
1338	! ENDDO
1339	!
1340	! CALL exchange_horiz( nac_cd_surf, nbgp ) !<--- segmentation fault
1341
1342	ENDDO ! end of loop over turbines
1343
1344	tow_cd_surf = tow_cd_surf / ( dx * dy * dz(1) ) ! Normalize tower drag
1345	nac_cd_surf = nac_cd_surf / ( dx * dy * dz(1) ) ! Normalize nacelle drag
1346
1347	CALL wtm_read_blade_tables
1348
1349	IF ( debug_output ) CALL debug_message( 'wtm_init', 'end' )
1350
1351	END SUBROUTINE wtm_init
1352
1353
1354	!------------------------------------------------------------------------------!
1355	! Description:
1356	! ------------
1357	!> Read in layout of the rotor blade , the lift and drag tables
1358	!> and the distribution of lift and drag tables along the blade
1359	!------------------------------------------------------------------------------!
1360	!
1361	SUBROUTINE wtm_read_blade_tables
1362
1363
1364	IMPLICIT NONE
1365
1366	INTEGER(iwp) :: ii !< running index
1367	INTEGER(iwp) :: jj !< running index
1368
1369	INTEGER(iwp) :: ierrn !<
1370
1371	CHARACTER(200) :: chmess !< Read in string
1372
1373	INTEGER(iwp) :: dlen !< no. rows of local table
1374	INTEGER(iwp) :: dlenbl !< no. rows of cd, cl table
1375	INTEGER(iwp) :: ialpha !< table position of current alpha value
1376	INTEGER(iwp) :: iialpha !<
1377	INTEGER(iwp) :: iir !<
1378	INTEGER(iwp) :: radres !< radial resolution
1379	INTEGER(iwp) :: t1 !< no. of airfoil
1380	INTEGER(iwp) :: t2 !< no. of airfoil
1381	INTEGER(iwp) :: trow !<
1382	INTEGER(iwp) :: dlenbl_int !< no. rows of interpolated cd, cl tables
1383
1384	REAL(wp) :: alpha_attack_i !<
1385	REAL(wp) :: weight_a !<
1386	REAL(wp) :: weight_b !<
1387
1388	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: ttoint1 !<
1389	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: ttoint2 !<
1390
1391	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd_sel1 !<
1392	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd_sel2 !<
1393	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl_sel1 !<
1394	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl_sel2 !<
1395	REAL(wp), DIMENSION(:), ALLOCATABLE :: read_cl_cd !< read in var array
1396
1397	REAL(wp), DIMENSION(:), ALLOCATABLE :: alpha_attack_tab !<
1398	REAL(wp), DIMENSION(:), ALLOCATABLE :: trad1 !<
1399	REAL(wp), DIMENSION(:), ALLOCATABLE :: trad2 !<
1400	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cd_table !<
1401	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cl_table !<
1402
1403	ALLOCATE ( read_cl_cd(1:2*nairfoils+1) )
1404
1405	!
1406	!-- Read in the distribution of lift and drag tables along the blade, the
1407	!-- layout of the rotor blade and the lift and drag tables:
1408
1409	OPEN ( 90, FILE='WTM_DATA', STATUS='OLD', FORM='FORMATTED', IOSTAT=ierrn )
1410
1411	IF ( ierrn /= 0 ) THEN
1412	message_string = 'file WTM_DATA does not exist'
1413	CALL message( 'wtm_init', 'PA0464', 1, 2, 0, 6, 0 )
1414	ENDIF
1415	!
1416	!-- Read distribution table:
1417
1418	dlen = 0
1419
1420	READ ( 90, '(3/)' )
1421
1422	rloop3: DO
1423	READ ( 90, *, IOSTAT=ierrn ) chmess
1424	IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop3
1425	dlen = dlen + 1
1426	ENDDO rloop3
1427
1428	ALLOCATE( trad1(1:dlen), trad2(1:dlen), ttoint1(1:dlen), ttoint2(1:dlen))
1429
1430	DO jj = 1,dlen+1
1431	BACKSPACE ( 90, IOSTAT=ierrn )
1432	ENDDO
1433
1434	DO jj = 1,dlen
1435	READ ( 90, * ) trad1(jj), trad2(jj), ttoint1(jj), ttoint2(jj)
1436	ENDDO
1437
1438	!
1439	!-- Read layout table:
1440
1441	dlen = 0
1442
1443	READ ( 90, '(3/)')
1444
1445	rloop1: DO
1446	READ ( 90, *, IOSTAT=ierrn ) chmess
1447	IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop1
1448	dlen = dlen + 1
1449	ENDDO rloop1
1450
1451	ALLOCATE( lrd(1:dlen), ard(1:dlen), crd(1:dlen) )
1452	DO jj = 1, dlen+1
1453	BACKSPACE ( 90, IOSTAT=ierrn )
1454	ENDDO
1455	DO jj = 1, dlen
1456	READ ( 90, * ) lrd(jj), ard(jj), crd(jj)
1457	ENDDO
1458
1459	!
1460	!-- Read tables (turb_cl(alpha),turb_cd(alpha) for the different profiles:
1461
1462	dlen = 0
1463
1464	READ ( 90, '(3/)' )
1465
1466	rloop2: DO
1467	READ ( 90, *, IOSTAT=ierrn ) chmess
1468	IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop2
1469	dlen = dlen + 1
1470	ENDDO rloop2
1471
1472	ALLOCATE( alpha_attack_tab(1:dlen), turb_cl_table(1:dlen,1:nairfoils), &
1473	turb_cd_table(1:dlen,1:nairfoils) )
1474
1475	DO jj = 1,dlen+1
1476	BACKSPACE ( 90, IOSTAT=ierrn )
1477	ENDDO
1478
1479	DO jj = 1,dlen
1480	READ ( 90, * ) read_cl_cd
1481	alpha_attack_tab(jj) = read_cl_cd(1)
1482	DO ii= 1, nairfoils
1483	turb_cl_table(jj,ii) = read_cl_cd(ii*2)
1484	turb_cd_table(jj,ii) = read_cl_cd(ii*2+1)
1485	ENDDO
1486
1487	ENDDO
1488
1489	dlenbl = dlen
1490
1491	CLOSE ( 90 )
1492
1493	!
1494	!-- For each possible radial position (resolution: 0.1 m --> 631 values if rr(1)=63m)
1495	!-- and each possible angle of attack (resolution: 0.1 degrees --> 3601 values!)
1496	!-- determine the lift and drag coefficient by interpolating between the
1497	!-- tabulated values of each table (interpolate to current angle of attack)
1498	!-- and between the tables (interpolate to current radial position):
1499
1500	ALLOCATE( turb_cl_sel1(1:dlenbl) )
1501	ALLOCATE( turb_cl_sel2(1:dlenbl) )
1502	ALLOCATE( turb_cd_sel1(1:dlenbl) )
1503	ALLOCATE( turb_cd_sel2(1:dlenbl) )
1504
1505	radres = INT( rr(1) * 10.0_wp ) + 1_iwp
1506	dlenbl_int = INT( 360.0_wp / accu_cl_cd_tab ) + 1_iwp
1507
1508	ALLOCATE( turb_cl_tab(1:dlenbl_int,1:radres) )
1509	ALLOCATE( turb_cd_tab(1:dlenbl_int,1:radres) )
1510
1511	DO iir = 1, radres ! loop over radius
1512
1513	cur_r = ( iir - 1_iwp ) * 0.1_wp
1514	!
1515	!-- Find position in table 1
1516	lct = MINLOC( ABS( trad1 - cur_r ) )
1517	! lct(1) = lct(1)
1518
1519	IF ( ( trad1(lct(1)) - cur_r ) .GT. 0.0 ) THEN
1520	lct(1) = lct(1) - 1
1521	ENDIF
1522
1523	trow = lct(1)
1524	!
1525	!-- Calculate weights for radius interpolation
1526	weight_a = ( trad2(trow) - cur_r ) / ( trad2(trow) - trad1(trow) )
1527	weight_b = ( cur_r - trad1(trow) ) / ( trad2(trow) - trad1(trow) )
1528	t1 = ttoint1(trow)
1529	t2 = ttoint2(trow)
1530
1531	IF ( t1 .EQ. t2 ) THEN ! if both are the same, the weights are NaN
1532	weight_a = 0.5_wp ! then do interpolate in between same twice
1533	weight_b = 0.5_wp ! using 0.5 as weight
1534	ENDIF
1535
1536	IF ( t1 == 0 .AND. t2 == 0 ) THEN
1537	turb_cd_sel1 = 0.0_wp
1538	turb_cd_sel2 = 0.0_wp
1539	turb_cl_sel1 = 0.0_wp
1540	turb_cl_sel2 = 0.0_wp
1541
1542	turb_cd_tab(1,iir) = 0.0_wp ! For -180 degrees (iialpha=1) the values
1543	turb_cl_tab(1,iir) = 0.0_wp ! for each radius has to be set
1544	! explicitly
1545	ELSE
1546	turb_cd_sel1 = turb_cd_table(:,t1)
1547	turb_cd_sel2 = turb_cd_table(:,t2)
1548	turb_cl_sel1 = turb_cl_table(:,t1)
1549	turb_cl_sel2 = turb_cl_table(:,t2)
1550	!
1551	!-- For -180 degrees (iialpha=1) the values for each radius has to be set
1552	!-- explicitly
1553	turb_cd_tab(1,iir) = ( weight_a * turb_cd_table(1,t1) + weight_b &
1554	* turb_cd_table(1,t2) )
1555	turb_cl_tab(1,iir) = ( weight_a * turb_cl_table(1,t1) + weight_b &
1556	* turb_cl_table(1,t2) )
1557	ENDIF
1558
1559	DO iialpha = 2, dlenbl_int ! loop over angles
1560
1561	alpha_attack_i = -180.0_wp + REAL( iialpha-1 ) * accu_cl_cd_tab
1562	ialpha = 1
1563
1564	DO WHILE ( ( alpha_attack_i > alpha_attack_tab(ialpha) ) .AND. (ialpha <= dlen ) )
1565	ialpha = ialpha + 1
1566	ENDDO
1567
1568	!
1569	!-- Interpolation of lift and drag coefficiencts on fine grid of radius
1570	!-- segments and angles of attack
1571
1572	turb_cl_tab(iialpha,iir) = ( alpha_attack_tab(ialpha) - &
1573	alpha_attack_i ) / &
1574	( alpha_attack_tab(ialpha) - &
1575	alpha_attack_tab(ialpha-1) ) * &
1576	( weight_a * turb_cl_sel1(ialpha-1) + &
1577	weight_b * turb_cl_sel2(ialpha-1) ) +&
1578	( alpha_attack_i - &
1579	alpha_attack_tab(ialpha-1) ) / &
1580	( alpha_attack_tab(ialpha) - &
1581	alpha_attack_tab(ialpha-1) ) * &
1582	( weight_a * turb_cl_sel1(ialpha) + &
1583	weight_b * turb_cl_sel2(ialpha) )
1584	turb_cd_tab(iialpha,iir) = ( alpha_attack_tab(ialpha) - &
1585	alpha_attack_i ) / &
1586	( alpha_attack_tab(ialpha) - &
1587	alpha_attack_tab(ialpha-1) ) * &
1588	( weight_a * turb_cd_sel1(ialpha-1) + &
1589	weight_b * turb_cd_sel2(ialpha-1) ) +&
1590	( alpha_attack_i - &
1591	alpha_attack_tab(ialpha-1) ) / &
1592	( alpha_attack_tab(ialpha) - &
1593	alpha_attack_tab(ialpha-1) ) * &
1594	( weight_a * turb_cd_sel1(ialpha) + &
1595	weight_b * turb_cd_sel2(ialpha) )
1596
1597	ENDDO ! end loop over angles of attack
1598
1599	ENDDO ! end loop over radius
1600
1601
1602	END SUBROUTINE wtm_read_blade_tables
1603
1604
1605	!------------------------------------------------------------------------------!
1606	! Description:
1607	! ------------
1608	!> The projection matrix for the coordinate system of therotor disc in respect
1609	!> to the yaw and tilt angle of the rotor is calculated
1610	!------------------------------------------------------------------------------!
1611	SUBROUTINE wtm_rotate_rotor( inot )
1612
1613
1614	IMPLICIT NONE
1615
1616	INTEGER(iwp) :: inot
1617	!
1618	!-- Calculation of the rotation matrix for the application of the tilt to
1619	!-- the rotors
1620	rot_eigen_rad(1) = SIN( phi_yaw(inot) ) ! x-component of the radial eigenvector
1621	rot_eigen_rad(2) = COS( phi_yaw(inot) ) ! y-component of the radial eigenvector
1622	rot_eigen_rad(3) = 0.0_wp ! z-component of the radial eigenvector
1623
1624	rot_eigen_azi(1) = 0.0_wp ! x-component of the azimuth eigenvector
1625	rot_eigen_azi(2) = 0.0_wp ! y-component of the azimuth eigenvector
1626	rot_eigen_azi(3) = 1.0_wp ! z-component of the azimuth eigenvector
1627
1628	rot_eigen_nor(1) = COS( phi_yaw(inot) ) ! x-component of the normal eigenvector
1629	rot_eigen_nor(2) = -SIN( phi_yaw(inot) ) ! y-component of the normal eigenvector
1630	rot_eigen_nor(3) = 0.0_wp ! z-component of the normal eigenvector
1631
1632	!
1633	!-- Calculation of the coordinate transformation matrix to apply a tilt to
1634	!-- the rotor. If tilt = 0, rot_coord_trans is a unit matrix.
1635
1636	rot_coord_trans(inot,1,1) = rot_eigen_rad(1)*2 &
1637	( 1.0_wp - COS( tilt ) ) + COS( tilt )
1638	rot_coord_trans(inot,1,2) = rot_eigen_rad(1) * rot_eigen_rad(2) * &
1639	( 1.0_wp - COS( tilt ) ) - &
1640	rot_eigen_rad(3) * SIN( tilt )
1641	rot_coord_trans(inot,1,3) = rot_eigen_rad(1) * rot_eigen_rad(3) * &
1642	( 1.0_wp - COS( tilt ) ) + &
1643	rot_eigen_rad(2) * SIN( tilt )
1644	rot_coord_trans(inot,2,1) = rot_eigen_rad(2) * rot_eigen_rad(1) * &
1645	( 1.0_wp - COS( tilt ) ) + &
1646	rot_eigen_rad(3) * SIN( tilt )
1647	rot_coord_trans(inot,2,2) = rot_eigen_rad(2)*2 &
1648	( 1.0_wp - COS( tilt ) ) + COS( tilt )
1649	rot_coord_trans(inot,2,3) = rot_eigen_rad(2) * rot_eigen_rad(3) * &
1650	( 1.0_wp - COS( tilt ) ) - &
1651	rot_eigen_rad(1) * SIN( tilt )
1652	rot_coord_trans(inot,3,1) = rot_eigen_rad(3) * rot_eigen_rad(1) * &
1653	( 1.0_wp - COS( tilt ) ) - &
1654	rot_eigen_rad(2) * SIN( tilt )
1655	rot_coord_trans(inot,3,2) = rot_eigen_rad(3) * rot_eigen_rad(2) * &
1656	( 1.0_wp - COS( tilt ) ) + &
1657	rot_eigen_rad(1) * SIN( tilt )
1658	rot_coord_trans(inot,3,3) = rot_eigen_rad(3)*2 &
1659	( 1.0_wp - COS( tilt ) ) + COS( tilt )
1660
1661	!
1662	!-- Vectors for the Transformation of forces from the rotor's spheric
1663	!-- coordinate system to the cartesian coordinate system
1664	rotx(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_nor )
1665	roty(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_rad )
1666	rotz(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_azi )
1667
1668	END SUBROUTINE wtm_rotate_rotor
1669
1670
1671	!------------------------------------------------------------------------------!
1672	! Description:
1673	! ------------
1674	!> Calculation of the forces generated by the wind turbine
1675	!------------------------------------------------------------------------------!
1676	SUBROUTINE wtm_forces
1677
1678
1679	IMPLICIT NONE
1680
1681	CHARACTER (LEN=4) :: turbine_id
1682
1683	INTEGER(iwp) :: i, j, k !< loop indices
1684	INTEGER(iwp) :: inot !< turbine loop index (turbine id)
1685	INTEGER(iwp) :: iialpha, iir !<
1686	INTEGER(iwp) :: rseg !<
1687	INTEGER(iwp) :: ring !<
1688	INTEGER(iwp) :: ii, jj, kk !<
1689
1690	REAL(wp) :: flag !< flag to mask topography grid points
1691	REAL(wp) :: sin_rot, cos_rot !<
1692	REAL(wp) :: sin_yaw, cos_yaw !<
1693
1694	REAL(wp) :: aa, bb, cc, dd !< interpolation distances
1695	REAL(wp) :: gg !< interpolation volume var
1696
1697	REAL(wp) :: dist_u_3d, dist_v_3d, dist_w_3d !< smearing distances
1698
1699
1700	!
1701	! Variables for pitch control
1702	LOGICAL :: pitch_sw = .FALSE.
1703
1704	INTEGER(iwp), DIMENSION(1) :: lct = 0
1705	REAL(wp), DIMENSION(1) :: rad_d = 0.0_wp
1706
1707	REAL(wp) :: tl_factor !< factor for tip loss correction
1708
1709
1710	CALL cpu_log( log_point_s(61), 'wtm_forces', 'start' )
1711
1712
1713	IF ( simulated_time >= time_turbine_on ) THEN
1714
1715	!
1716	!-- Set forces to zero for each new time step:
1717	thrust(:,:,:) = 0.0_wp
1718	torque_y(:,:,:) = 0.0_wp
1719	torque_z(:,:,:) = 0.0_wp
1720	torque_total(:) = 0.0_wp
1721	rot_tend_x(:,:,:) = 0.0_wp
1722	rot_tend_y(:,:,:) = 0.0_wp
1723	rot_tend_z(:,:,:) = 0.0_wp
1724	thrust_rotor(:) = 0.0_wp
1725	!
1726	!-- Loop over number of turbines:
1727	DO inot = 1, nturbines
1728
1729	cos_yaw = COS(phi_yaw(inot))
1730	sin_yaw = SIN(phi_yaw(inot))
1731	!
1732	!-- Loop over rings of each turbine:
1733
1734	!$OMP PARALLEL PRIVATE (ring, rseg, thrust_seg, torque_seg_y, torque_seg_z, sin_rot, &
1735	!$OMP& cos_rot, re, rbx, rby, rbz, ii, jj, kk, aa, bb, cc, dd, gg)
1736	!$OMP DO
1737	DO ring = 1, nrings(inot)
1738
1739	thrust_seg(:) = 0.0_wp
1740	torque_seg_y(:) = 0.0_wp
1741	torque_seg_z(:) = 0.0_wp
1742	!
1743	!-- Determine distance between each ring (center) and the hub:
1744	cur_r = (ring - 0.5_wp) * delta_r(inot)
1745
1746	!
1747	!-- Loop over segments of each ring of each turbine:
1748	DO rseg = 1, nsegs(ring,inot)
1749	!
1750	!-- !-----------------------------------------------------------!
1751	!-- !-- Determine coordinates of the ring segments --!
1752	!-- !-----------------------------------------------------------!
1753	!
1754	!-- Determine angle of ring segment towards zero degree angle of
1755	!-- rotor system (at zero degree rotor direction vectors aligned
1756	!-- with y-axis):
1757	phi_rotor = rseg * 2.0_wp * pi / nsegs(ring,inot)
1758	cos_rot = COS( phi_rotor )
1759	sin_rot = SIN( phi_rotor )
1760
1761	!-- Now the direction vectors can be determined with respect to
1762	!-- the yaw and tilt angle:
1763	re(1) = cos_rot * sin_yaw
1764	re(2) = cos_rot * cos_yaw
1765	re(3) = sin_rot
1766
1767	rote = MATMUL( rot_coord_trans(inot,:,:), re )
1768	!
1769	!-- Coordinates of the single segments (center points):
1770	rbx(ring,rseg) = rcx(inot) + cur_r * rote(1)
1771	rby(ring,rseg) = rcy(inot) + cur_r * rote(2)
1772	rbz(ring,rseg) = rcz(inot) + cur_r * rote(3)
1773
1774	!-- !-----------------------------------------------------------!
1775	!-- !-- Interpolation of the velocity components from the --!
1776	!-- !-- cartesian grid point to the coordinates of each ring --!
1777	!-- !-- segment (follows a method used in the particle model) --!
1778	!-- !-----------------------------------------------------------!
1779
1780	u_int(inot,ring,rseg) = 0.0_wp
1781	u_int_1_l(inot,ring,rseg) = 0.0_wp
1782
1783	v_int(inot,ring,rseg) = 0.0_wp
1784	v_int_1_l(inot,ring,rseg) = 0.0_wp
1785
1786	w_int(inot,ring,rseg) = 0.0_wp
1787	w_int_1_l(inot,ring,rseg) = 0.0_wp
1788
1789	!
1790	!-- Interpolation of the u-component:
1791
1792	ii = rbx(ring,rseg) * ddx
1793	jj = ( rby(ring,rseg) - 0.5_wp * dy ) * ddy
1794	kk = ( rbz(ring,rseg) + 0.5_wp * dz(1) ) / dz(1)
1795	!
1796	!-- Interpolate only if all required information is available on
1797	!-- the current PE:
1798	IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN
1799	IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN
1800
1801	aa = ( ( ii + 1 ) * dx - rbx(ring,rseg) ) * &
1802	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1803	bb = ( rbx(ring,rseg) - ii * dx ) * &
1804	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1805	cc = ( ( ii+1 ) * dx - rbx(ring,rseg) ) * &
1806	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1807	dd = ( rbx(ring,rseg) - ii * dx ) * &
1808	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1809	gg = dx * dy
1810
1811	u_int_l = ( aa * u(kk,jj,ii) + &
1812	bb * u(kk,jj,ii+1) + &
1813	cc * u(kk,jj+1,ii) + &
1814	dd * u(kk,jj+1,ii+1) &
1815	) / gg
1816
1817	u_int_u = ( aa * u(kk+1,jj,ii) + &
1818	bb * u(kk+1,jj,ii+1) + &
1819	cc * u(kk+1,jj+1,ii) + &
1820	dd * u(kk+1,jj+1,ii+1) &
1821	) / gg
1822
1823	u_int_1_l(inot,ring,rseg) = u_int_l + &
1824	( rbz(ring,rseg) - zu(kk) ) / dz(1) * &
1825	( u_int_u - u_int_l )
1826
1827	ELSE
1828	u_int_1_l(inot,ring,rseg) = 0.0_wp
1829	ENDIF
1830	ELSE
1831	u_int_1_l(inot,ring,rseg) = 0.0_wp
1832	ENDIF
1833
1834
1835	!
1836	!-- Interpolation of the v-component:
1837	ii = ( rbx(ring,rseg) - 0.5_wp * dx ) * ddx
1838	jj = rby(ring,rseg) * ddy
1839	kk = ( rbz(ring,rseg) + 0.5_wp * dz(1) ) / dz(1)
1840	!
1841	!-- Interpolate only if all required information is available on
1842	!-- the current PE:
1843	IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN
1844	IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN
1845
1846	aa = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1847	( ( jj + 1 ) * dy - rby(ring,rseg) )
1848	bb = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1849	( ( jj + 1 ) * dy - rby(ring,rseg) )
1850	cc = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1851	( rby(ring,rseg) - jj * dy )
1852	dd = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1853	( rby(ring,rseg) - jj * dy )
1854	gg = dx * dy
1855
1856	v_int_l = ( aa * v(kk,jj,ii) + &
1857	bb * v(kk,jj,ii+1) + &
1858	cc * v(kk,jj+1,ii) + &
1859	dd * v(kk,jj+1,ii+1) &
1860	) / gg
1861
1862	v_int_u = ( aa * v(kk+1,jj,ii) + &
1863	bb * v(kk+1,jj,ii+1) + &
1864	cc * v(kk+1,jj+1,ii) + &
1865	dd * v(kk+1,jj+1,ii+1) &
1866	) / gg
1867
1868	v_int_1_l(inot,ring,rseg) = v_int_l + &
1869	( rbz(ring,rseg) - zu(kk) ) / dz(1) * &
1870	( v_int_u - v_int_l )
1871
1872	ELSE
1873	v_int_1_l(inot,ring,rseg) = 0.0_wp
1874	ENDIF
1875	ELSE
1876	v_int_1_l(inot,ring,rseg) = 0.0_wp
1877	ENDIF
1878
1879
1880	!
1881	!-- Interpolation of the w-component:
1882	ii = ( rbx(ring,rseg) - 0.5_wp * dx ) * ddx
1883	jj = ( rby(ring,rseg) - 0.5_wp * dy ) * ddy
1884	kk = rbz(ring,rseg) / dz(1)
1885	!
1886	!-- Interpolate only if all required information is available on
1887	!-- the current PE:
1888	IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN
1889	IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN
1890
1891	aa = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1892	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1893	bb = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1894	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1895	cc = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1896	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1897	dd = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1898	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1899	gg = dx * dy
1900
1901	w_int_l = ( aa * w(kk,jj,ii) + &
1902	bb * w(kk,jj,ii+1) + &
1903	cc * w(kk,jj+1,ii) + &
1904	dd * w(kk,jj+1,ii+1) &
1905	) / gg
1906
1907	w_int_u = ( aa * w(kk+1,jj,ii) + &
1908	bb * w(kk+1,jj,ii+1) + &
1909	cc * w(kk+1,jj+1,ii) + &
1910	dd * w(kk+1,jj+1,ii+1) &
1911	) / gg
1912
1913	w_int_1_l(inot,ring,rseg) = w_int_l + &
1914	( rbz(ring,rseg) - zw(kk) ) / dz(1) * &
1915	( w_int_u - w_int_l )
1916	ELSE
1917	w_int_1_l(inot,ring,rseg) = 0.0_wp
1918	ENDIF
1919	ELSE
1920	w_int_1_l(inot,ring,rseg) = 0.0_wp
1921	ENDIF
1922
1923	ENDDO
1924	ENDDO
1925	!$OMP END PARALLEL
1926
1927	ENDDO
1928
1929	!
1930	!-- Exchange between PEs (information required on each PE):
1931	#if defined( __parallel )
1932	CALL MPI_ALLREDUCE( u_int_1_l, u_int, nturbines * MAXVAL(nrings) * &
1933	MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr )
1934	CALL MPI_ALLREDUCE( v_int_1_l, v_int, nturbines * MAXVAL(nrings) * &
1935	MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr )
1936	CALL MPI_ALLREDUCE( w_int_1_l, w_int, nturbines * MAXVAL(nrings) * &
1937	MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr )
1938	#else
1939	u_int = u_int_1_l
1940	v_int = v_int_1_l
1941	w_int = w_int_1_l
1942	#endif
1943
1944
1945	!
1946	!-- Loop over number of turbines:
1947
1948	DO inot = 1, nturbines
1949	pit_loop: DO
1950
1951	IF ( pitch_sw ) THEN
1952	torque_total(inot) = 0.0_wp
1953	thrust_rotor(inot) = 0.0_wp
1954	pitch_add(inot) = pitch_add(inot) + 0.25_wp
1955	! IF ( myid == 0 ) PRINT*, 'Pitch', inot, pitch_add(inot)
1956	ELSE
1957	cos_yaw = COS(phi_yaw(inot))
1958	sin_yaw = SIN(phi_yaw(inot))
1959	IF ( pitch_control ) THEN
1960	pitch_add(inot) = MAX(pitch_add_old(inot) - pitch_rate * &
1961	dt_3d , 0.0_wp )
1962	ENDIF
1963	ENDIF
1964
1965	!
1966	!-- Loop over rings of each turbine:
1967	!$OMP PARALLEL PRIVATE (ring, rseg, sin_rot, cos_rot, re, rea, ren, rote, rota, rotn, &
1968	!$OMP& vtheta, phi_rel, lct, rad_d, alpha_attack, vrel, &
1969	!$OMP& chord, iialpha, iir, turb_cl, tl_factor, thrust_seg, &
1970	!$OMP& torque_seg_y, turb_cd, torque_seg_z, thrust_ring, &
1971	!$OMP& torque_ring_y, torque_ring_z)
1972	!$OMP DO
1973	DO ring = 1, nrings(inot)
1974	!
1975	!-- Determine distance between each ring (center) and the hub:
1976	cur_r = (ring - 0.5_wp) * delta_r(inot)
1977	!
1978	!-- Loop over segments of each ring of each turbine:
1979	DO rseg = 1, nsegs(ring,inot)
1980	!
1981	!-- Determine angle of ring segment towards zero degree angle of
1982	!-- rotor system (at zero degree rotor direction vectors aligned
1983	!-- with y-axis):
1984	phi_rotor = rseg * 2.0_wp * pi / nsegs(ring,inot)
1985	cos_rot = COS(phi_rotor)
1986	sin_rot = SIN(phi_rotor)
1987	!
1988	!-- Now the direction vectors can be determined with respect to
1989	!-- the yaw and tilt angle:
1990	re(1) = cos_rot * sin_yaw
1991	re(2) = cos_rot * cos_yaw
1992	re(3) = sin_rot
1993
1994	! The current unit vector in azimuthal direction:
1995	rea(1) = - sin_rot * sin_yaw
1996	rea(2) = - sin_rot * cos_yaw
1997	rea(3) = cos_rot
1998
1999	!
2000	!-- To respect the yawing angle for the calculations of
2001	!-- velocities and forces the unit vectors perpendicular to the
2002	!-- rotor area in direction of the positive yaw angle are defined:
2003	ren(1) = cos_yaw
2004	ren(2) = - sin_yaw
2005	ren(3) = 0.0_wp
2006	!
2007	!-- Multiplication with the coordinate transformation matrix
2008	!-- gives the final unit vector with consideration of the rotor
2009	!-- tilt:
2010	rote = MATMUL( rot_coord_trans(inot,:,:), re )
2011	rota = MATMUL( rot_coord_trans(inot,:,:), rea )
2012	rotn = MATMUL( rot_coord_trans(inot,:,:), ren )
2013	!
2014	!-- Coordinates of the single segments (center points):
2015	rbx(ring,rseg) = rcx(inot) + cur_r * rote(1)
2016
2017	rby(ring,rseg) = rcy(inot) + cur_r * rote(2)
2018
2019	rbz(ring,rseg) = rcz(inot) + cur_r * rote(3)
2020
2021	!
2022	!-- !-----------------------------------------------------------!
2023	!-- !-- Calculation of various angles and relative velocities --!
2024	!-- !-----------------------------------------------------------!
2025	!
2026	!-- In the following the 3D-velocity field is projected its
2027	!-- components perpendicular and parallel to the rotor area
2028	!-- The calculation of forces will be done in the rotor-
2029	!-- coordinates y' and z.
2030	!-- The yaw angle will be reintroduced when the force is applied
2031	!-- on the hydrodynamic equations
2032	!
2033	!-- Projection of the xy-velocities relative to the rotor area
2034	!
2035	!-- Velocity perpendicular to the rotor area:
2036	u_rot = u_int(inot,ring,rseg)*rotn(1) + &
2037	v_int(inot,ring,rseg)*rotn(2) + &
2038	w_int(inot,ring,rseg)*rotn(3)
2039	!
2040	!-- Projection of the 3D-velocity vector in the azimuthal
2041	!-- direction:
2042	vtheta(rseg) = rota(1) * u_int(inot,ring,rseg) + &
2043	rota(2) * v_int(inot,ring,rseg) + &
2044	rota(3) * w_int(inot,ring,rseg)
2045	!
2046	!-- Determination of the angle phi_rel between the rotor plane
2047	!-- and the direction of the flow relative to the rotor:
2048
2049	phi_rel(rseg) = ATAN( u_rot / &
2050	( omega_rot(inot) * cur_r - &
2051	vtheta(rseg) ) )
2052
2053	!
2054	!-- Interpolation of the local pitch angle from tabulated values
2055	!-- to the current radial position:
2056
2057	lct=minloc(ABS(cur_r-lrd))
2058	rad_d=cur_r-lrd(lct)
2059
2060	IF (cur_r == 0.0_wp) THEN
2061	alpha_attack(rseg) = 0.0_wp
2062	ELSE IF (cur_r >= lrd(size(ard))) THEN
2063	alpha_attack(rseg) = ( ard(size(ard)) + &
2064	ard(size(ard)-1) ) / 2.0_wp
2065	ELSE
2066	alpha_attack(rseg) = ( ard(lct(1)) * &
2067	( ( lrd(lct(1)+1) - cur_r ) / &
2068	( lrd(lct(1)+1) - lrd(lct(1)) ) &
2069	) ) + ( ard(lct(1)+1) * &
2070	( ( cur_r - lrd(lct(1)) ) / &
2071	( lrd(lct(1)+1) - lrd(lct(1)) ) ) )
2072	ENDIF
2073
2074	!
2075	!-- In Fortran radian instead of degree is used as unit for all
2076	!-- angles. Therefore, a transformation from angles given in
2077	!-- degree to angles given in radian is necessary here:
2078	alpha_attack(rseg) = alpha_attack(rseg) * &
2079	( (2.0_wp*pi) / 360.0_wp )
2080	!
2081	!-- Substraction of the local pitch angle to obtain the local
2082	!-- angle of attack:
2083	alpha_attack(rseg) = phi_rel(rseg) - alpha_attack(rseg)
2084	!
2085	!-- Preliminary transformation back from angles given in radian
2086	!-- to angles given in degree:
2087	alpha_attack(rseg) = alpha_attack(rseg) * &
2088	( 360.0_wp / (2.0_wp*pi) )
2089	!
2090	!-- Correct with collective pitch angle:
2091	alpha_attack(rseg) = alpha_attack(rseg) - pitch_add(inot)
2092
2093	!
2094	!-- Determination of the magnitude of the flow velocity relative
2095	!-- to the rotor:
2096	vrel(rseg) = SQRT( u_rot**2 + &
2097	( omega_rot(inot) * cur_r - &
2098	vtheta(rseg) )**2 )
2099
2100	!
2101	!-- !-----------------------------------------------------------!
2102	!-- !-- Interpolation of chord as well as lift and drag --!
2103	!-- !-- coefficients from tabulated values --!
2104	!-- !-----------------------------------------------------------!
2105
2106	!
2107	!-- Interpolation of the chord_length from tabulated values to
2108	!-- the current radial position:
2109
2110	IF (cur_r == 0.0_wp) THEN
2111	chord(rseg) = 0.0_wp
2112	ELSE IF (cur_r >= lrd(size(crd))) THEN
2113	chord(rseg) = (crd(size(crd)) + ard(size(crd)-1)) / 2.0_wp
2114	ELSE
2115	chord(rseg) = ( crd(lct(1)) * &
2116	( ( lrd(lct(1)+1) - cur_r ) / &
2117	( lrd(lct(1)+1) - lrd(lct(1)) ) ) ) + &
2118	( crd(lct(1)+1) * &
2119	( ( cur_r-lrd(lct(1)) ) / &
2120	( lrd(lct(1)+1) - lrd(lct(1)) ) ) )
2121	ENDIF
2122
2123	!
2124	!-- Determine index of current angle of attack, needed for
2125	!-- finding the appropriate interpolated values of the lift and
2126	!-- drag coefficients (-180.0 degrees = 1, +180.0 degrees = 3601,
2127	!-- so one index every 0.1 degrees):
2128	iialpha = CEILING( ( alpha_attack(rseg) + 180.0_wp ) &
2129	* ( 1.0_wp / accu_cl_cd_tab ) ) + 1.0_wp
2130	!
2131	!-- Determine index of current radial position, needed for
2132	!-- finding the appropriate interpolated values of the lift and
2133	!-- drag coefficients (one index every 0.1 m):
2134	iir = CEILING( cur_r * 10.0_wp )
2135	!
2136	!-- Read in interpolated values of the lift and drag coefficients
2137	!-- for the current radial position and angle of attack:
2138	turb_cl(rseg) = turb_cl_tab(iialpha,iir)
2139	turb_cd(rseg) = turb_cd_tab(iialpha,iir)
2140
2141	!
2142	!-- Final transformation back from angles given in degree to
2143	!-- angles given in radian:
2144	alpha_attack(rseg) = alpha_attack(rseg) * &
2145	( (2.0_wp*pi) / 360.0_wp )
2146
2147	IF ( tl_cor ) THEN
2148
2149	!-- Tip loss correction following Schito
2150	!-- Schito applies the tip loss correction only to the lift force
2151	!-- Therefore, the tip loss correction is only applied to the lift
2152	!-- coefficient and not to the drag coefficient in our case
2153	!--
2154	tl_factor = ( 2.0 / pi ) * &
2155	ACOS( EXP( -1.0 * ( 3.0 * ( rr(inot) - cur_r ) / &
2156	( 2.0 * cur_r * abs( sin( phi_rel(rseg) ) ) ) ) ) )
2157
2158	turb_cl(rseg) = tl_factor * turb_cl(rseg)
2159
2160	ENDIF
2161	!
2162	!-- !-----------------------------------------------------!
2163	!-- !-- Calculation of the forces --!
2164	!-- !-----------------------------------------------------!
2165
2166	!
2167	!-- Calculate the pre_factor for the thrust and torque forces:
2168
2169	pre_factor = 0.5_wp * (vrel(rseg)*2) 3.0_wp * &
2170	chord(rseg) * delta_r(inot) / nsegs(ring,inot)
2171
2172	!
2173	!-- Calculate the thrust force (x-component of the total force)
2174	!-- for each ring segment:
2175	thrust_seg(rseg) = pre_factor * &
2176	( turb_cl(rseg) * COS(phi_rel(rseg)) + &
2177	turb_cd(rseg) * SIN(phi_rel(rseg)) )
2178
2179	!
2180	!-- Determination of the second of the additional forces acting
2181	!-- on the flow in the azimuthal direction: force vector as basis
2182	!-- for torque (torque itself would be the vector product of the
2183	!-- radius vector and the force vector):
2184	torque_seg = pre_factor * &
2185	( turb_cl(rseg) * SIN(phi_rel(rseg)) - &
2186	turb_cd(rseg) * COS(phi_rel(rseg)) )
2187	!
2188	!-- Decomposition of the force vector into two parts:
2189	!-- One acting along the y-direction and one acting along the
2190	!-- z-direction of the rotor coordinate system:
2191
2192	torque_seg_y(rseg) = -torque_seg * sin_rot
2193	torque_seg_z(rseg) = torque_seg * cos_rot
2194
2195	!
2196	!-- Add the segment thrust to the thrust of the whole rotor
2197	!$OMP CRITICAL
2198	thrust_rotor(inot) = thrust_rotor(inot) + &
2199	thrust_seg(rseg)
2200
2201
2202	torque_total(inot) = torque_total(inot) + (torque_seg * cur_r)
2203	!$OMP END CRITICAL
2204
2205	ENDDO !-- end of loop over ring segments
2206
2207	!
2208	!-- Restore the forces into arrays containing all the segments of
2209	!-- each ring:
2210	thrust_ring(ring,:) = thrust_seg(:)
2211	torque_ring_y(ring,:) = torque_seg_y(:)
2212	torque_ring_z(ring,:) = torque_seg_z(:)
2213
2214
2215	ENDDO !-- end of loop over rings
2216	!$OMP END PARALLEL
2217
2218
2219	CALL cpu_log( log_point_s(62), 'wtm_controller', 'start' )
2220
2221
2222	IF ( speed_control ) THEN
2223	!
2224	!-- Calculation of the current generator speed for rotor speed control
2225
2226	!
2227	!-- The acceleration of the rotor speed is calculated from
2228	!-- the force balance of the accelerating torque
2229	!-- and the torque of the rotating rotor and generator
2230	om_rate = ( torque_total(inot) * air_dens * gear_eff - &
2231	gear_ratio * torque_gen_old(inot) ) / &
2232	( inertia_rot + &
2233	gear_ratio * gear_ratio * inertia_gen ) * dt_3d
2234
2235	!
2236	!-- The generator speed is given by the product of gear gear_ratio
2237	!-- and rotor speed
2238	omega_gen(inot) = gear_ratio * ( omega_rot(inot) + om_rate )
2239
2240	ENDIF
2241
2242	IF ( pitch_control ) THEN
2243
2244	!
2245	!-- If the current generator speed is above rated, the pitch is not
2246	!-- saturated and the change from the last time step is within the
2247	!-- maximum pitch rate, then the pitch loop is repeated with a pitch
2248	!-- gain
2249	IF ( ( omega_gen(inot) > rated_genspeed ) .AND. &
2250	( pitch_add(inot) < 25.0_wp ) .AND. &
2251	( pitch_add(inot) < pitch_add_old(inot) + &
2252	pitch_rate * dt_3d ) ) THEN
2253	pitch_sw = .TRUE.
2254	!
2255	!-- Go back to beginning of pit_loop
2256	CYCLE pit_loop
2257	ENDIF
2258
2259	!
2260	!-- The current pitch is saved for the next time step
2261	pitch_add_old(inot) = pitch_add(inot)
2262	pitch_sw = .FALSE.
2263	ENDIF
2264	EXIT pit_loop
2265	ENDDO pit_loop ! Recursive pitch control loop
2266
2267
2268	!
2269	!-- Call the rotor speed controller
2270
2271	IF ( speed_control ) THEN
2272	!
2273	!-- Find processor at i_hub, j_hub
2274	IF ( ( nxl <= i_hub(inot) ) .AND. ( nxr >= i_hub(inot) ) ) &
2275	THEN
2276	IF ( ( nys <= j_hub(inot) ) .AND. ( nyn >= j_hub(inot) ) )&
2277	THEN
2278	CALL wtm_speed_control( inot )
2279	ENDIF
2280	ENDIF
2281
2282	ENDIF
2283
2284
2285	CALL cpu_log( log_point_s(62), 'wtm_controller', 'stop' )
2286
2287	CALL cpu_log( log_point_s(63), 'wtm_smearing', 'start' )
2288
2289
2290	!-- !-----------------------------------------------------------------!
2291	!-- !-- Regularization kernel --!
2292	!-- !-- Smearing of the forces and interpolation to cartesian grid --!
2293	!-- !-----------------------------------------------------------------!
2294	!
2295	!-- The aerodynamic blade forces need to be distributed smoothly on
2296	!-- several mesh points in order to avoid singular behaviour
2297	!
2298	!-- Summation over sum of weighted forces. The weighting factor
2299	!-- (calculated in user_init) includes information on the distance
2300	!-- between the center of the grid cell and the rotor segment under
2301	!-- consideration
2302	!
2303	!-- To save computing time, apply smearing only for the relevant part
2304	!-- of the model domain:
2305	!
2306	!--
2307	!-- Calculation of the boundaries:
2308	i_smear(inot) = CEILING( ( rr(inot) * ABS( roty(inot,1) ) + &
2309	eps_min ) / dx )
2310	j_smear(inot) = CEILING( ( rr(inot) * ABS( roty(inot,2) ) + &
2311	eps_min ) / dy )
2312
2313	!$OMP PARALLEL PRIVATE (i, j, k, ring, rseg, flag, dist_u_3d, dist_v_3d, dist_w_3d)
2314	!$OMP DO
2315	DO i = MAX( nxl, i_hub(inot) - i_smear(inot) ), &
2316	MIN( nxr, i_hub(inot) + i_smear(inot) )
2317	DO j = MAX( nys, j_hub(inot) - j_smear(inot) ), &
2318	MIN( nyn, j_hub(inot) + j_smear(inot) )
2319	! DO k = MAX( nzb_u_inner(j,i)+1, k_hub(inot) - k_smear(inot) ), &
2320	! k_hub(inot) + k_smear(inot)
2321	DO k = nzb+1, k_hub(inot) + k_smear(inot)
2322	DO ring = 1, nrings(inot)
2323	DO rseg = 1, nsegs(ring,inot)
2324	!
2325	!-- Predetermine flag to mask topography
2326	flag = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_0(k,j,i), 1 ) )
2327
2328	!
2329	!-- Determine the square of the distance between the
2330	!-- current grid point and each rotor area segment:
2331	dist_u_3d = ( i * dx - rbx(ring,rseg) )**2 + &
2332	( j * dy + 0.5_wp * dy - rby(ring,rseg) )**2 + &
2333	( k * dz(1) - 0.5_wp * dz(1) - rbz(ring,rseg) )**2
2334	dist_v_3d = ( i * dx + 0.5_wp * dx - rbx(ring,rseg) )**2 + &
2335	( j * dy - rby(ring,rseg) )**2 + &
2336	( k * dz(1) - 0.5_wp * dz(1) - rbz(ring,rseg) )**2
2337	dist_w_3d = ( i * dx + 0.5_wp * dx - rbx(ring,rseg) )**2 + &
2338	( j * dy + 0.5_wp * dy - rby(ring,rseg) )**2 + &
2339	( k * dz(1) - rbz(ring,rseg) )**2
2340
2341	!
2342	!-- 3D-smearing of the forces with a polynomial function
2343	!-- (much faster than the old Gaussian function), using
2344	!-- some parameters that have been calculated in user_init.
2345	!-- The function is only similar to Gaussian function for
2346	!-- squared distances <= eps_min2:
2347	IF ( dist_u_3d <= eps_min2 ) THEN
2348	thrust(k,j,i) = thrust(k,j,i) + &
2349	thrust_ring(ring,rseg) * &
2350	( ( pol_a * dist_u_3d - pol_b ) * &
2351	dist_u_3d + 1.0_wp ) * eps_factor *&
2352	flag
2353	ENDIF
2354	IF ( dist_v_3d <= eps_min2 ) THEN
2355	torque_y(k,j,i) = torque_y(k,j,i) + &
2356	torque_ring_y(ring,rseg) * &
2357	( ( pol_a * dist_v_3d - pol_b ) * &
2358	dist_v_3d + 1.0_wp ) * eps_factor * &
2359	flag
2360	ENDIF
2361	IF ( dist_w_3d <= eps_min2 ) THEN
2362	torque_z(k,j,i) = torque_z(k,j,i) + &
2363	torque_ring_z(ring,rseg) * &
2364	( ( pol_a * dist_w_3d - pol_b ) * &
2365	dist_w_3d + 1.0_wp ) * eps_factor * &
2366	flag
2367	ENDIF
2368
2369	ENDDO ! End of loop over rseg
2370	ENDDO ! End of loop over ring
2371
2372	!
2373	!-- Rotation of force components:
2374	rot_tend_x(k,j,i) = rot_tend_x(k,j,i) + ( &
2375	thrust(k,j,i)*rotx(inot,1) + &
2376	torque_y(k,j,i)*roty(inot,1) + &
2377	torque_z(k,j,i)*rotz(inot,1) &
2378	) * flag
2379
2380	rot_tend_y(k,j,i) = rot_tend_y(k,j,i) + ( &
2381	thrust(k,j,i)*rotx(inot,2) + &
2382	torque_y(k,j,i)*roty(inot,2) + &
2383	torque_z(k,j,i)*rotz(inot,2) &
2384	) * flag
2385
2386	rot_tend_z(k,j,i) = rot_tend_z(k,j,i) + ( &
2387	thrust(k,j,i)*rotx(inot,3) + &
2388	torque_y(k,j,i)*roty(inot,3) + &
2389	torque_z(k,j,i)*rotz(inot,3) &
2390	) * flag
2391
2392	ENDDO ! End of loop over k
2393	ENDDO ! End of loop over j
2394	ENDDO ! End of loop over i
2395	!$OMP END PARALLEL
2396
2397	CALL cpu_log( log_point_s(63), 'wtm_smearing', 'stop' )
2398
2399	ENDDO !-- end of loop over turbines
2400
2401
2402	IF ( yaw_control ) THEN
2403	!
2404	!-- Allocate arrays for yaw control at first call
2405	!-- Can't be allocated before dt_3d is set
2406	IF ( start_up ) THEN
2407	WDLON = NINT( 30.0_wp / dt_3d ) ! 30s running mean array
2408	ALLOCATE( wd30(1:nturbines,1:WDLON) )
2409	wd30 = 999.0_wp ! Set to dummy value
2410	ALLOCATE( wd30_l(1:WDLON) )
2411
2412	WDSHO = NINT( 2.0_wp / dt_3d ) ! 2s running mean array
2413	ALLOCATE( wd2(1:nturbines,1:WDSHO) )
2414	wd2 = 999.0_wp ! Set to dummy value
2415	ALLOCATE( wd2_l(1:WDSHO) )
2416	start_up = .FALSE.
2417	ENDIF
2418
2419	!
2420	!-- Calculate the inflow wind speed
2421	!--
2422	!-- Loop over number of turbines:
2423	DO inot = 1, nturbines
2424	!
2425	!-- Find processor at i_hub, j_hub
2426	IF ( ( nxl <= i_hub(inot) ) .AND. ( nxr >= i_hub(inot) ) ) &
2427	THEN
2428	IF ( ( nys <= j_hub(inot) ) .AND. ( nyn >= j_hub(inot) ) )&
2429	THEN
2430
2431	u_inflow_l(inot) = u(k_hub(inot),j_hub(inot),i_hub(inot))
2432
2433	wdir_l(inot) = -1.0_wp * ATAN2( &
2434	0.5_wp * ( v(k_hub(inot),j_hub(inot),i_hub(inot)+1) + &
2435	v(k_hub(inot),j_hub(inot),i_hub(inot)) ) , &
2436	0.5_wp * ( u(k_hub(inot),j_hub(inot)+1,i_hub(inot)) + &
2437	u(k_hub(inot),j_hub(inot),i_hub(inot)) ) )
2438
2439	CALL wtm_yawcontrol( inot )
2440
2441	phi_yaw_l(inot) = phi_yaw(inot)
2442
2443	ENDIF
2444	ENDIF
2445
2446	ENDDO !-- end of loop over turbines
2447
2448	!
2449	!-- Transfer of information to the other cpus
2450	#if defined( __parallel )
2451	CALL MPI_ALLREDUCE( u_inflow_l, u_inflow, nturbines, MPI_REAL, &
2452	MPI_SUM, comm2d, ierr )
2453	CALL MPI_ALLREDUCE( wdir_l, wdir, nturbines, MPI_REAL, MPI_SUM, &
2454	comm2d, ierr )
2455	CALL MPI_ALLREDUCE( phi_yaw_l, phi_yaw, nturbines, MPI_REAL, &
2456	MPI_SUM, comm2d, ierr )
2457	#else
2458	u_inflow = u_inflow_l
2459	wdir = wdir_l
2460	phi_yaw = phi_yaw_l
2461
2462
2463	#endif
2464	DO inot = 1, nturbines
2465	!
2466	!-- Update rotor orientation
2467	CALL wtm_rotate_rotor( inot )
2468
2469	ENDDO ! End of loop over turbines
2470
2471	ENDIF ! end of yaw control
2472
2473	IF ( speed_control ) THEN
2474	!
2475	!-- Transfer of information to the other cpus
2476	! CALL MPI_ALLREDUCE( omega_gen, omega_gen_old, nturbines, &
2477	! MPI_REAL,MPI_SUM, comm2d, ierr )
2478	#if defined( __parallel )
2479	CALL MPI_ALLREDUCE( torque_gen, torque_gen_old, nturbines, &
2480	MPI_REAL, MPI_SUM, comm2d, ierr )
2481	CALL MPI_ALLREDUCE( omega_rot_l, omega_rot, nturbines, &
2482	MPI_REAL, MPI_SUM, comm2d, ierr )
2483	CALL MPI_ALLREDUCE( omega_gen_f, omega_gen_f_old, nturbines, &
2484	MPI_REAL, MPI_SUM, comm2d, ierr )
2485	#else
2486	torque_gen_old = torque_gen
2487	omega_rot = omega_rot_l
2488	omega_gen_f_old = omega_gen_f
2489	#endif
2490
2491	ENDIF
2492
2493	DO inot = 1, nturbines
2494
2495	IF ( myid == 0 ) THEN
2496	IF ( openfile_turb_mod(400+inot)%opened ) THEN
2497	WRITE ( 400+inot, 106 ) simulated_time, omega_rot(inot), &
2498	omega_gen(inot), torque_gen_old(inot), &
2499	torque_total(inot), pitch_add(inot), &
2500	torque_gen_old(inot)omega_gen(inot)gen_eff, &
2501	torque_total(inot)omega_rot(inot)air_dens, &
2502	thrust_rotor(inot), &
2503	wdir(inot)*180.0_wp/pi, &
2504	(phi_yaw(inot))*180.0_wp/pi
2505
2506	ELSE
2507
2508	WRITE ( turbine_id,'(A2,I2.2)') '_T', inot
2509	OPEN ( 400+inot, FILE=( 'WTM_OUTPUT_DATA' // &
2510	TRIM( coupling_char ) // &
2511	turbine_id ), FORM='FORMATTED' )
2512	WRITE ( 400+inot, 105 ) inot
2513	WRITE ( 400+inot, 106 ) simulated_time, omega_rot(inot), &
2514	omega_gen(inot), torque_gen_old(inot), &
2515	torque_total(inot), pitch_add(inot), &
2516	torque_gen_old(inot)omega_gen(inot)gen_eff, &
2517	torque_total(inot)omega_rot(inot)air_dens, &
2518	thrust_rotor(inot), &
2519	wdir(inot)*180.0_wp/pi, &
2520	(phi_yaw(inot))*180.0_wp/pi
2521	ENDIF
2522	ENDIF
2523
2524	!-- Set open flag
2525	openfile_turb_mod(400+inot)%opened = .TRUE.
2526	ENDDO !-- end of loop over turbines
2527
2528	ENDIF
2529
2530	CALL cpu_log( log_point_s(61), 'wtm_forces', 'stop' )
2531
2532	!
2533	!-- Formats
2534	105 FORMAT ('Turbine control data for turbine ',I2,1X,':'/ &
2535	&'----------------------------------------'/ &
2536	&' Time RSpeed GSpeed ', &
2537	'GenTorque AeroTorque Pitch Power(Gen) Power(Rot) ', &
2538	'RotThrust WDirection YawOrient')
2539
2540	106 FORMAT (F9.3,2X,F7.3,2X,F7.2,2X,F9.1,3X,F9.1,1X,F6.2,2X,F10.1,2X, &
2541	F10.1,1X,F9.1,2X,F7.2,1X,F7.2)
2542
2543
2544	END SUBROUTINE wtm_forces
2545
2546
2547	!------------------------------------------------------------------------------!
2548	! Description:
2549	! ------------
2550	!> Yaw controller for the wind turbine model
2551	!------------------------------------------------------------------------------!
2552	SUBROUTINE wtm_yawcontrol( inot )
2553
2554	USE kinds
2555
2556	IMPLICIT NONE
2557
2558	INTEGER(iwp) :: inot
2559	INTEGER(iwp) :: i_wd_30
2560	REAL(wp) :: missal
2561
2562	i_wd_30 = 0_iwp
2563
2564	!
2565	!-- The yaw controller computes a 30s running mean of the wind direction.
2566	!-- If the difference between turbine alignment and wind direction exceeds
2567	!-- 5 degrees, the turbine is yawed. The mechanism stops as soon as the 2s-running
2568	!-- mean of the missalignment is smaller than 0.5 degrees.
2569	!-- Attention: If the timestep during the simulation changes significantly
2570	!-- the lengths of the running means change and it does not correspond to
2571	!-- 30s/2s anymore.
2572	!-- ! Needs to be modified for these situations !
2573	!-- For wind from the east, the averaging of the wind direction could cause
2574	!-- problems and the yaw controller is probably flawed. -> Routine for
2575	!-- averaging needs to be improved!
2576	!
2577	!-- Check if turbine is not yawing
2578	IF ( .NOT. doyaw(inot) ) THEN
2579	!
2580	!-- Write current wind direction into array
2581	wd30_l = wd30(inot,:)
2582	wd30_l = CSHIFT( wd30_l, SHIFT=-1 )
2583	wd30_l(1) = wdir(inot)
2584	!
2585	!-- Check if array is full ( no more dummies )
2586	IF ( .NOT. ANY( wd30_l == 999.) ) THEN
2587
2588	missal = SUM( wd30_l ) / SIZE( wd30_l ) - phi_yaw(inot)
2589	!
2590	!-- Check if turbine is missaligned by more than max_miss
2591	IF ( ABS( missal ) > max_miss ) THEN
2592	!
2593	!-- Check in which direction to yaw
2594	yawdir(inot) = SIGN( 1.0_wp, missal )
2595	!
2596	!-- Start yawing of turbine
2597	phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d
2598	doyaw(inot) = .TRUE.
2599	wd30_l = 999. ! fill with dummies again
2600	ENDIF
2601	ENDIF
2602
2603	wd30(inot,:) = wd30_l
2604
2605	!
2606	!-- If turbine is already yawing:
2607	!-- Initialize 2 s running mean and yaw until the missalignment is smaller
2608	!-- than min_miss
2609
2610	ELSE
2611	!
2612	!-- Initialize 2 s running mean
2613	wd2_l = wd2(inot,:)
2614	wd2_l = CSHIFT( wd2_l, SHIFT = -1 )
2615	wd2_l(1) = wdir(inot)
2616	!
2617	!-- Check if array is full ( no more dummies )
2618	IF ( .NOT. ANY( wd2_l == 999.0_wp ) ) THEN
2619	!
2620	!-- Calculate missalignment of turbine
2621	missal = SUM( wd2_l - phi_yaw(inot) ) / SIZE( wd2_l )
2622	!
2623	!-- Check if missalignment is still larger than 0.5 degree and if the
2624	!-- yaw direction is still right
2625	IF ( ( ABS( missal ) > min_miss ) .AND. &
2626	( yawdir(inot) == SIGN( 1.0_wp, missal ) ) ) THEN
2627	!
2628	!-- Continue yawing
2629	phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d
2630	ELSE
2631	!
2632	!-- Stop yawing
2633	doyaw(inot) = .FALSE.
2634	wd2_l = 999.0_wp ! fill with dummies again
2635	ENDIF
2636	ELSE
2637	!
2638	!-- Continue yawing
2639	phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d
2640	ENDIF
2641
2642	wd2(inot,:) = wd2_l
2643
2644	ENDIF
2645
2646	END SUBROUTINE wtm_yawcontrol
2647
2648
2649	!------------------------------------------------------------------------------!
2650	! Description:
2651	! ------------
2652	!> Initialization of the speed control
2653	!------------------------------------------------------------------------------!
2654	SUBROUTINE wtm_init_speed_control
2655
2656
2657	IMPLICIT NONE
2658
2659	!
2660	!-- If speed control is set, remaining variables and control_parameters for
2661	!-- the control algorithm are calculated
2662	!
2663	!-- Calculate slope constant for region 15
2664	slope15 = ( slope2 * min_reg2 * min_reg2 ) / ( min_reg2 - min_reg15 )
2665	!
2666	!-- Calculate upper limit of slipage region
2667	vs_sysp = rated_genspeed / 1.1_wp
2668	!
2669	!-- Calculate slope of slipage region
2670	slope25 = ( rated_power / rated_genspeed ) / &
2671	( rated_genspeed - vs_sysp )
2672	!
2673	!-- Calculate lower limit of slipage region
2674	min_reg25 = ( slope25 - SQRT( slope25 * ( slope25 - 4.0_wp * &
2675	slope2 * vs_sysp ) ) ) / &
2676	( 2.0_wp * slope2 )
2677	!
2678	!-- Frequency for the simple low pass filter
2679	Fcorner = 0.25_wp
2680	!
2681	!-- At the first timestep the torque is set to its maximum to prevent
2682	!-- an overspeeding of the rotor
2683	IF ( TRIM( initializing_actions ) /= 'read_restart_data' ) THEN
2684	torque_gen_old(:) = max_torque_gen
2685	ENDIF
2686
2687	END SUBROUTINE wtm_init_speed_control
2688
2689
2690	!------------------------------------------------------------------------------!
2691	! Description:
2692	! ------------
2693	!> Simple controller for the regulation of the rotor speed
2694	!------------------------------------------------------------------------------!
2695	SUBROUTINE wtm_speed_control( inot )
2696
2697
2698	IMPLICIT NONE
2699
2700	INTEGER(iwp) :: inot
2701
2702
2703
2704	!
2705	!-- The controller is based on the fortran script from Jonkman
2706	!-- et al. 2009 "Definition of a 5 MW Reference Wind Turbine for
2707	!-- offshore system developement"
2708
2709	!
2710	!-- The generator speed is filtered by a low pass filter
2711	!-- for the control of the generator torque
2712	lp_coeff = EXP( -2.0_wp * 3.14_wp * dt_3d * Fcorner )
2713	omega_gen_f(inot) = ( 1.0_wp - lp_coeff ) * omega_gen(inot) + lp_coeff *&
2714	omega_gen_f_old(inot)
2715
2716	IF ( omega_gen_f(inot) <= min_reg15 ) THEN
2717	!
2718	!-- Region 1: Generator torque is set to zero to accelerate the rotor:
2719	torque_gen(inot) = 0
2720
2721	ELSEIF ( omega_gen_f(inot) <= min_reg2 ) THEN
2722	!
2723	!-- Region 1.5: Generator torque is increasing linearly with rotor speed:
2724	torque_gen(inot) = slope15 * ( omega_gen_f(inot) - min_reg15 )
2725
2726	ELSEIF ( omega_gen_f(inot) <= min_reg25 ) THEN
2727	!
2728	!-- Region 2: Generator torque is increased by the square of the generator
2729	!-- speed to keep the TSR optimal:
2730	torque_gen(inot) = slope2 * omega_gen_f(inot) * omega_gen_f(inot)
2731
2732	ELSEIF ( omega_gen_f(inot) < rated_genspeed ) THEN
2733	!
2734	!-- Region 2.5: Slipage region between 2 and 3:
2735	torque_gen(inot) = slope25 * ( omega_gen_f(inot) - vs_sysp )
2736
2737	ELSE
2738	!
2739	!-- Region 3: Generator torque is antiproportional to the rotor speed to
2740	!-- keep the power constant:
2741	torque_gen(inot) = rated_power / omega_gen_f(inot)
2742
2743	ENDIF
2744	!
2745	!-- Calculate torque rate and confine with a max
2746	trq_rate = ( torque_gen(inot) - torque_gen_old(inot) ) / dt_3d
2747	trq_rate = MIN( MAX( trq_rate, -1.0_wp * max_trq_rate ), max_trq_rate )
2748	!
2749	!-- Calculate new gen torque and confine with max torque
2750	torque_gen(inot) = torque_gen_old(inot) + trq_rate * dt_3d
2751	torque_gen(inot) = MIN( torque_gen(inot), max_torque_gen )
2752	!
2753	!-- Overwrite values for next timestep
2754	omega_rot_l(inot) = omega_gen(inot) / gear_ratio
2755
2756
2757	END SUBROUTINE wtm_speed_control
2758
2759
2760	!------------------------------------------------------------------------------!
2761	! Description:
2762	! ------------
2763	!> Application of the additional forces generated by the wind turbine on the
2764	!> flow components (tendency terms)
2765	!> Call for all grid points
2766	!------------------------------------------------------------------------------!
2767	SUBROUTINE wtm_actions( location )
2768
2769
2770	CHARACTER (LEN=*) :: location !<
2771
2772	INTEGER(iwp) :: i !< running index
2773	INTEGER(iwp) :: j !< running index
2774	INTEGER(iwp) :: k !< running index
2775
2776
2777	SELECT CASE ( location )
2778
2779	CASE ( 'before_timestep' )
2780
2781	CALL wtm_forces
2782
2783	CASE ( 'u-tendency' )
2784	!
2785	!-- Apply the x-component of the force to the u-component of the flow:
2786	IF ( simulated_time >= time_turbine_on ) THEN
2787	DO i = nxlg, nxrg
2788	DO j = nysg, nyng
2789	DO k = nzb+1, MAXVAL(k_hub) + MAXVAL(k_smear)
2790	!
2791	!-- Calculate the thrust generated by the nacelle and the tower
2792	tend_nac_x = 0.5_wp * nac_cd_surf(k,j,i) * &
2793	SIGN( u(k,j,i)**2 , u(k,j,i) )
2794	tend_tow_x = 0.5_wp * tow_cd_surf(k,j,i) * &
2795	SIGN( u(k,j,i)**2 , u(k,j,i) )
2796
2797	tend(k,j,i) = tend(k,j,i) + ( - rot_tend_x(k,j,i) &
2798	- tend_nac_x - tend_tow_x ) &
2799	* MERGE( 1.0_wp, 0.0_wp, &
2800	BTEST( wall_flags_0(k,j,i), 1 ) )
2801	ENDDO
2802	ENDDO
2803	ENDDO
2804	ENDIF
2805
2806	CASE ( 'v-tendency' )
2807	!
2808	!-- Apply the y-component of the force to the v-component of the flow:
2809	IF ( simulated_time >= time_turbine_on ) THEN
2810	DO i = nxlg, nxrg
2811	DO j = nysg, nyng
2812	DO k = nzb+1, MAXVAL(k_hub) + MAXVAL(k_smear)
2813	tend_nac_y = 0.5_wp * nac_cd_surf(k,j,i) * &
2814	SIGN( v(k,j,i)**2 , v(k,j,i) )
2815	tend_tow_y = 0.5_wp * tow_cd_surf(k,j,i) * &
2816	SIGN( v(k,j,i)**2 , v(k,j,i) )
2817	tend(k,j,i) = tend(k,j,i) + ( - rot_tend_y(k,j,i) &
2818	- tend_nac_y - tend_tow_y ) &
2819	* MERGE( 1.0_wp, 0.0_wp, &
2820	BTEST( wall_flags_0(k,j,i), 2 ) )
2821	ENDDO
2822	ENDDO
2823	ENDDO
2824	ENDIF
2825
2826	CASE ( 'w-tendency' )
2827	!
2828	!-- Apply the z-component of the force to the w-component of the flow:
2829	IF ( simulated_time >= time_turbine_on ) THEN
2830	DO i = nxlg, nxrg
2831	DO j = nysg, nyng
2832	DO k = nzb+1, MAXVAL(k_hub) + MAXVAL(k_smear)
2833	tend(k,j,i) = tend(k,j,i) - rot_tend_z(k,j,i) &
2834	* MERGE( 1.0_wp, 0.0_wp, &
2835	BTEST( wall_flags_0(k,j,i), 3 ) )
2836	ENDDO
2837	ENDDO
2838	ENDDO
2839	ENDIF
2840
2841
2842	CASE DEFAULT
2843
2844	WRITE( message_string, * ) 'unknown prognostic variable: ', TRIM( location )
2845	CALL message( 'wtm_actions', 'PA04??', 1, 2, 0, 6, 0 )
2846
2847	END SELECT
2848
2849
2850	END SUBROUTINE wtm_actions
2851
2852
2853	!------------------------------------------------------------------------------!
2854	! Description:
2855	! ------------
2856	!> Application of the additional forces generated by the wind turbine on the
2857	!> flow components (tendency terms)
2858	!> Call for grid point i,j
2859	!------------------------------------------------------------------------------!
2860	SUBROUTINE wtm_actions_ij( i, j, location )
2861
2862
2863	CHARACTER (LEN=*) :: location !<
2864	INTEGER(iwp) :: i !< running index
2865	INTEGER(iwp) :: j !< running index
2866	INTEGER(iwp) :: k !< running index
2867
2868	SELECT CASE ( location )
2869
2870	CASE ( 'before_timestep' )
2871
2872	CALL wtm_forces
2873
2874	CASE ( 'u-tendency' )
2875	!
2876	!-- Apply the x-component of the force to the u-component of the flow:
2877	IF ( simulated_time >= time_turbine_on ) THEN
2878	DO k = nzb+1, MAXVAL(k_hub) + MAXVAL(k_smear)
2879	!
2880	!-- Calculate the thrust generated by the nacelle and the tower
2881	tend_nac_x = 0.5_wp * nac_cd_surf(k,j,i) * &
2882	SIGN( u(k,j,i)**2 , u(k,j,i) )
2883	tend_tow_x = 0.5_wp * tow_cd_surf(k,j,i) * &
2884	SIGN( u(k,j,i)**2 , u(k,j,i) )
2885	tend(k,j,i) = tend(k,j,i) + ( - rot_tend_x(k,j,i) &
2886	- tend_nac_x - tend_tow_x ) &
2887	* MERGE( 1.0_wp, 0.0_wp, &
2888	BTEST( wall_flags_0(k,j,i), 1 ) )
2889	ENDDO
2890	ENDIF
2891
2892	CASE ( 'v-tendency' )
2893	!
2894	!-- Apply the y-component of the force to the v-component of the flow:
2895	IF ( simulated_time >= time_turbine_on ) THEN
2896	DO k = nzb+1, MAXVAL(k_hub) + MAXVAL(k_smear)
2897	tend_nac_y = 0.5_wp * nac_cd_surf(k,j,i) * &
2898	SIGN( v(k,j,i)**2 , v(k,j,i) )
2899	tend_tow_y = 0.5_wp * tow_cd_surf(k,j,i) * &
2900	SIGN( v(k,j,i)**2 , v(k,j,i) )
2901	tend(k,j,i) = tend(k,j,i) + ( - rot_tend_y(k,j,i) &
2902	- tend_nac_y - tend_tow_y ) &
2903	* MERGE( 1.0_wp, 0.0_wp, &
2904	BTEST( wall_flags_0(k,j,i), 2 ) )
2905	ENDDO
2906	ENDIF
2907
2908	CASE ( 'w-tendency' )
2909	!
2910	!-- Apply the z-component of the force to the w-component of the flow:
2911	IF ( simulated_time >= time_turbine_on ) THEN
2912	DO k = nzb+1, MAXVAL(k_hub) + MAXVAL(k_smear)
2913	tend(k,j,i) = tend(k,j,i) - rot_tend_z(k,j,i) &
2914	* MERGE( 1.0_wp, 0.0_wp, &
2915	BTEST( wall_flags_0(k,j,i), 3 ) )
2916	ENDDO
2917	ENDIF
2918
2919
2920	CASE DEFAULT
2921
2922	WRITE( message_string, * ) 'unknown prognostic variable: ', TRIM( location )
2923	CALL message( 'wtm_actions', 'PA04??', 1, 2, 0, 6, 0 )
2924
2925	END SELECT
2926
2927
2928	END SUBROUTINE wtm_actions_ij
2929
2930	END MODULE wind_turbine_model_mod

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