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source: palm/trunk/SOURCE/wind_turbine_model_mod.f90 @ 3461

Last change on this file since 3461 was 3274, checked in by knoop, 6 years ago
Modularization of all bulk cloud physics code components
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File size: 120.3 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 2009-2018 Carl von Ossietzky Universitaet Oldenburg
18	! Copyright 1997-2018 Leibniz Universitaet Hannover
19	!------------------------------------------------------------------------------!
20	!
21	! Current revisions:
22	! -----------------
23	!
24	!
25	! Former revisions:
26	! -----------------
27	! $Id: wind_turbine_model_mod.f90 3274 2018-09-24 15:42:55Z knoop $
28	! Modularization of all bulk cloud physics code components
29	!
30	! 3248 2018-09-14 09:42:06Z sward
31	! Minor formating changes
32	!
33	! 3246 2018-09-13 15:14:50Z sward
34	! Added error handling for input namelist via parin_fail_message
35	!
36	! 3241 2018-09-12 15:02:00Z raasch
37	! unused variables removed
38	!
39	! 3182 2018-07-27 13:36:03Z suehring
40	! Check for vertical stretching has been revised.
41	!
42	! 3139 2018-07-17 11:30:10Z Giersch
43	! Bugfix in calculation of alpha_attack
44	!
45	! 3069 2018-06-15 07:56:09Z witha
46	! Initialization of some arrays added
47	!
48	! 3066 2018-06-12 08:55:55Z Giersch
49	! Error message revised
50	!
51	! 3065 2018-06-12 07:03:02Z Giersch
52	! dz was replaced by dz(1), error message concerning grid stretching has been
53	! introduced
54	!
55	! 3049 2018-05-29 13:52:36Z Giersch
56	! Error messages revised
57	!
58	! 2932 2018-03-26 09:39:22Z Giersch
59	! renamed wind_turbine_par to wind_turbine_parameters
60	!
61	! 2894 2018-03-15 09:17:58Z Giersch
62	! variable named found has been introduced for checking if restart data was
63	! found, reading of restart strings has been moved completely to
64	! read_restart_data_mod, wind_turbine_prerun flag has been removed, redundant
65	! skipping function has been removed, wtm_read/write_restart_data have been
66	! renamed to wtm_r/wrd_global, wtm_rrd_global is called in
67	! read_restart_data_mod now, marker * end wtm * was removed, strings and
68	! their respective lengths are written out and read now in case of restart
69	! runs to get rid of prescribed character lengths, CASE DEFAULT was added if
70	! restart data is read
71	!
72	! 2885 2018-03-14 11:02:46Z Giersch
73	! Bugfix in interpolation of lift and drag coefficients on fine grid of radius
74	! segments and angles of attack, speed-up of the initialization of the wind
75	! turbine model
76	!
77	! 2792 2018-02-07 06:45:29Z Giersch
78	! omega_rot_l has to be calculated after determining the indices for the hub in
79	! case of restart runs
80	!
81	! 2776 2018-01-31 10:44:42Z Giersch
82	! wind_turbine_prerun flag is used to define if module
83	! related parameters were outputted as restart data
84	!
85	! 2718 2018-01-02 08:49:38Z maronga
86	! Corrected "Former revisions" section
87	!
88	! 2696 2017-12-14 17:12:51Z kanani
89	! Change in file header (GPL part)
90	!
91	! 2669 2017-12-06 16:03:27Z raasch
92	! filename of turbine output changed to WTM_OUTPUT_DATA. File extension now
93	! includes the nest domain number. Turbine extension changed to "_T##"
94	!
95	! 2576 2017-10-24 13:49:46Z Giersch
96	! Definition of a new function called wtm_skip_global to skip module
97	! parameters during reading restart data
98	!
99	! 2563 2017-10-19 15:36:10Z Giersch
100	! Restart runs with wind turbine model are possible now. For this purpose, two
101	! new subroutines wtm_write_restart_data and wtm_read_restart_data had to be
102	! defined
103	!
104	! 2553 2017-10-18 08:03:45Z Giersch
105	! Bugfix of vertical loop in wtm_tendencies to account for different turbine
106	! heights, bugfix of the interpolation of the u-component concerning the
107	! vertical index and further small adjustments of the programming style
108	!
109	! 2410 2017-09-06 08:16:30Z Giersch
110	! Revise error message PA0462
111	!
112	! 2349 2017-08-10 15:44:04Z Giersch
113	! Add parameter pitch_rate to namelist and revise/add error messages
114	!
115	! 2343 2017-08-08 11:28:43Z Giersch
116	! Unit correction in Doxygen comments
117	!
118	! 2323 2017-07-26 12:57:38Z Giersch
119	! Change unit number of file WTM_DATA from 201 to 90
120	!
121	! 2322 2017-07-26 08:30:28Z Giersch
122	! Bugfix of error message and assign error numbers
123	!
124	! 2257 2017-06-07 14:07:05Z witha
125	! Bugfix: turb_cl_tab and turb_cd_tab were set to zero before being allocated
126	!
127	! 2233 2017-05-30 18:08:54Z suehring
128	!
129	! 2232 2017-05-30 17:47:52Z suehring
130	! Adjustments to new topography concept
131	!
132	! 2152 2017-02-17 13:27:24Z lvollmer
133	! Bugfix in subroutine wtm_read_blade_tables
134	! Addition of a tip loss model
135	!
136	! 2015 2016-09-28 08:45:18Z lvollmer
137	! Bugfix of pitch control
138	!
139	! 2000 2016-08-20 18:09:15Z knoop
140	! Forced header and separation lines into 80 columns
141	!
142	! 1929 2016-06-09 16:25:25Z suehring
143	! Bugfix: added preprocessor directives for parallel and serial mode
144	!
145	! 1914 2016-05-26 14:44:07Z witha
146	! Initial revision
147	!
148	!
149	! Description:
150	! ------------
151	!> This module calculates the effect of wind turbines on the flow fields. The
152	!> initial version contains only the advanced actuator disk with rotation method
153	!> (ADM-R).
154	!> The wind turbines include the tower effect, can be yawed and tilted.
155	!> The wind turbine model includes controllers for rotational speed, pitch and
156	!> yaw.
157	!> Currently some specifications of the NREL 5 MW reference turbine
158	!> are hardcoded whereas most input data comes from separate files (currently
159	!> external, planned to be included as namelist which will be read in
160	!> automatically).
161	!>
162	!> @todo Replace dz(1) appropriatly to account for grid stretching
163	!> @todo Revise code according to PALM Coding Standard
164	!> @todo Implement ADM and ALM turbine models
165	!> @todo Generate header information
166	!> @todo Implement further parameter checks and error messages
167	!> @todo Revise and add code documentation
168	!> @todo Output turbine parameters as timeseries
169	!> @todo Include additional output variables
170	!> @todo Revise smearing the forces for turbines in yaw
171	!> @todo Revise nacelle and tower parameterization
172	!> @todo Allow different turbine types in one simulation
173	!
174	!------------------------------------------------------------------------------!
175	MODULE wind_turbine_model_mod
176
177	USE arrays_3d, &
178	ONLY: tend, u, v, w, zu, zw
179
180	USE basic_constants_and_equations_mod, &
181	ONLY: pi
182
183	USE control_parameters, &
184	ONLY: coupling_char, dt_3d, dz, message_string, simulated_time, &
185	wind_turbine, initializing_actions
186
187	USE cpulog, &
188	ONLY: cpu_log, log_point_s
189
190	USE grid_variables, &
191	ONLY: ddx, dx, ddy, dy
192
193	USE indices, &
194	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nz, &
195	nzb, nzt, wall_flags_0
196
197	USE kinds
198
199	USE pegrid
200
201
202	IMPLICIT NONE
203
204	PRIVATE
205
206	!
207	!-- Variables specified in the namelist wind_turbine_par
208
209	INTEGER(iwp) :: nairfoils = 8 !< number of airfoils of the used turbine model (for ADM-R and ALM)
210	INTEGER(iwp) :: nturbines = 1 !< number of turbines
211
212	LOGICAL :: pitch_control = .FALSE. !< switch for use of pitch controller
213	LOGICAL :: speed_control = .FALSE. !< switch for use of speed controller
214	LOGICAL :: yaw_control = .FALSE. !< switch for use of yaw controller
215	LOGICAL :: tl_cor = .FALSE. !< switch for use of tip loss correct.
216
217	REAL(wp) :: segment_length = 1.0_wp !< length of the segments, the rotor area is divided into
218	!< (in tangential direction, as factor of MIN(dx,dy,dz))
219	REAL(wp) :: segment_width = 0.5_wp !< width of the segments, the rotor area is divided into
220	!< (in radial direction, as factor of MIN(dx,dy,dz))
221	REAL(wp) :: time_turbine_on = 0.0_wp !< time at which turbines are started
222	REAL(wp) :: tilt = 0.0_wp !< vertical tilt of the rotor [degree] ( positive = backwards )
223
224	REAL(wp), DIMENSION(1:100) :: dtow = 0.0_wp !< tower diameter [m]
225	REAL(wp), DIMENSION(1:100) :: omega_rot = 0.9_wp !< inital or constant rotor speed [rad/s]
226	REAL(wp), DIMENSION(1:100) :: phi_yaw = 0.0_wp !< yaw angle [degree] ( clockwise, 0 = facing west )
227	REAL(wp), DIMENSION(1:100) :: pitch_add = 0.0_wp !< constant pitch angle
228	REAL(wp), DIMENSION(1:100) :: rcx = 9999999.9_wp !< position of hub in x-direction
229	REAL(wp), DIMENSION(1:100) :: rcy = 9999999.9_wp !< position of hub in y-direction
230	REAL(wp), DIMENSION(1:100) :: rcz = 9999999.9_wp !< position of hub in z-direction
231	REAL(wp), DIMENSION(1:100) :: rnac = 0.0_wp !< nacelle diameter [m]
232	REAL(wp), DIMENSION(1:100) :: rr = 63.0_wp !< rotor radius [m]
233	REAL(wp), DIMENSION(1:100) :: turb_cd_nacelle = 0.85_wp !< drag coefficient for nacelle
234	REAL(wp), DIMENSION(1:100) :: turb_cd_tower = 1.2_wp !< drag coefficient for tower
235
236	!
237	!-- Variables specified in the namelist for speed controller
238	!-- Default values are from the NREL 5MW research turbine (Jonkman, 2008)
239
240	REAL(wp) :: rated_power = 5296610.0_wp !< rated turbine power [W]
241	REAL(wp) :: gear_ratio = 97.0_wp !< Gear ratio from rotor to generator
242	REAL(wp) :: inertia_rot = 34784179.0_wp !< Inertia of the rotor [kg*m2]
243	REAL(wp) :: inertia_gen = 534.116_wp !< Inertia of the generator [kg*m2]
244	REAL(wp) :: gen_eff = 0.944_wp !< Electric efficiency of the generator
245	REAL(wp) :: gear_eff = 1.0_wp !< Loss between rotor and generator
246	REAL(wp) :: air_dens = 1.225_wp !< Air density to convert to W [kg/m3]
247	REAL(wp) :: rated_genspeed = 121.6805_wp !< Rated generator speed [rad/s]
248	REAL(wp) :: max_torque_gen = 47402.91_wp !< Maximum of the generator torque [Nm]
249	REAL(wp) :: slope2 = 2.332287_wp !< Slope constant for region 2
250	REAL(wp) :: min_reg2 = 91.21091_wp !< Lower generator speed boundary of region 2 [rad/s]
251	REAL(wp) :: min_reg15 = 70.16224_wp !< Lower generator speed boundary of region 1.5 [rad/s]
252	REAL(wp) :: max_trq_rate = 15000.0_wp !< Max generator torque increase [Nm/s]
253	REAL(wp) :: pitch_rate = 8.0_wp !< Max pitch rate [degree/s]
254
255
256	!
257	!-- Variables specified in the namelist for yaw control
258
259	REAL(wp) :: yaw_speed = 0.005236_wp !< speed of the yaw actuator [rad/s]
260	REAL(wp) :: max_miss = 0.08726_wp !< maximum tolerated yaw missalignment [rad]
261	REAL(wp) :: min_miss = 0.008726_wp !< minimum yaw missalignment for which the actuator stops [rad]
262
263	!
264	!-- Set flag for output files TURBINE_PARAMETERS
265	TYPE file_status
266	LOGICAL :: opened, opened_before
267	END TYPE file_status
268
269	TYPE(file_status), DIMENSION(500) :: openfile_turb_mod = &
270	file_status(.FALSE.,.FALSE.)
271
272	!
273	!-- Variables for initialization of the turbine model
274
275	INTEGER(iwp) :: inot !< turbine loop index (turbine id)
276	INTEGER(iwp) :: nsegs_max !< maximum number of segments (all turbines, required for allocation of arrays)
277	INTEGER(iwp) :: nrings_max !< maximum number of rings (all turbines, required for allocation of arrays)
278	INTEGER(iwp) :: ring !< ring loop index (ring number)
279	INTEGER(iwp) :: upper_end !<
280
281	INTEGER(iwp), DIMENSION(1) :: lct !<
282
283	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: i_hub !< index belonging to x-position of the turbine
284	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: i_smear !< index defining the area for the smearing of the forces (x-direction)
285	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: j_hub !< index belonging to y-position of the turbine
286	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: j_smear !< index defining the area for the smearing of the forces (y-direction)
287	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: k_hub !< index belonging to hub height
288	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: k_smear !< index defining the area for the smearing of the forces (z-direction)
289	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nrings !< number of rings per turbine
290	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nsegs_total !< total number of segments per turbine
291
292	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: nsegs !< number of segments per ring and turbine
293
294	!
295	!- parameters for the smearing from the rotor to the cartesian grid
296	REAL(wp) :: pol_a !< parameter for the polynomial smearing fct
297	REAL(wp) :: pol_b !< parameter for the polynomial smearing fct
298	REAL(wp) :: delta_t_factor !<
299	REAL(wp) :: eps_factor !<
300	REAL(wp) :: eps_min !<
301	REAL(wp) :: eps_min2 !<
302	REAL(wp) :: sqrt_arg !<
303
304	!
305	!-- Variables for the calculation of lift and drag coefficients
306	REAL(wp), DIMENSION(:), ALLOCATABLE :: ard !<
307	REAL(wp), DIMENSION(:), ALLOCATABLE :: crd !<
308	REAL(wp), DIMENSION(:), ALLOCATABLE :: delta_r !< radial segment length
309	REAL(wp), DIMENSION(:), ALLOCATABLE :: lrd !<
310
311	REAL(wp) :: accu_cl_cd_tab = 0.1_wp !< Accuracy of the interpolation of
312	!< the lift and drag coeff [deg]
313
314	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cd_tab !< table of the blade drag coefficient
315	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cl_tab !< table of the blade lift coefficient
316
317	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: nac_cd_surf !< 3d field of the tower drag coefficient
318	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: tow_cd_surf !< 3d field of the nacelle drag coefficient
319
320	!
321	!-- Variables for the calculation of the forces
322
323	REAL(wp) :: cur_r !<
324	REAL(wp) :: phi_rotor !<
325	REAL(wp) :: pre_factor !<
326	REAL(wp) :: torque_seg !<
327	REAL(wp) :: u_int_l !<
328	REAL(wp) :: u_int_u !<
329	REAL(wp) :: u_rot !<
330	REAL(wp) :: v_int_l !<
331	REAL(wp) :: v_int_u !<
332	REAL(wp) :: w_int_l !<
333	REAL(wp) :: w_int_u !<
334	!
335	!- Tendencies from the nacelle and tower thrust
336	REAL(wp) :: tend_nac_x = 0.0_wp !<
337	REAL(wp) :: tend_tow_x = 0.0_wp !<
338	REAL(wp) :: tend_nac_y = 0.0_wp !<
339	REAL(wp) :: tend_tow_y = 0.0_wp !<
340
341	REAL(wp), DIMENSION(:), ALLOCATABLE :: alpha_attack !<
342	REAL(wp), DIMENSION(:), ALLOCATABLE :: chord !<
343	REAL(wp), DIMENSION(:), ALLOCATABLE :: phi_rel !<
344	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_total !<
345	REAL(wp), DIMENSION(:), ALLOCATABLE :: thrust_rotor !<
346	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl !<
347	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd !<
348	REAL(wp), DIMENSION(:), ALLOCATABLE :: vrel !<
349	REAL(wp), DIMENSION(:), ALLOCATABLE :: vtheta !<
350
351	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: rbx, rby, rbz !< coordinates of the blade elements
352	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: rotx, roty, rotz !< normal vectors to the rotor coordinates
353
354	!
355	!- Fields for the interpolation of velocities on the rotor grid
356	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: u_int !<
357	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: u_int_1_l !<
358	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: v_int !<
359	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: v_int_1_l !<
360	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: w_int !<
361	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: w_int_1_l !<
362
363	!
364	!- rotor tendencies on the segments
365	REAL(wp), DIMENSION(:), ALLOCATABLE :: thrust_seg !<
366	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_seg_y !<
367	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_seg_z !<
368
369	!
370	!- rotor tendencies on the rings
371	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: thrust_ring !<
372	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: torque_ring_y !<
373	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: torque_ring_z !<
374
375	!
376	!- rotor tendencies on rotor grids for all turbines
377	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: thrust !<
378	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: torque_y !<
379	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: torque_z !<
380
381	!
382	!- rotor tendencies on coordinate grid
383	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_x !<
384	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_y !<
385	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_z !<
386	!
387	!- variables for the rotation of the rotor coordinates
388	REAL(wp), DIMENSION(1:100,1:3,1:3) :: rot_coord_trans !< matrix for rotation of rotor coordinates
389
390	REAL(wp), DIMENSION(1:3) :: rot_eigen_rad !<
391	REAL(wp), DIMENSION(1:3) :: rot_eigen_azi !<
392	REAL(wp), DIMENSION(1:3) :: rot_eigen_nor !<
393	REAL(wp), DIMENSION(1:3) :: re !<
394	REAL(wp), DIMENSION(1:3) :: rea !<
395	REAL(wp), DIMENSION(1:3) :: ren !<
396	REAL(wp), DIMENSION(1:3) :: rote !<
397	REAL(wp), DIMENSION(1:3) :: rota !<
398	REAL(wp), DIMENSION(1:3) :: rotn !<
399
400	!
401	!-- Fixed variables for the speed controller
402
403	LOGICAL :: start_up = .TRUE. !<
404
405	REAL(wp) :: Fcorner !< corner freq for the controller low pass filter
406	REAL(wp) :: min_reg25 !< min region 2.5
407	REAL(wp) :: om_rate !< rotor speed change
408	REAL(wp) :: slope15 !< slope in region 1.5
409	REAL(wp) :: slope25 !< slope in region 2.5
410	REAL(wp) :: trq_rate !< torque change
411	REAL(wp) :: vs_sysp !<
412	REAL(wp) :: lp_coeff !< coeff for the controller low pass filter
413
414	REAL(wp), DIMENSION(100) :: omega_rot_l = 0.0_wp !< local rot speed [rad/s]
415
416	!
417	!-- Fixed variables for the yaw controller
418
419	REAL(wp), DIMENSION(:) , ALLOCATABLE :: yawdir !< direction to yaw
420	REAL(wp), DIMENSION(:) , ALLOCATABLE :: phi_yaw_l !< local (cpu) yaw angle
421	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wd30_l !< local (cpu) long running avg of the wd
422	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wd2_l !< local (cpu) short running avg of the wd
423	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wdir !< wind direction at hub
424	REAL(wp), DIMENSION(:) , ALLOCATABLE :: u_inflow !< wind speed at hub
425	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wdir_l !<
426	REAL(wp), DIMENSION(:) , ALLOCATABLE :: u_inflow_l !<
427	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: wd30 !<
428	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: wd2 !<
429	LOGICAL, DIMENSION(1:100) :: doyaw = .FALSE. !<
430	INTEGER(iwp) :: WDLON !<
431	INTEGER(iwp) :: WDSHO !<
432
433	!
434	!-- Variables that have to be saved in the binary file for restarts
435	REAL(wp), DIMENSION(1:100) :: pitch_add_old = 0.0_wp !< old constant pitch angle
436	REAL(wp), DIMENSION(1:100) :: omega_gen = 0.0_wp !< curr. generator speed
437	REAL(wp), DIMENSION(1:100) :: omega_gen_f = 0.0_wp !< filtered generator speed
438	REAL(wp), DIMENSION(1:100) :: omega_gen_old = 0.0_wp !< last generator speed
439	REAL(wp), DIMENSION(1:100) :: omega_gen_f_old = 0.0_wp !< last filtered generator speed
440	REAL(wp), DIMENSION(1:100) :: torque_gen = 0.0_wp !< generator torque
441	REAL(wp), DIMENSION(1:100) :: torque_gen_old = 0.0_wp !< last generator torque
442
443
444	SAVE
445
446
447	INTERFACE wtm_parin
448	MODULE PROCEDURE wtm_parin
449	END INTERFACE wtm_parin
450
451	INTERFACE wtm_wrd_global
452	MODULE PROCEDURE wtm_wrd_global
453	END INTERFACE wtm_wrd_global
454
455	INTERFACE wtm_rrd_global
456	MODULE PROCEDURE wtm_rrd_global
457	END INTERFACE wtm_rrd_global
458
459	INTERFACE wtm_check_parameters
460	MODULE PROCEDURE wtm_check_parameters
461	END INTERFACE wtm_check_parameters
462
463	INTERFACE wtm_init_arrays
464	MODULE PROCEDURE wtm_init_arrays
465	END INTERFACE wtm_init_arrays
466
467	INTERFACE wtm_init
468	MODULE PROCEDURE wtm_init
469	END INTERFACE wtm_init
470
471	INTERFACE wtm_read_blade_tables
472	MODULE PROCEDURE wtm_read_blade_tables
473	END INTERFACE wtm_read_blade_tables
474
475	INTERFACE wtm_forces
476	MODULE PROCEDURE wtm_forces
477	END INTERFACE wtm_forces
478
479	INTERFACE wtm_yawcontrol
480	MODULE PROCEDURE wtm_yawcontrol
481	END INTERFACE wtm_yawcontrol
482
483	INTERFACE wtm_rotate_rotor
484	MODULE PROCEDURE wtm_rotate_rotor
485	END INTERFACE wtm_rotate_rotor
486
487	INTERFACE wtm_speed_control
488	MODULE PROCEDURE wtm_init_speed_control
489	MODULE PROCEDURE wtm_speed_control
490	END INTERFACE wtm_speed_control
491
492	INTERFACE wtm_tendencies
493	MODULE PROCEDURE wtm_tendencies
494	MODULE PROCEDURE wtm_tendencies_ij
495	END INTERFACE wtm_tendencies
496
497
498	PUBLIC wtm_check_parameters, wtm_forces, wtm_init, wtm_init_arrays, &
499	wtm_parin, wtm_wrd_global, wtm_rrd_global, wtm_tendencies
500
501
502	CONTAINS
503
504
505	!------------------------------------------------------------------------------!
506	! Description:
507	! ------------
508	!> Parin for &wind_turbine_par for wind turbine model
509	!------------------------------------------------------------------------------!
510	SUBROUTINE wtm_parin
511
512
513	IMPLICIT NONE
514
515	INTEGER(iwp) :: ierrn !<
516
517	CHARACTER (LEN=80) :: line !< dummy string that contains the current line of the parameter file
518
519	NAMELIST /wind_turbine_par/ air_dens, dtow, gear_eff, gear_ratio, &
520	gen_eff, inertia_gen, inertia_rot, max_miss, &
521	max_torque_gen, max_trq_rate, min_miss, &
522	min_reg15, min_reg2, nairfoils, nturbines, &
523	omega_rot, phi_yaw, pitch_add, pitch_control,&
524	rated_genspeed, rated_power, rcx, rcy, rcz, &
525	rnac, rr, segment_length, segment_width, &
526	slope2, speed_control, tilt, time_turbine_on,&
527	turb_cd_nacelle, turb_cd_tower, pitch_rate, &
528	yaw_control, yaw_speed, tl_cor
529
530	NAMELIST /wind_turbine_parameters/ &
531	air_dens, dtow, gear_eff, gear_ratio, &
532	gen_eff, inertia_gen, inertia_rot, max_miss, &
533	max_torque_gen, max_trq_rate, min_miss, &
534	min_reg15, min_reg2, nairfoils, nturbines, &
535	omega_rot, phi_yaw, pitch_add, pitch_control,&
536	rated_genspeed, rated_power, rcx, rcy, rcz, &
537	rnac, rr, segment_length, segment_width, &
538	slope2, speed_control, tilt, time_turbine_on,&
539	turb_cd_nacelle, turb_cd_tower, pitch_rate, &
540	yaw_control, yaw_speed, tl_cor
541	!
542	!-- Try to find wind turbine model package
543	REWIND ( 11 )
544	line = ' '
545	DO WHILE ( INDEX( line, '&wind_turbine_parameters' ) == 0 )
546	READ ( 11, '(A)', END=12 ) line
547	ENDDO
548	BACKSPACE ( 11 )
549
550	!
551	!-- Read user-defined namelist
552	READ ( 11, wind_turbine_parameters, ERR = 10 )
553	!
554	!-- Set flag that indicates that the wind turbine model is switched on
555	wind_turbine = .TRUE.
556
557	GOTO 14
558
559	10 BACKSPACE( 11 )
560	READ( 11 , '(A)') line
561	CALL parin_fail_message( 'wind_turbine_parameters', line )
562
563	!
564	!-- Try to find wind turbine model package
565	12 REWIND ( 11 )
566	line = ' '
567	DO WHILE ( INDEX( line, '&wind_turbine_par' ) == 0 )
568	READ ( 11, '(A)', END=14 ) line
569	ENDDO
570	BACKSPACE ( 11 )
571
572	!
573	!-- Read user-defined namelist
574	READ ( 11, wind_turbine_par, ERR = 13, END = 14 )
575
576	message_string = 'namelist wind_tubrine_par is deprecated and will ' // &
577	'be removed in near future. &Please use namelist ' // &
578	'wind_turbine_parameters instead'
579	CALL message( 'wtm_parin', 'PA0487', 0, 1, 0, 6, 0 )
580
581	!
582	!-- Set flag that indicates that the wind turbine model is switched on
583	wind_turbine = .TRUE.
584
585	GOTO 14
586
587	13 BACKSPACE( 11 )
588	READ( 11 , '(A)') line
589	CALL parin_fail_message( 'wind_turbine_par', line )
590
591	14 CONTINUE ! TBD Change from continue, mit ierrn machen
592
593
594	END SUBROUTINE wtm_parin
595
596
597	!------------------------------------------------------------------------------!
598	! Description:
599	! ------------
600	!> This routine writes the respective restart data.
601	!------------------------------------------------------------------------------!
602	SUBROUTINE wtm_wrd_global
603
604
605	IMPLICIT NONE
606
607
608	CALL wrd_write_string( 'omega_gen' )
609	WRITE ( 14 ) omega_gen
610
611	CALL wrd_write_string( 'omega_gen_f' )
612	WRITE ( 14 ) omega_gen_f
613
614	CALL wrd_write_string( 'omega_gen_f_old' )
615	WRITE ( 14 ) omega_gen_f_old
616
617	CALL wrd_write_string( 'omega_gen_old' )
618	WRITE ( 14 ) omega_gen_old
619
620	CALL wrd_write_string( 'omega_rot' )
621	WRITE ( 14 ) omega_rot
622
623	CALL wrd_write_string( 'phi_yaw' )
624	WRITE ( 14 ) phi_yaw
625
626	CALL wrd_write_string( 'pitch_add' )
627	WRITE ( 14 ) pitch_add
628
629	CALL wrd_write_string( 'pitch_add_old' )
630	WRITE ( 14 ) pitch_add_old
631
632	CALL wrd_write_string( 'torque_gen' )
633	WRITE ( 14 ) torque_gen
634
635	CALL wrd_write_string( 'torque_gen_old' )
636	WRITE ( 14 ) torque_gen_old
637
638
639	END SUBROUTINE wtm_wrd_global
640
641
642	!------------------------------------------------------------------------------!
643	! Description:
644	! ------------
645	!> This routine reads the respective restart data.
646	!------------------------------------------------------------------------------!
647	SUBROUTINE wtm_rrd_global( found )
648
649
650	USE control_parameters, &
651	ONLY: length, restart_string
652
653
654	IMPLICIT NONE
655
656	LOGICAL, INTENT(OUT) :: found
657
658
659	found = .TRUE.
660
661
662	SELECT CASE ( restart_string(1:length) )
663
664	CASE ( 'omega_gen' )
665	READ ( 13 ) omega_gen
666	CASE ( 'omega_gen_f' )
667	READ ( 13 ) omega_gen_f
668	CASE ( 'omega_gen_f_old' )
669	READ ( 13 ) omega_gen_f_old
670	CASE ( 'omega_gen_old' )
671	READ ( 13 ) omega_gen_old
672	CASE ( 'omega_rot' )
673	READ ( 13 ) omega_rot
674	CASE ( 'phi_yaw' )
675	READ ( 13 ) phi_yaw
676	CASE ( 'pitch_add' )
677	READ ( 13 ) pitch_add
678	CASE ( 'pitch_add_old' )
679	READ ( 13 ) pitch_add_old
680	CASE ( 'torque_gen' )
681	READ ( 13 ) torque_gen
682	CASE ( 'torque_gen_old' )
683	READ ( 13 ) torque_gen_old
684
685	CASE DEFAULT
686
687	found = .FALSE.
688
689	END SELECT
690
691
692	END SUBROUTINE wtm_rrd_global
693
694
695	!------------------------------------------------------------------------------!
696	! Description:
697	! ------------
698	!> Check namelist parameter
699	!------------------------------------------------------------------------------!
700	SUBROUTINE wtm_check_parameters
701
702
703	IMPLICIT NONE
704
705	IF ( ( .NOT.speed_control ) .AND. pitch_control ) THEN
706	message_string = 'pitch_control = .TRUE. requires '// &
707	'speed_control = .TRUE.'
708	CALL message( 'wtm_check_parameters', 'PA0461', 1, 2, 0, 6, 0 )
709	ENDIF
710
711	IF ( ANY( omega_rot(1:nturbines) < 0.0 ) ) THEN
712	message_string = 'omega_rot < 0.0, Please set omega_rot to ' // &
713	'a value equal or larger than zero'
714	CALL message( 'wtm_check_parameters', 'PA0462', 1, 2, 0, 6, 0 )
715	ENDIF
716
717
718	IF ( ANY( rcx(1:nturbines) == 9999999.9_wp ) .OR. &
719	ANY( rcy(1:nturbines) == 9999999.9_wp ) .OR. &
720	ANY( rcz(1:nturbines) == 9999999.9_wp ) ) THEN
721
722	message_string = 'rcx, rcy, rcz ' // &
723	'have to be given for each turbine.'
724	CALL message( 'wtm_check_parameters', 'PA0463', 1, 2, 0, 6, 0 )
725
726	ENDIF
727
728
729	END SUBROUTINE wtm_check_parameters
730
731
732	!------------------------------------------------------------------------------!
733	! Description:
734	! ------------
735	!> Allocate wind turbine model arrays
736	!------------------------------------------------------------------------------!
737	SUBROUTINE wtm_init_arrays
738
739
740	IMPLICIT NONE
741
742	REAL(wp) :: delta_r_factor !<
743	REAL(wp) :: delta_r_init !<
744
745	!
746	!-- To be able to allocate arrays with dimension of rotor rings and segments,
747	!-- the maximum possible numbers of rings and segments have to be calculated:
748
749	ALLOCATE( nrings(1:nturbines) )
750	ALLOCATE( delta_r(1:nturbines) )
751
752	nrings(:) = 0
753	delta_r(:) = 0.0_wp
754
755	!
756	!-- Thickness (radial) of each ring and length (tangential) of each segment:
757	delta_r_factor = segment_width
758	delta_t_factor = segment_length
759	delta_r_init = delta_r_factor * MIN( dx, dy, dz(1))
760
761	DO inot = 1, nturbines
762	!
763	!-- Determine number of rings:
764	nrings(inot) = NINT( rr(inot) / delta_r_init )
765
766	delta_r(inot) = rr(inot) / nrings(inot)
767
768	ENDDO
769
770	nrings_max = MAXVAL(nrings)
771
772	ALLOCATE( nsegs(1:nrings_max,1:nturbines) )
773	ALLOCATE( nsegs_total(1:nturbines) )
774
775	nsegs(:,:) = 0
776	nsegs_total(:) = 0
777
778
779	DO inot = 1, nturbines
780	DO ring = 1, nrings(inot)
781	!
782	!-- Determine number of segments for each ring:
783	nsegs(ring,inot) = MAX( 8, CEILING( delta_r_factor * pi * &
784	( 2.0_wp * ring - 1.0_wp ) / &
785	delta_t_factor ) )
786	ENDDO
787	!
788	!-- Total sum of all rotor segments:
789	nsegs_total(inot) = SUM( nsegs(:,inot) )
790
791	ENDDO
792
793	!
794	!-- Maximum number of segments per ring:
795	nsegs_max = MAXVAL(nsegs)
796
797	!!
798	!!-- TODO: Folgendes im Header ausgeben!
799	! IF ( myid == 0 ) THEN
800	! PRINT*, 'nrings(1) = ', nrings(1)
801	! PRINT*, '--------------------------------------------------'
802	! PRINT*, 'nsegs(:,1) = ', nsegs(:,1)
803	! PRINT*, '--------------------------------------------------'
804	! PRINT*, 'nrings_max = ', nrings_max
805	! PRINT*, 'nsegs_max = ', nsegs_max
806	! PRINT*, 'nsegs_total(1) = ', nsegs_total(1)
807	! ENDIF
808
809
810	!
811	!-- Allocate 1D arrays (dimension = number of turbines)
812	ALLOCATE( i_hub(1:nturbines) )
813	ALLOCATE( i_smear(1:nturbines) )
814	ALLOCATE( j_hub(1:nturbines) )
815	ALLOCATE( j_smear(1:nturbines) )
816	ALLOCATE( k_hub(1:nturbines) )
817	ALLOCATE( k_smear(1:nturbines) )
818	ALLOCATE( torque_total(1:nturbines) )
819	ALLOCATE( thrust_rotor(1:nturbines) )
820
821	!
822	!-- Allocation of the 1D arrays for yaw control
823	ALLOCATE( yawdir(1:nturbines) )
824	ALLOCATE( u_inflow(1:nturbines) )
825	ALLOCATE( wdir(1:nturbines) )
826	ALLOCATE( u_inflow_l(1:nturbines) )
827	ALLOCATE( wdir_l(1:nturbines) )
828	ALLOCATE( phi_yaw_l(1:nturbines) )
829
830	!
831	!-- Allocate 1D arrays (dimension = number of rotor segments)
832	ALLOCATE( alpha_attack(1:nsegs_max) )
833	ALLOCATE( chord(1:nsegs_max) )
834	ALLOCATE( phi_rel(1:nsegs_max) )
835	ALLOCATE( thrust_seg(1:nsegs_max) )
836	ALLOCATE( torque_seg_y(1:nsegs_max) )
837	ALLOCATE( torque_seg_z(1:nsegs_max) )
838	ALLOCATE( turb_cd(1:nsegs_max) )
839	ALLOCATE( turb_cl(1:nsegs_max) )
840	ALLOCATE( vrel(1:nsegs_max) )
841	ALLOCATE( vtheta(1:nsegs_max) )
842
843	!
844	!-- Allocate 2D arrays (dimension = number of rotor rings and segments)
845	ALLOCATE( rbx(1:nrings_max,1:nsegs_max) )
846	ALLOCATE( rby(1:nrings_max,1:nsegs_max) )
847	ALLOCATE( rbz(1:nrings_max,1:nsegs_max) )
848	ALLOCATE( thrust_ring(1:nrings_max,1:nsegs_max) )
849	ALLOCATE( torque_ring_y(1:nrings_max,1:nsegs_max) )
850	ALLOCATE( torque_ring_z(1:nrings_max,1:nsegs_max) )
851
852	!
853	!-- Allocate additional 2D arrays
854	ALLOCATE( rotx(1:nturbines,1:3) )
855	ALLOCATE( roty(1:nturbines,1:3) )
856	ALLOCATE( rotz(1:nturbines,1:3) )
857
858	!
859	!-- Allocate 3D arrays (dimension = number of grid points)
860	ALLOCATE( nac_cd_surf(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
861	ALLOCATE( rot_tend_x(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
862	ALLOCATE( rot_tend_y(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
863	ALLOCATE( rot_tend_z(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
864	ALLOCATE( thrust(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
865	ALLOCATE( torque_y(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
866	ALLOCATE( torque_z(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
867	ALLOCATE( tow_cd_surf(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
868
869	!
870	!-- Allocate additional 3D arrays
871	ALLOCATE( u_int(1:nturbines,1:nrings_max,1:nsegs_max) )
872	ALLOCATE( u_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) )
873	ALLOCATE( v_int(1:nturbines,1:nrings_max,1:nsegs_max) )
874	ALLOCATE( v_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) )
875	ALLOCATE( w_int(1:nturbines,1:nrings_max,1:nsegs_max) )
876	ALLOCATE( w_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) )
877
878	!
879	!-- All of the arrays are initialized with a value of zero:
880	i_hub(:) = 0
881	i_smear(:) = 0
882	j_hub(:) = 0
883	j_smear(:) = 0
884	k_hub(:) = 0
885	k_smear(:) = 0
886
887	torque_total(:) = 0.0_wp
888	thrust_rotor(:) = 0.0_wp
889
890	IF ( TRIM( initializing_actions ) /= 'read_restart_data' ) THEN
891	omega_gen(:) = 0.0_wp
892	omega_gen_old(:) = 0.0_wp
893	omega_gen_f(:) = 0.0_wp
894	omega_gen_f_old(:) = 0.0_wp
895	pitch_add_old(:) = 0.0_wp
896	torque_gen(:) = 0.0_wp
897	torque_gen_old(:) = 0.0_wp
898	ENDIF
899
900	yawdir(:) = 0.0_wp
901	wdir_l(:) = 0.0_wp
902	wdir(:) = 0.0_wp
903	u_inflow(:) = 0.0_wp
904	u_inflow_l(:) = 0.0_wp
905	phi_yaw_l(:) = 0.0_wp
906
907	!
908	!-- Allocate 1D arrays (dimension = number of rotor segments)
909	alpha_attack(:) = 0.0_wp
910	chord(:) = 0.0_wp
911	phi_rel(:) = 0.0_wp
912	thrust_seg(:) = 0.0_wp
913	torque_seg_y(:) = 0.0_wp
914	torque_seg_z(:) = 0.0_wp
915	turb_cd(:) = 0.0_wp
916	turb_cl(:) = 0.0_wp
917	vrel(:) = 0.0_wp
918	vtheta(:) = 0.0_wp
919
920	rbx(:,:) = 0.0_wp
921	rby(:,:) = 0.0_wp
922	rbz(:,:) = 0.0_wp
923	thrust_ring(:,:) = 0.0_wp
924	torque_ring_y(:,:) = 0.0_wp
925	torque_ring_z(:,:) = 0.0_wp
926
927	rotx(:,:) = 0.0_wp
928	roty(:,:) = 0.0_wp
929	rotz(:,:) = 0.0_wp
930
931	nac_cd_surf(:,:,:) = 0.0_wp
932	rot_tend_x(:,:,:) = 0.0_wp
933	rot_tend_y(:,:,:) = 0.0_wp
934	rot_tend_z(:,:,:) = 0.0_wp
935	thrust(:,:,:) = 0.0_wp
936	torque_y(:,:,:) = 0.0_wp
937	torque_z(:,:,:) = 0.0_wp
938	tow_cd_surf(:,:,:) = 0.0_wp
939
940	u_int(:,:,:) = 0.0_wp
941	u_int_1_l(:,:,:) = 0.0_wp
942	v_int(:,:,:) = 0.0_wp
943	v_int_1_l(:,:,:) = 0.0_wp
944	w_int(:,:,:) = 0.0_wp
945	w_int_1_l(:,:,:) = 0.0_wp
946
947
948	END SUBROUTINE wtm_init_arrays
949
950
951	!------------------------------------------------------------------------------!
952	! Description:
953	! ------------
954	!> Initialization of the wind turbine model
955	!------------------------------------------------------------------------------!
956	SUBROUTINE wtm_init
957
958
959	USE control_parameters, &
960	ONLY: dz_stretch_level_start
961
962	IMPLICIT NONE
963
964	INTEGER(iwp) :: i !< running index
965	INTEGER(iwp) :: j !< running index
966	INTEGER(iwp) :: k !< running index
967
968	!
969	!-- Help variables for the smearing function
970	REAL(wp) :: eps_kernel !<
971
972	!
973	!-- Help variables for calculation of the tower drag
974	INTEGER(iwp) :: tower_n !<
975	INTEGER(iwp) :: tower_s !<
976	!
977	!-- Help variables for the calulaction of the nacelle drag
978	INTEGER(iwp) :: i_ip !<
979	INTEGER(iwp) :: i_ipg !<
980
981	REAL(wp) :: yvalue
982	REAL(wp) :: dy_int !<
983	REAL(wp) :: dz_int !<
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	ALLOCATE( index_nacb(1:nturbines) )
993	ALLOCATE( index_nacl(1:nturbines) )
994	ALLOCATE( index_nacr(1:nturbines) )
995	ALLOCATE( index_nact(1:nturbines) )
996
997	!
998	!------------------------------------------------------------------------------!
999	!-- Calculation of parameters for the regularization kernel
1000	!-- (smearing of the forces)
1001	!------------------------------------------------------------------------------!
1002	!
1003	!-- In the following, some of the required parameters for the smearing will
1004	!-- be calculated:
1005
1006	!-- The kernel is set equal to twice the grid spacing which has turned out to
1007	!-- be a reasonable value (see e.g. Troldborg et al. (2013), Wind Energy,
1008	!-- DOI: 10.1002/we.1608):
1009	eps_kernel = 2.0_wp * dx
1010	!
1011	!-- The zero point (eps_min) of the polynomial function must be the following
1012	!-- if the integral of the polynomial function (for values < eps_min) shall
1013	!-- be equal to the integral of the Gaussian function used before:
1014	eps_min = ( 105.0_wp / 32.0_wp )*( 1.0_wp / 3.0_wp ) &
1015	pi*( 1.0_wp / 6.0_wp ) eps_kernel
1016	!
1017	!-- Stretching (non-uniform grid spacing) is not considered in the wind
1018	!-- turbine model. Therefore, vertical stretching has to be applied above
1019	!-- the area where the wtm is active. ABS (...) is required because the
1020	!-- default value of dz_stretch_level_start is -9999999.9_wp (negative).
1021	IF ( ABS( dz_stretch_level_start(1) ) <= MAXVAL(rcz(1:nturbines)) + &
1022	MAXVAL(rr(1:nturbines)) + &
1023	eps_min) THEN
1024	WRITE( message_string, * ) 'The lowest level where vertical ', &
1025	'stretching is applied &have to be ', &
1026	'greater than ',MAXVAL(rcz(1:nturbines)) +&
1027	MAXVAL(rr(1:nturbines)) + eps_min
1028	CALL message( 'wtm_init', 'PA0484', 1, 2, 0, 6, 0 )
1029	ENDIF
1030	!
1031	!-- Square of eps_min:
1032	eps_min2 = eps_min**2
1033	!
1034	!-- Parameters in the polynomial function:
1035	pol_a = 1.0_wp / eps_min**4
1036	pol_b = 2.0_wp / eps_min**2
1037	!
1038	!-- Normalization factor which is the inverse of the integral of the smearing
1039	!-- function:
1040	eps_factor = 105.0_wp / ( 32.0_wp * pi * eps_min**3 )
1041
1042	!-- Change tilt angle to rad:
1043	tilt = tilt * pi / 180.0_wp
1044
1045	!
1046	!-- Change yaw angle to rad:
1047	IF ( TRIM( initializing_actions ) /= 'read_restart_data' ) THEN
1048	phi_yaw(:) = phi_yaw(:) * pi / 180.0_wp
1049	ENDIF
1050
1051
1052	DO inot = 1, nturbines
1053	!
1054	!-- Rotate the rotor coordinates in case yaw and tilt are defined
1055	CALL wtm_rotate_rotor( inot )
1056
1057	!
1058	!-- Determine the indices of the hub height
1059	i_hub(inot) = INT( rcx(inot) / dx )
1060	j_hub(inot) = INT( ( rcy(inot) + 0.5_wp * dy ) / dy )
1061	k_hub(inot) = INT( ( rcz(inot) + 0.5_wp * dz(1) ) / dz(1) )
1062
1063	!
1064	!-- Determining the area to which the smearing of the forces is applied.
1065	!-- As smearing now is effectively applied only for distances smaller than
1066	!-- eps_min, the smearing area can be further limited and regarded as a
1067	!-- function of eps_min:
1068	i_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dx )
1069	j_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dy )
1070	k_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dz(1) )
1071
1072	ENDDO
1073
1074	!
1075	!-- Call the wtm_init_speed_control subroutine and calculate the local
1076	!-- omega_rot for the respective processor.
1077	IF ( speed_control) THEN
1078
1079	CALL wtm_speed_control
1080
1081	IF ( TRIM( initializing_actions ) == 'read_restart_data' ) THEN
1082
1083	DO inot = 1, nturbines
1084
1085	IF ( nxl > i_hub(inot) ) THEN
1086	torque_gen(inot) = 0.0_wp
1087	omega_gen_f(inot) = 0.0_wp
1088	omega_rot_l(inot) = 0.0_wp
1089	ENDIF
1090
1091	IF ( nxr < i_hub(inot) ) THEN
1092	torque_gen(inot) = 0.0_wp
1093	omega_gen_f(inot) = 0.0_wp
1094	omega_rot_l(inot) = 0.0_wp
1095	ENDIF
1096
1097	IF ( nys > j_hub(inot) ) THEN
1098	torque_gen(inot) = 0.0_wp
1099	omega_gen_f(inot) = 0.0_wp
1100	omega_rot_l(inot) = 0.0_wp
1101	ENDIF
1102
1103	IF ( nyn < j_hub(inot) ) THEN
1104	torque_gen(inot) = 0.0_wp
1105	omega_gen_f(inot) = 0.0_wp
1106	omega_rot_l(inot) = 0.0_wp
1107	ENDIF
1108
1109	IF ( ( nxl <= i_hub(inot) ) .AND. ( nxr >= i_hub(inot) ) ) THEN
1110	IF ( ( nys <= j_hub(inot) ) .AND. ( nyn >= j_hub(inot) ) ) THEN
1111
1112	omega_rot_l(inot) = omega_gen(inot) / gear_ratio
1113
1114	ENDIF
1115	ENDIF
1116
1117	END DO
1118
1119	ENDIF
1120
1121	ENDIF
1122
1123	!
1124	!------------------------------------------------------------------------------!
1125	!-- Determine the area within each grid cell that overlaps with the area
1126	!-- of the nacelle and the tower (needed for calculation of the forces)
1127	!------------------------------------------------------------------------------!
1128	!
1129	!-- Note: so far this is only a 2D version, in that the mean flow is
1130	!-- perpendicular to the rotor area.
1131
1132	!
1133	!-- Allocation of the array containing information on the intersection points
1134	!-- between rotor disk and the numerical grid:
1135	upper_end = ( ny + 1 ) * 10000
1136
1137	ALLOCATE( circle_points(1:2,1:upper_end) )
1138
1139	circle_points(:,:) = 0.0_wp
1140
1141
1142	DO inot = 1, nturbines ! loop over number of turbines
1143	!
1144	!-- Determine the grid index (u-grid) that corresponds to the location of
1145	!-- the rotor center (reduces the amount of calculations in the case that
1146	!-- the mean flow is perpendicular to the rotor area):
1147	i = i_hub(inot)
1148
1149	!
1150	!-- Determine the left and the right edge of the nacelle (corresponding
1151	!-- grid point indices):
1152	index_nacl(inot) = INT( ( rcy(inot) - rnac(inot) + 0.5_wp * dy ) / dy )
1153	index_nacr(inot) = INT( ( rcy(inot) + rnac(inot) + 0.5_wp * dy ) / dy )
1154	!
1155	!-- Determine the bottom and the top edge of the nacelle (corresponding
1156	!-- grid point indices).The grid point index has to be increased by 1, as
1157	!-- the first level for the u-component (index 0) is situated below the
1158	!-- surface. All points between z=0 and z=dz/s would already be contained
1159	!-- in grid box 1.
1160	index_nacb(inot) = INT( ( rcz(inot) - rnac(inot) ) / dz(1) ) + 1
1161	index_nact(inot) = INT( ( rcz(inot) + rnac(inot) ) / dz(1) ) + 1
1162
1163	!
1164	!-- Determine the indices of the grid boxes containing the left and
1165	!-- the right boundaries of the tower:
1166	tower_n = ( rcy(inot) + 0.5_wp * dtow(inot) - 0.5_wp * dy ) / dy
1167	tower_s = ( rcy(inot) - 0.5_wp * dtow(inot) - 0.5_wp * dy ) / dy
1168
1169	!
1170	!-- Determine the fraction of the grid box area overlapping with the tower
1171	!-- area and multiply it with the drag of the tower:
1172	IF ( ( nxlg <= i ) .AND. ( nxrg >= i ) ) THEN
1173
1174	DO j = nys, nyn
1175	!
1176	!-- Loop from south to north boundary of tower
1177	IF ( ( j >= tower_s ) .AND. ( j <= tower_n ) ) THEN
1178
1179	DO k = nzb, nzt
1180
1181	IF ( k == k_hub(inot) ) THEN
1182	IF ( tower_n - tower_s >= 1 ) THEN
1183	!
1184	!-- leftmost and rightmost grid box:
1185	IF ( j == tower_s ) THEN
1186	tow_cd_surf(k,j,i) = ( rcz(inot) - &
1187	( k_hub(inot) * dz(1) - 0.5_wp * dz(1) ) )*& ! extension in z-direction
1188	( ( tower_s + 1.0_wp + 0.5_wp ) * dy - &
1189	( rcy(inot) - 0.5_wp * dtow(inot) ) ) * & ! extension in y-direction
1190	turb_cd_tower(inot)
1191	ELSEIF ( j == tower_n ) THEN
1192	tow_cd_surf(k,j,i) = ( rcz(inot) - &
1193	( k_hub(inot) * dz(1) - 0.5_wp * dz(1) ) )*& ! extension in z-direction
1194	( ( rcy(inot) + 0.5_wp * dtow(inot) ) - &
1195	( tower_n + 0.5_wp ) * dy ) * & ! extension in y-direction
1196	turb_cd_tower(inot)
1197	!
1198	!-- grid boxes inbetween
1199	!-- (where tow_cd_surf = grid box area):
1200	ELSE
1201	tow_cd_surf(k,j,i) = ( rcz(inot) - &
1202	( k_hub(inot) * dz(1) - 0.5_wp * dz(1) ) )*&
1203	dy * turb_cd_tower(inot)
1204	ENDIF
1205	!
1206	!-- tower lies completely within one grid box:
1207	ELSE
1208	tow_cd_surf(k,j,i) = ( rcz(inot) - ( k_hub(inot) * &
1209	dz(1) - 0.5_wp * dz(1) ) ) * &
1210	dtow(inot) * turb_cd_tower(inot)
1211	ENDIF
1212	!
1213	!-- In case that k is smaller than k_hub the following actions
1214	!-- are carried out:
1215	ELSEIF ( k < k_hub(inot) ) THEN
1216
1217	IF ( ( tower_n - tower_s ) >= 1 ) THEN
1218	!
1219	!-- leftmost and rightmost grid box:
1220	IF ( j == tower_s ) THEN
1221	tow_cd_surf(k,j,i) = dz(1) * ( &
1222	( tower_s + 1 + 0.5_wp ) * dy - &
1223	( rcy(inot) - 0.5_wp * dtow(inot) ) &
1224	) * turb_cd_tower(inot)
1225	ELSEIF ( j == tower_n ) THEN
1226	tow_cd_surf(k,j,i) = dz(1) * ( &
1227	( rcy(inot) + 0.5_wp * dtow(inot) ) - &
1228	( tower_n + 0.5_wp ) * dy &
1229	) * turb_cd_tower(inot)
1230	!
1231	!-- grid boxes inbetween
1232	!-- (where tow_cd_surf = grid box area):
1233	ELSE
1234	tow_cd_surf(k,j,i) = dz(1) * dy * &
1235	turb_cd_tower(inot)
1236	ENDIF
1237	!
1238	!-- tower lies completely within one grid box:
1239	ELSE
1240	tow_cd_surf(k,j,i) = dz(1) * dtow(inot) * &
1241	turb_cd_tower(inot)
1242	ENDIF ! end if larger than grid box
1243
1244	ENDIF ! end if k == k_hub
1245
1246	ENDDO ! end loop over k
1247
1248	ENDIF ! end if inside north and south boundary of tower
1249
1250	ENDDO ! end loop over j
1251
1252	ENDIF ! end if hub inside domain + ghostpoints
1253
1254
1255	CALL exchange_horiz( tow_cd_surf, nbgp )
1256
1257	!
1258	!-- Calculation of the nacelle area
1259	!-- CAUTION: Currently disabled due to segmentation faults on the FLOW HPC
1260	!-- cluster (Oldenburg)
1261	!!
1262	!!-- Tabulate the points on the circle that are required in the following for
1263	!!-- the calculation of the Riemann integral (node points; they are called
1264	!!-- circle_points in the following):
1265	!
1266	! dy_int = dy / 10000.0_wp
1267	!
1268	! DO i_ip = 1, upper_end
1269	! yvalue = dy_int * ( i_ip - 0.5_wp ) + 0.5_wp * dy !<--- segmentation fault
1270	! sqrt_arg = rnac(inot)2 - ( yvalue - rcy(inot) )2 !<--- segmentation fault
1271	! IF ( sqrt_arg >= 0.0_wp ) THEN
1272	!!
1273	!!-- bottom intersection point
1274	! circle_points(1,i_ip) = rcz(inot) - SQRT( sqrt_arg )
1275	!!
1276	!!-- top intersection point
1277	! circle_points(2,i_ip) = rcz(inot) + SQRT( sqrt_arg ) !<--- segmentation fault
1278	! ELSE
1279	! circle_points(:,i_ip) = -111111 !<--- segmentation fault
1280	! ENDIF
1281	! ENDDO
1282	!
1283	!
1284	! DO j = nys, nyn
1285	!!
1286	!!-- In case that the grid box is located completely outside the nacelle
1287	!!-- (y) it can automatically be stated that there is no overlap between
1288	!!-- the grid box and the nacelle and consequently we can set
1289	!!-- nac_cd_surf(:,j,i) = 0.0:
1290	! IF ( ( j >= index_nacl(inot) ) .AND. ( j <= index_nacr(inot) ) ) THEN
1291	! DO k = nzb+1, nzt
1292	!!
1293	!!-- In case that the grid box is located completely outside the
1294	!!-- nacelle (z) it can automatically be stated that there is no
1295	!!-- overlap between the grid box and the nacelle and consequently
1296	!!-- we can set nac_cd_surf(k,j,i) = 0.0:
1297	! IF ( ( k >= index_nacb(inot) ) .OR. &
1298	! ( k <= index_nact(inot) ) ) THEN
1299	!!
1300	!!-- For all other cases Riemann integrals are calculated.
1301	!!-- Here, the points on the circle that have been determined
1302	!!-- above are used in order to calculate the overlap between the
1303	!!-- gridbox and the nacelle area (area approached by 10000
1304	!!-- rectangulars dz_int * dy_int):
1305	! DO i_ipg = 1, 10000
1306	! dz_int = dz
1307	! i_ip = j * 10000 + i_ipg
1308	!!
1309	!!-- Determine the vertical extension dz_int of the circle
1310	!!-- within the current grid box:
1311	! IF ( ( circle_points(2,i_ip) < zw(k) ) .AND. & !<--- segmentation fault
1312	! ( circle_points(2,i_ip) >= zw(k-1) ) ) THEN
1313	! dz_int = dz_int - & !<--- segmentation fault
1314	! ( zw(k) - circle_points(2,i_ip) )
1315	! ENDIF
1316	! IF ( ( circle_points(1,i_ip) <= zw(k) ) .AND. & !<--- segmentation fault
1317	! ( circle_points(1,i_ip) > zw(k-1) ) ) THEN
1318	! dz_int = dz_int - &
1319	! ( circle_points(1,i_ip) - zw(k-1) )
1320	! ENDIF
1321	! IF ( zw(k-1) > circle_points(2,i_ip) ) THEN
1322	! dz_int = 0.0_wp
1323	! ENDIF
1324	! IF ( zw(k) < circle_points(1,i_ip) ) THEN
1325	! dz_int = 0.0_wp
1326	! ENDIF
1327	! IF ( ( nxlg <= i ) .AND. ( nxrg >= i ) ) THEN
1328	! nac_cd_surf(k,j,i) = nac_cd_surf(k,j,i) + & !<--- segmentation fault
1329	! dy_int * dz_int * turb_cd_nacelle(inot)
1330	! ENDIF
1331	! ENDDO
1332	! ENDIF
1333	! ENDDO
1334	! ENDIF
1335	!
1336	! ENDDO
1337	!
1338	! CALL exchange_horiz( nac_cd_surf, nbgp ) !<--- segmentation fault
1339
1340	ENDDO ! end of loop over turbines
1341
1342	tow_cd_surf = tow_cd_surf / ( dx * dy * dz(1) ) ! Normalize tower drag
1343	nac_cd_surf = nac_cd_surf / ( dx * dy * dz(1) ) ! Normalize nacelle drag
1344
1345	CALL wtm_read_blade_tables
1346
1347	END SUBROUTINE wtm_init
1348
1349
1350	!------------------------------------------------------------------------------!
1351	! Description:
1352	! ------------
1353	!> Read in layout of the rotor blade , the lift and drag tables
1354	!> and the distribution of lift and drag tables along the blade
1355	!------------------------------------------------------------------------------!
1356	!
1357	SUBROUTINE wtm_read_blade_tables
1358
1359
1360	IMPLICIT NONE
1361
1362	INTEGER(iwp) :: ii !< running index
1363	INTEGER(iwp) :: jj !< running index
1364
1365	INTEGER(iwp) :: ierrn !<
1366
1367	CHARACTER(200) :: chmess !< Read in string
1368
1369	INTEGER(iwp) :: dlen !< no. rows of local table
1370	INTEGER(iwp) :: dlenbl !< no. rows of cd, cl table
1371	INTEGER(iwp) :: ialpha !< table position of current alpha value
1372	INTEGER(iwp) :: iialpha !<
1373	INTEGER(iwp) :: iir !<
1374	INTEGER(iwp) :: radres !< radial resolution
1375	INTEGER(iwp) :: t1 !< no. of airfoil
1376	INTEGER(iwp) :: t2 !< no. of airfoil
1377	INTEGER(iwp) :: trow !<
1378	INTEGER(iwp) :: dlenbl_int !< no. rows of interpolated cd, cl tables
1379
1380	REAL(wp) :: alpha_attack_i !<
1381	REAL(wp) :: weight_a !<
1382	REAL(wp) :: weight_b !<
1383
1384	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: ttoint1 !<
1385	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: ttoint2 !<
1386
1387	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd_sel1 !<
1388	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd_sel2 !<
1389	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl_sel1 !<
1390	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl_sel2 !<
1391	REAL(wp), DIMENSION(:), ALLOCATABLE :: read_cl_cd !< read in var array
1392
1393	REAL(wp), DIMENSION(:), ALLOCATABLE :: alpha_attack_tab !<
1394	REAL(wp), DIMENSION(:), ALLOCATABLE :: trad1 !<
1395	REAL(wp), DIMENSION(:), ALLOCATABLE :: trad2 !<
1396	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cd_table !<
1397	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cl_table !<
1398
1399	ALLOCATE ( read_cl_cd(1:2*nairfoils+1) )
1400
1401	!
1402	!-- Read in the distribution of lift and drag tables along the blade, the
1403	!-- layout of the rotor blade and the lift and drag tables:
1404
1405	OPEN ( 90, FILE='WTM_DATA', STATUS='OLD', FORM='FORMATTED', IOSTAT=ierrn )
1406
1407	IF ( ierrn /= 0 ) THEN
1408	message_string = 'file WTM_DATA does not exist'
1409	CALL message( 'wtm_init', 'PA0464', 1, 2, 0, 6, 0 )
1410	ENDIF
1411	!
1412	!-- Read distribution table:
1413
1414	dlen = 0
1415
1416	READ ( 90, '(3/)' )
1417
1418	rloop3: DO
1419	READ ( 90, *, IOSTAT=ierrn ) chmess
1420	IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop3
1421	dlen = dlen + 1
1422	ENDDO rloop3
1423
1424	ALLOCATE( trad1(1:dlen), trad2(1:dlen), ttoint1(1:dlen), ttoint2(1:dlen))
1425
1426	DO jj = 1,dlen+1
1427	BACKSPACE ( 90, IOSTAT=ierrn )
1428	ENDDO
1429
1430	DO jj = 1,dlen
1431	READ ( 90, * ) trad1(jj), trad2(jj), ttoint1(jj), ttoint2(jj)
1432	ENDDO
1433
1434	!
1435	!-- Read layout table:
1436
1437	dlen = 0
1438
1439	READ ( 90, '(3/)')
1440
1441	rloop1: DO
1442	READ ( 90, *, IOSTAT=ierrn ) chmess
1443	IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop1
1444	dlen = dlen + 1
1445	ENDDO rloop1
1446
1447	ALLOCATE( lrd(1:dlen), ard(1:dlen), crd(1:dlen) )
1448	DO jj = 1, dlen+1
1449	BACKSPACE ( 90, IOSTAT=ierrn )
1450	ENDDO
1451	DO jj = 1, dlen
1452	READ ( 90, * ) lrd(jj), ard(jj), crd(jj)
1453	ENDDO
1454
1455	!
1456	!-- Read tables (turb_cl(alpha),turb_cd(alpha) for the different profiles:
1457
1458	dlen = 0
1459
1460	READ ( 90, '(3/)' )
1461
1462	rloop2: DO
1463	READ ( 90, *, IOSTAT=ierrn ) chmess
1464	IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop2
1465	dlen = dlen + 1
1466	ENDDO rloop2
1467
1468	ALLOCATE( alpha_attack_tab(1:dlen), turb_cl_table(1:dlen,1:nairfoils), &
1469	turb_cd_table(1:dlen,1:nairfoils) )
1470
1471	DO jj = 1,dlen+1
1472	BACKSPACE ( 90, IOSTAT=ierrn )
1473	ENDDO
1474
1475	DO jj = 1,dlen
1476	READ ( 90, * ) read_cl_cd
1477	alpha_attack_tab(jj) = read_cl_cd(1)
1478	DO ii= 1, nairfoils
1479	turb_cl_table(jj,ii) = read_cl_cd(ii*2)
1480	turb_cd_table(jj,ii) = read_cl_cd(ii*2+1)
1481	ENDDO
1482
1483	ENDDO
1484
1485	dlenbl = dlen
1486
1487	CLOSE ( 90 )
1488
1489	!
1490	!-- For each possible radial position (resolution: 0.1 m --> 631 values if rr(1)=63m)
1491	!-- and each possible angle of attack (resolution: 0.1 degrees --> 3601 values!)
1492	!-- determine the lift and drag coefficient by interpolating between the
1493	!-- tabulated values of each table (interpolate to current angle of attack)
1494	!-- and between the tables (interpolate to current radial position):
1495
1496	ALLOCATE( turb_cl_sel1(1:dlenbl) )
1497	ALLOCATE( turb_cl_sel2(1:dlenbl) )
1498	ALLOCATE( turb_cd_sel1(1:dlenbl) )
1499	ALLOCATE( turb_cd_sel2(1:dlenbl) )
1500
1501	radres = INT( rr(1) * 10.0_wp ) + 1_iwp
1502	dlenbl_int = INT( 360.0_wp / accu_cl_cd_tab ) + 1_iwp
1503
1504	ALLOCATE( turb_cl_tab(1:dlenbl_int,1:radres) )
1505	ALLOCATE( turb_cd_tab(1:dlenbl_int,1:radres) )
1506
1507	DO iir = 1, radres ! loop over radius
1508
1509	cur_r = ( iir - 1_iwp ) * 0.1_wp
1510	!
1511	!-- Find position in table 1
1512	lct = MINLOC( ABS( trad1 - cur_r ) )
1513	! lct(1) = lct(1)
1514
1515	IF ( ( trad1(lct(1)) - cur_r ) .GT. 0.0 ) THEN
1516	lct(1) = lct(1) - 1
1517	ENDIF
1518
1519	trow = lct(1)
1520	!
1521	!-- Calculate weights for radius interpolation
1522	weight_a = ( trad2(trow) - cur_r ) / ( trad2(trow) - trad1(trow) )
1523	weight_b = ( cur_r - trad1(trow) ) / ( trad2(trow) - trad1(trow) )
1524	t1 = ttoint1(trow)
1525	t2 = ttoint2(trow)
1526
1527	IF ( t1 .EQ. t2 ) THEN ! if both are the same, the weights are NaN
1528	weight_a = 0.5_wp ! then do interpolate in between same twice
1529	weight_b = 0.5_wp ! using 0.5 as weight
1530	ENDIF
1531
1532	IF ( t1 == 0 .AND. t2 == 0 ) THEN
1533	turb_cd_sel1 = 0.0_wp
1534	turb_cd_sel2 = 0.0_wp
1535	turb_cl_sel1 = 0.0_wp
1536	turb_cl_sel2 = 0.0_wp
1537
1538	turb_cd_tab(1,iir) = 0.0_wp ! For -180Â° (iialpha=1) the values
1539	turb_cl_tab(1,iir) = 0.0_wp ! for each radius has to be set
1540	! explicitly
1541	ELSE
1542	turb_cd_sel1 = turb_cd_table(:,t1)
1543	turb_cd_sel2 = turb_cd_table(:,t2)
1544	turb_cl_sel1 = turb_cl_table(:,t1)
1545	turb_cl_sel2 = turb_cl_table(:,t2)
1546	!
1547	!-- For -180Â° (iialpha=1) the values for each radius has to be set
1548	!-- explicitly
1549	turb_cd_tab(1,iir) = ( weight_a * turb_cd_table(1,t1) + weight_b &
1550	* turb_cd_table(1,t2) )
1551	turb_cl_tab(1,iir) = ( weight_a * turb_cl_table(1,t1) + weight_b &
1552	* turb_cl_table(1,t2) )
1553	ENDIF
1554
1555	DO iialpha = 2, dlenbl_int ! loop over angles
1556
1557	alpha_attack_i = -180.0_wp + REAL( iialpha-1 ) * accu_cl_cd_tab
1558	ialpha = 1
1559
1560	DO WHILE ( ( alpha_attack_i > alpha_attack_tab(ialpha) ) .AND. (ialpha <= dlen ) )
1561	ialpha = ialpha + 1
1562	ENDDO
1563
1564	!
1565	!-- Interpolation of lift and drag coefficiencts on fine grid of radius
1566	!-- segments and angles of attack
1567
1568	turb_cl_tab(iialpha,iir) = ( alpha_attack_tab(ialpha) - &
1569	alpha_attack_i ) / &
1570	( alpha_attack_tab(ialpha) - &
1571	alpha_attack_tab(ialpha-1) ) * &
1572	( weight_a * turb_cl_sel1(ialpha-1) + &
1573	weight_b * turb_cl_sel2(ialpha-1) ) +&
1574	( alpha_attack_i - &
1575	alpha_attack_tab(ialpha-1) ) / &
1576	( alpha_attack_tab(ialpha) - &
1577	alpha_attack_tab(ialpha-1) ) * &
1578	( weight_a * turb_cl_sel1(ialpha) + &
1579	weight_b * turb_cl_sel2(ialpha) )
1580	turb_cd_tab(iialpha,iir) = ( alpha_attack_tab(ialpha) - &
1581	alpha_attack_i ) / &
1582	( alpha_attack_tab(ialpha) - &
1583	alpha_attack_tab(ialpha-1) ) * &
1584	( weight_a * turb_cd_sel1(ialpha-1) + &
1585	weight_b * turb_cd_sel2(ialpha-1) ) +&
1586	( alpha_attack_i - &
1587	alpha_attack_tab(ialpha-1) ) / &
1588	( alpha_attack_tab(ialpha) - &
1589	alpha_attack_tab(ialpha-1) ) * &
1590	( weight_a * turb_cd_sel1(ialpha) + &
1591	weight_b * turb_cd_sel2(ialpha) )
1592
1593	ENDDO ! end loop over angles of attack
1594
1595	ENDDO ! end loop over radius
1596
1597
1598	END SUBROUTINE wtm_read_blade_tables
1599
1600
1601	!------------------------------------------------------------------------------!
1602	! Description:
1603	! ------------
1604	!> The projection matrix for the coordinate system of therotor disc in respect
1605	!> to the yaw and tilt angle of the rotor is calculated
1606	!------------------------------------------------------------------------------!
1607	SUBROUTINE wtm_rotate_rotor( inot )
1608
1609
1610	IMPLICIT NONE
1611
1612	INTEGER(iwp) :: inot
1613	!
1614	!-- Calculation of the rotation matrix for the application of the tilt to
1615	!-- the rotors
1616	rot_eigen_rad(1) = SIN( phi_yaw(inot) ) ! x-component of the radial eigenvector
1617	rot_eigen_rad(2) = COS( phi_yaw(inot) ) ! y-component of the radial eigenvector
1618	rot_eigen_rad(3) = 0.0_wp ! z-component of the radial eigenvector
1619
1620	rot_eigen_azi(1) = 0.0_wp ! x-component of the azimuth eigenvector
1621	rot_eigen_azi(2) = 0.0_wp ! y-component of the azimuth eigenvector
1622	rot_eigen_azi(3) = 1.0_wp ! z-component of the azimuth eigenvector
1623
1624	rot_eigen_nor(1) = COS( phi_yaw(inot) ) ! x-component of the normal eigenvector
1625	rot_eigen_nor(2) = -SIN( phi_yaw(inot) ) ! y-component of the normal eigenvector
1626	rot_eigen_nor(3) = 0.0_wp ! z-component of the normal eigenvector
1627
1628	!
1629	!-- Calculation of the coordinate transformation matrix to apply a tilt to
1630	!-- the rotor. If tilt = 0, rot_coord_trans is a unit matrix.
1631
1632	rot_coord_trans(inot,1,1) = rot_eigen_rad(1)*2 &
1633	( 1.0_wp - COS( tilt ) ) + COS( tilt )
1634	rot_coord_trans(inot,1,2) = rot_eigen_rad(1) * rot_eigen_rad(2) * &
1635	( 1.0_wp - COS( tilt ) ) - &
1636	rot_eigen_rad(3) * SIN( tilt )
1637	rot_coord_trans(inot,1,3) = rot_eigen_rad(1) * rot_eigen_rad(3) * &
1638	( 1.0_wp - COS( tilt ) ) + &
1639	rot_eigen_rad(2) * SIN( tilt )
1640	rot_coord_trans(inot,2,1) = rot_eigen_rad(2) * rot_eigen_rad(1) * &
1641	( 1.0_wp - COS( tilt ) ) + &
1642	rot_eigen_rad(3) * SIN( tilt )
1643	rot_coord_trans(inot,2,2) = rot_eigen_rad(2)*2 &
1644	( 1.0_wp - COS( tilt ) ) + COS( tilt )
1645	rot_coord_trans(inot,2,3) = rot_eigen_rad(2) * rot_eigen_rad(3) * &
1646	( 1.0_wp - COS( tilt ) ) - &
1647	rot_eigen_rad(1) * SIN( tilt )
1648	rot_coord_trans(inot,3,1) = rot_eigen_rad(3) * rot_eigen_rad(1) * &
1649	( 1.0_wp - COS( tilt ) ) - &
1650	rot_eigen_rad(2) * SIN( tilt )
1651	rot_coord_trans(inot,3,2) = rot_eigen_rad(3) * rot_eigen_rad(2) * &
1652	( 1.0_wp - COS( tilt ) ) + &
1653	rot_eigen_rad(1) * SIN( tilt )
1654	rot_coord_trans(inot,3,3) = rot_eigen_rad(3)*2 &
1655	( 1.0_wp - COS( tilt ) ) + COS( tilt )
1656
1657	!
1658	!-- Vectors for the Transformation of forces from the rotor's spheric
1659	!-- coordinate system to the cartesian coordinate system
1660	rotx(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_nor )
1661	roty(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_rad )
1662	rotz(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_azi )
1663
1664	END SUBROUTINE wtm_rotate_rotor
1665
1666
1667	!------------------------------------------------------------------------------!
1668	! Description:
1669	! ------------
1670	!> Calculation of the forces generated by the wind turbine
1671	!------------------------------------------------------------------------------!
1672	SUBROUTINE wtm_forces
1673
1674
1675	IMPLICIT NONE
1676
1677	CHARACTER (LEN=4) :: turbine_id
1678
1679	INTEGER(iwp) :: i, j, k !< loop indices
1680	INTEGER(iwp) :: inot !< turbine loop index (turbine id)
1681	INTEGER(iwp) :: iialpha, iir !<
1682	INTEGER(iwp) :: rseg !<
1683	INTEGER(iwp) :: ring !<
1684	INTEGER(iwp) :: ii, jj, kk !<
1685
1686	REAL(wp) :: flag !< flag to mask topography grid points
1687	REAL(wp) :: sin_rot, cos_rot !<
1688	REAL(wp) :: sin_yaw, cos_yaw !<
1689
1690	REAL(wp) :: aa, bb, cc, dd !< interpolation distances
1691	REAL(wp) :: gg !< interpolation volume var
1692
1693	REAL(wp) :: dist_u_3d, dist_v_3d, dist_w_3d !< smearing distances
1694
1695
1696	!
1697	! Variables for pitch control
1698	LOGICAL :: pitch_sw = .FALSE.
1699
1700	INTEGER(iwp), DIMENSION(1) :: lct = 0
1701	REAL(wp), DIMENSION(1) :: rad_d = 0.0_wp
1702
1703	REAL(wp) :: tl_factor !< factor for tip loss correction
1704
1705
1706	CALL cpu_log( log_point_s(61), 'wtm_forces', 'start' )
1707
1708
1709	IF ( simulated_time >= time_turbine_on ) THEN
1710
1711	!
1712	!-- Set forces to zero for each new time step:
1713	thrust(:,:,:) = 0.0_wp
1714	torque_y(:,:,:) = 0.0_wp
1715	torque_z(:,:,:) = 0.0_wp
1716	torque_total(:) = 0.0_wp
1717	rot_tend_x(:,:,:) = 0.0_wp
1718	rot_tend_y(:,:,:) = 0.0_wp
1719	rot_tend_z(:,:,:) = 0.0_wp
1720	thrust_rotor(:) = 0.0_wp
1721	!
1722	!-- Loop over number of turbines:
1723	DO inot = 1, nturbines
1724
1725	cos_yaw = COS(phi_yaw(inot))
1726	sin_yaw = SIN(phi_yaw(inot))
1727	!
1728	!-- Loop over rings of each turbine:
1729	DO ring = 1, nrings(inot)
1730
1731	thrust_seg(:) = 0.0_wp
1732	torque_seg_y(:) = 0.0_wp
1733	torque_seg_z(:) = 0.0_wp
1734	!
1735	!-- Determine distance between each ring (center) and the hub:
1736	cur_r = (ring - 0.5_wp) * delta_r(inot)
1737
1738	!
1739	!-- Loop over segments of each ring of each turbine:
1740	DO rseg = 1, nsegs(ring,inot)
1741	!
1742	!-- !-----------------------------------------------------------!
1743	!-- !-- Determine coordinates of the ring segments --!
1744	!-- !-----------------------------------------------------------!
1745	!
1746	!-- Determine angle of ring segment towards zero degree angle of
1747	!-- rotor system (at zero degree rotor direction vectors aligned
1748	!-- with y-axis):
1749	phi_rotor = rseg * 2.0_wp * pi / nsegs(ring,inot)
1750	cos_rot = COS( phi_rotor )
1751	sin_rot = SIN( phi_rotor )
1752
1753	!-- Now the direction vectors can be determined with respect to
1754	!-- the yaw and tilt angle:
1755	re(1) = cos_rot * sin_yaw
1756	re(2) = cos_rot * cos_yaw
1757	re(3) = sin_rot
1758
1759	rote = MATMUL( rot_coord_trans(inot,:,:), re )
1760	!
1761	!-- Coordinates of the single segments (center points):
1762	rbx(ring,rseg) = rcx(inot) + cur_r * rote(1)
1763	rby(ring,rseg) = rcy(inot) + cur_r * rote(2)
1764	rbz(ring,rseg) = rcz(inot) + cur_r * rote(3)
1765
1766	!-- !-----------------------------------------------------------!
1767	!-- !-- Interpolation of the velocity components from the --!
1768	!-- !-- cartesian grid point to the coordinates of each ring --!
1769	!-- !-- segment (follows a method used in the particle model) --!
1770	!-- !-----------------------------------------------------------!
1771
1772	u_int(inot,ring,rseg) = 0.0_wp
1773	u_int_1_l(inot,ring,rseg) = 0.0_wp
1774
1775	v_int(inot,ring,rseg) = 0.0_wp
1776	v_int_1_l(inot,ring,rseg) = 0.0_wp
1777
1778	w_int(inot,ring,rseg) = 0.0_wp
1779	w_int_1_l(inot,ring,rseg) = 0.0_wp
1780
1781	!
1782	!-- Interpolation of the u-component:
1783
1784	ii = rbx(ring,rseg) * ddx
1785	jj = ( rby(ring,rseg) - 0.5_wp * dy ) * ddy
1786	kk = ( rbz(ring,rseg) + 0.5_wp * dz(1) ) / dz(1)
1787	!
1788	!-- Interpolate only if all required information is available on
1789	!-- the current PE:
1790	IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN
1791	IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN
1792
1793	aa = ( ( ii + 1 ) * dx - rbx(ring,rseg) ) * &
1794	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1795	bb = ( rbx(ring,rseg) - ii * dx ) * &
1796	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1797	cc = ( ( ii+1 ) * dx - rbx(ring,rseg) ) * &
1798	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1799	dd = ( rbx(ring,rseg) - ii * dx ) * &
1800	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1801	gg = dx * dy
1802
1803	u_int_l = ( aa * u(kk,jj,ii) + &
1804	bb * u(kk,jj,ii+1) + &
1805	cc * u(kk,jj+1,ii) + &
1806	dd * u(kk,jj+1,ii+1) &
1807	) / gg
1808
1809	u_int_u = ( aa * u(kk+1,jj,ii) + &
1810	bb * u(kk+1,jj,ii+1) + &
1811	cc * u(kk+1,jj+1,ii) + &
1812	dd * u(kk+1,jj+1,ii+1) &
1813	) / gg
1814
1815	u_int_1_l(inot,ring,rseg) = u_int_l + &
1816	( rbz(ring,rseg) - zu(kk) ) / dz(1) * &
1817	( u_int_u - u_int_l )
1818
1819	ELSE
1820	u_int_1_l(inot,ring,rseg) = 0.0_wp
1821	ENDIF
1822	ELSE
1823	u_int_1_l(inot,ring,rseg) = 0.0_wp
1824	ENDIF
1825
1826
1827	!
1828	!-- Interpolation of the v-component:
1829	ii = ( rbx(ring,rseg) - 0.5_wp * dx ) * ddx
1830	jj = rby(ring,rseg) * ddy
1831	kk = ( rbz(ring,rseg) + 0.5_wp * dz(1) ) / dz(1)
1832	!
1833	!-- Interpolate only if all required information is available on
1834	!-- the current PE:
1835	IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN
1836	IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN
1837
1838	aa = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1839	( ( jj + 1 ) * dy - rby(ring,rseg) )
1840	bb = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1841	( ( jj + 1 ) * dy - rby(ring,rseg) )
1842	cc = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1843	( rby(ring,rseg) - jj * dy )
1844	dd = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1845	( rby(ring,rseg) - jj * dy )
1846	gg = dx * dy
1847
1848	v_int_l = ( aa * v(kk,jj,ii) + &
1849	bb * v(kk,jj,ii+1) + &
1850	cc * v(kk,jj+1,ii) + &
1851	dd * v(kk,jj+1,ii+1) &
1852	) / gg
1853
1854	v_int_u = ( aa * v(kk+1,jj,ii) + &
1855	bb * v(kk+1,jj,ii+1) + &
1856	cc * v(kk+1,jj+1,ii) + &
1857	dd * v(kk+1,jj+1,ii+1) &
1858	) / gg
1859
1860	v_int_1_l(inot,ring,rseg) = v_int_l + &
1861	( rbz(ring,rseg) - zu(kk) ) / dz(1) * &
1862	( v_int_u - v_int_l )
1863
1864	ELSE
1865	v_int_1_l(inot,ring,rseg) = 0.0_wp
1866	ENDIF
1867	ELSE
1868	v_int_1_l(inot,ring,rseg) = 0.0_wp
1869	ENDIF
1870
1871
1872	!
1873	!-- Interpolation of the w-component:
1874	ii = ( rbx(ring,rseg) - 0.5_wp * dx ) * ddx
1875	jj = ( rby(ring,rseg) - 0.5_wp * dy ) * ddy
1876	kk = rbz(ring,rseg) / dz(1)
1877	!
1878	!-- Interpolate only if all required information is available on
1879	!-- the current PE:
1880	IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN
1881	IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN
1882
1883	aa = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1884	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1885	bb = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1886	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1887	cc = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1888	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1889	dd = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1890	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1891	gg = dx * dy
1892
1893	w_int_l = ( aa * w(kk,jj,ii) + &
1894	bb * w(kk,jj,ii+1) + &
1895	cc * w(kk,jj+1,ii) + &
1896	dd * w(kk,jj+1,ii+1) &
1897	) / gg
1898
1899	w_int_u = ( aa * w(kk+1,jj,ii) + &
1900	bb * w(kk+1,jj,ii+1) + &
1901	cc * w(kk+1,jj+1,ii) + &
1902	dd * w(kk+1,jj+1,ii+1) &
1903	) / gg
1904
1905	w_int_1_l(inot,ring,rseg) = w_int_l + &
1906	( rbz(ring,rseg) - zw(kk) ) / dz(1) * &
1907	( w_int_u - w_int_l )
1908	ELSE
1909	w_int_1_l(inot,ring,rseg) = 0.0_wp
1910	ENDIF
1911	ELSE
1912	w_int_1_l(inot,ring,rseg) = 0.0_wp
1913	ENDIF
1914
1915	ENDDO
1916	ENDDO
1917
1918	ENDDO
1919
1920	!
1921	!-- Exchange between PEs (information required on each PE):
1922	#if defined( __parallel )
1923	CALL MPI_ALLREDUCE( u_int_1_l, u_int, nturbines * MAXVAL(nrings) * &
1924	MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr )
1925	CALL MPI_ALLREDUCE( v_int_1_l, v_int, nturbines * MAXVAL(nrings) * &
1926	MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr )
1927	CALL MPI_ALLREDUCE( w_int_1_l, w_int, nturbines * MAXVAL(nrings) * &
1928	MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr )
1929	#else
1930	u_int = u_int_1_l
1931	v_int = v_int_1_l
1932	w_int = w_int_1_l
1933	#endif
1934
1935
1936	!
1937	!-- Loop over number of turbines:
1938
1939	DO inot = 1, nturbines
1940	pit_loop: DO
1941
1942	IF ( pitch_sw ) THEN
1943	torque_total(inot) = 0.0_wp
1944	thrust_rotor(inot) = 0.0_wp
1945	pitch_add(inot) = pitch_add(inot) + 0.25_wp
1946	! IF ( myid == 0 ) PRINT*, 'Pitch', inot, pitch_add(inot)
1947	ELSE
1948	cos_yaw = COS(phi_yaw(inot))
1949	sin_yaw = SIN(phi_yaw(inot))
1950	IF ( pitch_control ) THEN
1951	pitch_add(inot) = MAX(pitch_add_old(inot) - pitch_rate * &
1952	dt_3d , 0.0_wp )
1953	ENDIF
1954	ENDIF
1955
1956	!
1957	!-- Loop over rings of each turbine:
1958	DO ring = 1, nrings(inot)
1959	!
1960	!-- Determine distance between each ring (center) and the hub:
1961	cur_r = (ring - 0.5_wp) * delta_r(inot)
1962	!
1963	!-- Loop over segments of each ring of each turbine:
1964	DO rseg = 1, nsegs(ring,inot)
1965	!
1966	!-- Determine angle of ring segment towards zero degree angle of
1967	!-- rotor system (at zero degree rotor direction vectors aligned
1968	!-- with y-axis):
1969	phi_rotor = rseg * 2.0_wp * pi / nsegs(ring,inot)
1970	cos_rot = COS(phi_rotor)
1971	sin_rot = SIN(phi_rotor)
1972	!
1973	!-- Now the direction vectors can be determined with respect to
1974	!-- the yaw and tilt angle:
1975	re(1) = cos_rot * sin_yaw
1976	re(2) = cos_rot * cos_yaw
1977	re(3) = sin_rot
1978
1979	! The current unit vector in azimuthal direction:
1980	rea(1) = - sin_rot * sin_yaw
1981	rea(2) = - sin_rot * cos_yaw
1982	rea(3) = cos_rot
1983
1984	!
1985	!-- To respect the yawing angle for the calculations of
1986	!-- velocities and forces the unit vectors perpendicular to the
1987	!-- rotor area in direction of the positive yaw angle are defined:
1988	ren(1) = cos_yaw
1989	ren(2) = - sin_yaw
1990	ren(3) = 0.0_wp
1991	!
1992	!-- Multiplication with the coordinate transformation matrix
1993	!-- gives the final unit vector with consideration of the rotor
1994	!-- tilt:
1995	rote = MATMUL( rot_coord_trans(inot,:,:), re )
1996	rota = MATMUL( rot_coord_trans(inot,:,:), rea )
1997	rotn = MATMUL( rot_coord_trans(inot,:,:), ren )
1998	!
1999	!-- Coordinates of the single segments (center points):
2000	rbx(ring,rseg) = rcx(inot) + cur_r * rote(1)
2001
2002	rby(ring,rseg) = rcy(inot) + cur_r * rote(2)
2003
2004	rbz(ring,rseg) = rcz(inot) + cur_r * rote(3)
2005
2006	!
2007	!-- !-----------------------------------------------------------!
2008	!-- !-- Calculation of various angles and relative velocities --!
2009	!-- !-----------------------------------------------------------!
2010	!
2011	!-- In the following the 3D-velocity field is projected its
2012	!-- components perpendicular and parallel to the rotor area
2013	!-- The calculation of forces will be done in the rotor-
2014	!-- coordinates y' and z.
2015	!-- The yaw angle will be reintroduced when the force is applied
2016	!-- on the hydrodynamic equations
2017	!
2018	!-- Projection of the xy-velocities relative to the rotor area
2019	!
2020	!-- Velocity perpendicular to the rotor area:
2021	u_rot = u_int(inot,ring,rseg)*rotn(1) + &
2022	v_int(inot,ring,rseg)*rotn(2) + &
2023	w_int(inot,ring,rseg)*rotn(3)
2024	!
2025	!-- Projection of the 3D-velocity vector in the azimuthal
2026	!-- direction:
2027	vtheta(rseg) = rota(1) * u_int(inot,ring,rseg) + &
2028	rota(2) * v_int(inot,ring,rseg) + &
2029	rota(3) * w_int(inot,ring,rseg)
2030	!
2031	!-- Determination of the angle phi_rel between the rotor plane
2032	!-- and the direction of the flow relative to the rotor:
2033
2034	phi_rel(rseg) = ATAN( u_rot / &
2035	( omega_rot(inot) * cur_r - &
2036	vtheta(rseg) ) )
2037
2038	!
2039	!-- Interpolation of the local pitch angle from tabulated values
2040	!-- to the current radial position:
2041
2042	lct=minloc(ABS(cur_r-lrd))
2043	rad_d=cur_r-lrd(lct)
2044
2045	IF (cur_r == 0.0_wp) THEN
2046	alpha_attack(rseg) = 0.0_wp
2047	ELSE IF (cur_r >= lrd(size(ard))) THEN
2048	alpha_attack(rseg) = ( ard(size(ard)) + &
2049	ard(size(ard)-1) ) / 2.0_wp
2050	ELSE
2051	alpha_attack(rseg) = ( ard(lct(1)) * &
2052	( ( lrd(lct(1)+1) - cur_r ) / &
2053	( lrd(lct(1)+1) - lrd(lct(1)) ) &
2054	) ) + ( ard(lct(1)+1) * &
2055	( ( cur_r - lrd(lct(1)) ) / &
2056	( lrd(lct(1)+1) - lrd(lct(1)) ) ) )
2057	ENDIF
2058
2059	!
2060	!-- In Fortran radian instead of degree is used as unit for all
2061	!-- angles. Therefore, a transformation from angles given in
2062	!-- degree to angles given in radian is necessary here:
2063	alpha_attack(rseg) = alpha_attack(rseg) * &
2064	( (2.0_wp*pi) / 360.0_wp )
2065	!
2066	!-- Substraction of the local pitch angle to obtain the local
2067	!-- angle of attack:
2068	alpha_attack(rseg) = phi_rel(rseg) - alpha_attack(rseg)
2069	!
2070	!-- Preliminary transformation back from angles given in radian
2071	!-- to angles given in degree:
2072	alpha_attack(rseg) = alpha_attack(rseg) * &
2073	( 360.0_wp / (2.0_wp*pi) )
2074	!
2075	!-- Correct with collective pitch angle:
2076	alpha_attack(rseg) = alpha_attack(rseg) - pitch_add(inot)
2077
2078	!
2079	!-- Determination of the magnitude of the flow velocity relative
2080	!-- to the rotor:
2081	vrel(rseg) = SQRT( u_rot**2 + &
2082	( omega_rot(inot) * cur_r - &
2083	vtheta(rseg) )**2 )
2084
2085	!
2086	!-- !-----------------------------------------------------------!
2087	!-- !-- Interpolation of chord as well as lift and drag --!
2088	!-- !-- coefficients from tabulated values --!
2089	!-- !-----------------------------------------------------------!
2090
2091	!
2092	!-- Interpolation of the chord_length from tabulated values to
2093	!-- the current radial position:
2094
2095	IF (cur_r == 0.0_wp) THEN
2096	chord(rseg) = 0.0_wp
2097	ELSE IF (cur_r >= lrd(size(crd))) THEN
2098	chord(rseg) = (crd(size(crd)) + ard(size(crd)-1)) / 2.0_wp
2099	ELSE
2100	chord(rseg) = ( crd(lct(1)) * &
2101	( ( lrd(lct(1)+1) - cur_r ) / &
2102	( lrd(lct(1)+1) - lrd(lct(1)) ) ) ) + &
2103	( crd(lct(1)+1) * &
2104	( ( cur_r-lrd(lct(1)) ) / &
2105	( lrd(lct(1)+1) - lrd(lct(1)) ) ) )
2106	ENDIF
2107
2108	!
2109	!-- Determine index of current angle of attack, needed for
2110	!-- finding the appropriate interpolated values of the lift and
2111	!-- drag coefficients (-180.0 degrees = 1, +180.0 degrees = 3601,
2112	!-- so one index every 0.1 degrees):
2113	iialpha = CEILING( ( alpha_attack(rseg) + 180.0_wp ) &
2114	* ( 1.0_wp / accu_cl_cd_tab ) ) + 1.0_wp
2115	!
2116	!-- Determine index of current radial position, needed for
2117	!-- finding the appropriate interpolated values of the lift and
2118	!-- drag coefficients (one index every 0.1 m):
2119	iir = CEILING( cur_r * 10.0_wp )
2120	!
2121	!-- Read in interpolated values of the lift and drag coefficients
2122	!-- for the current radial position and angle of attack:
2123	turb_cl(rseg) = turb_cl_tab(iialpha,iir)
2124	turb_cd(rseg) = turb_cd_tab(iialpha,iir)
2125
2126	!
2127	!-- Final transformation back from angles given in degree to
2128	!-- angles given in radian:
2129	alpha_attack(rseg) = alpha_attack(rseg) * &
2130	( (2.0_wp*pi) / 360.0_wp )
2131
2132	IF ( tl_cor ) THEN
2133
2134	!-- Tip loss correction following Schito
2135	!-- Schito applies the tip loss correction only to the lift force
2136	!-- Therefore, the tip loss correction is only applied to the lift
2137	!-- coefficient and not to the drag coefficient in our case
2138	!--
2139	tl_factor = ( 2.0 / pi ) * &
2140	ACOS( EXP( -1.0 * ( 3.0 * ( rr(inot) - cur_r ) / &
2141	( 2.0 * cur_r * abs( sin( phi_rel(rseg) ) ) ) ) ) )
2142
2143	turb_cl(rseg) = tl_factor * turb_cl(rseg)
2144
2145	ENDIF
2146	!
2147	!-- !-----------------------------------------------------!
2148	!-- !-- Calculation of the forces --!
2149	!-- !-----------------------------------------------------!
2150
2151	!
2152	!-- Calculate the pre_factor for the thrust and torque forces:
2153
2154	pre_factor = 0.5_wp * (vrel(rseg)*2) 3.0_wp * &
2155	chord(rseg) * delta_r(inot) / nsegs(ring,inot)
2156
2157	!
2158	!-- Calculate the thrust force (x-component of the total force)
2159	!-- for each ring segment:
2160	thrust_seg(rseg) = pre_factor * &
2161	( turb_cl(rseg) * COS(phi_rel(rseg)) + &
2162	turb_cd(rseg) * SIN(phi_rel(rseg)) )
2163
2164	!
2165	!-- Determination of the second of the additional forces acting
2166	!-- on the flow in the azimuthal direction: force vector as basis
2167	!-- for torque (torque itself would be the vector product of the
2168	!-- radius vector and the force vector):
2169	torque_seg = pre_factor * &
2170	( turb_cl(rseg) * SIN(phi_rel(rseg)) - &
2171	turb_cd(rseg) * COS(phi_rel(rseg)) )
2172	!
2173	!-- Decomposition of the force vector into two parts:
2174	!-- One acting along the y-direction and one acting along the
2175	!-- z-direction of the rotor coordinate system:
2176
2177	torque_seg_y(rseg) = -torque_seg * sin_rot
2178	torque_seg_z(rseg) = torque_seg * cos_rot
2179
2180	!
2181	!-- Add the segment thrust to the thrust of the whole rotor
2182	thrust_rotor(inot) = thrust_rotor(inot) + &
2183	thrust_seg(rseg)
2184
2185
2186	torque_total(inot) = torque_total(inot) + (torque_seg * cur_r)
2187
2188	ENDDO !-- end of loop over ring segments
2189
2190	!
2191	!-- Restore the forces into arrays containing all the segments of
2192	!-- each ring:
2193	thrust_ring(ring,:) = thrust_seg(:)
2194	torque_ring_y(ring,:) = torque_seg_y(:)
2195	torque_ring_z(ring,:) = torque_seg_z(:)
2196
2197
2198	ENDDO !-- end of loop over rings
2199
2200
2201	CALL cpu_log( log_point_s(62), 'wtm_controller', 'start' )
2202
2203
2204	IF ( speed_control ) THEN
2205	!
2206	!-- Calculation of the current generator speed for rotor speed control
2207
2208	!
2209	!-- The acceleration of the rotor speed is calculated from
2210	!-- the force balance of the accelerating torque
2211	!-- and the torque of the rotating rotor and generator
2212	om_rate = ( torque_total(inot) * air_dens * gear_eff - &
2213	gear_ratio * torque_gen_old(inot) ) / &
2214	( inertia_rot + &
2215	gear_ratio * gear_ratio * inertia_gen ) * dt_3d
2216
2217	!
2218	!-- The generator speed is given by the product of gear gear_ratio
2219	!-- and rotor speed
2220	omega_gen(inot) = gear_ratio * ( omega_rot(inot) + om_rate )
2221
2222	ENDIF
2223
2224	IF ( pitch_control ) THEN
2225
2226	!
2227	!-- If the current generator speed is above rated, the pitch is not
2228	!-- saturated and the change from the last time step is within the
2229	!-- maximum pitch rate, then the pitch loop is repeated with a pitch
2230	!-- gain
2231	IF ( ( omega_gen(inot) > rated_genspeed ) .AND. &
2232	( pitch_add(inot) < 25.0_wp ) .AND. &
2233	( pitch_add(inot) < pitch_add_old(inot) + &
2234	pitch_rate * dt_3d ) ) THEN
2235	pitch_sw = .TRUE.
2236	!
2237	!-- Go back to beginning of pit_loop
2238	CYCLE pit_loop
2239	ENDIF
2240
2241	!
2242	!-- The current pitch is saved for the next time step
2243	pitch_add_old(inot) = pitch_add(inot)
2244	pitch_sw = .FALSE.
2245	ENDIF
2246	EXIT pit_loop
2247	ENDDO pit_loop ! Recursive pitch control loop
2248
2249
2250	!
2251	!-- Call the rotor speed controller
2252
2253	IF ( speed_control ) THEN
2254	!
2255	!-- Find processor at i_hub, j_hub
2256	IF ( ( nxl <= i_hub(inot) ) .AND. ( nxr >= i_hub(inot) ) ) &
2257	THEN
2258	IF ( ( nys <= j_hub(inot) ) .AND. ( nyn >= j_hub(inot) ) )&
2259	THEN
2260	CALL wtm_speed_control( inot )
2261	ENDIF
2262	ENDIF
2263
2264	ENDIF
2265
2266
2267	CALL cpu_log( log_point_s(62), 'wtm_controller', 'stop' )
2268
2269	CALL cpu_log( log_point_s(63), 'wtm_smearing', 'start' )
2270
2271
2272	!-- !-----------------------------------------------------------------!
2273	!-- !-- Regularization kernel --!
2274	!-- !-- Smearing of the forces and interpolation to cartesian grid --!
2275	!-- !-----------------------------------------------------------------!
2276	!
2277	!-- The aerodynamic blade forces need to be distributed smoothly on
2278	!-- several mesh points in order to avoid singular behaviour
2279	!
2280	!-- Summation over sum of weighted forces. The weighting factor
2281	!-- (calculated in user_init) includes information on the distance
2282	!-- between the center of the grid cell and the rotor segment under
2283	!-- consideration
2284	!
2285	!-- To save computing time, apply smearing only for the relevant part
2286	!-- of the model domain:
2287	!
2288	!--
2289	!-- Calculation of the boundaries:
2290	i_smear(inot) = CEILING( ( rr(inot) * ABS( roty(inot,1) ) + &
2291	eps_min ) / dx )
2292	j_smear(inot) = CEILING( ( rr(inot) * ABS( roty(inot,2) ) + &
2293	eps_min ) / dy )
2294
2295	DO i = MAX( nxl, i_hub(inot) - i_smear(inot) ), &
2296	MIN( nxr, i_hub(inot) + i_smear(inot) )
2297	DO j = MAX( nys, j_hub(inot) - j_smear(inot) ), &
2298	MIN( nyn, j_hub(inot) + j_smear(inot) )
2299	! DO k = MAX( nzb_u_inner(j,i)+1, k_hub(inot) - k_smear(inot) ), &
2300	! k_hub(inot) + k_smear(inot)
2301	DO k = nzb+1, k_hub(inot) + k_smear(inot)
2302	DO ring = 1, nrings(inot)
2303	DO rseg = 1, nsegs(ring,inot)
2304	!
2305	!-- Predetermine flag to mask topography
2306	flag = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_0(k,j,i), 1 ) )
2307
2308	!
2309	!-- Determine the square of the distance between the
2310	!-- current grid point and each rotor area segment:
2311	dist_u_3d = ( i * dx - rbx(ring,rseg) )**2 + &
2312	( j * dy + 0.5_wp * dy - rby(ring,rseg) )**2 + &
2313	( k * dz(1) - 0.5_wp * dz(1) - rbz(ring,rseg) )**2
2314	dist_v_3d = ( i * dx + 0.5_wp * dx - rbx(ring,rseg) )**2 + &
2315	( j * dy - rby(ring,rseg) )**2 + &
2316	( k * dz(1) - 0.5_wp * dz(1) - rbz(ring,rseg) )**2
2317	dist_w_3d = ( i * dx + 0.5_wp * dx - rbx(ring,rseg) )**2 + &
2318	( j * dy + 0.5_wp * dy - rby(ring,rseg) )**2 + &
2319	( k * dz(1) - rbz(ring,rseg) )**2
2320
2321	!
2322	!-- 3D-smearing of the forces with a polynomial function
2323	!-- (much faster than the old Gaussian function), using
2324	!-- some parameters that have been calculated in user_init.
2325	!-- The function is only similar to Gaussian function for
2326	!-- squared distances <= eps_min2:
2327	IF ( dist_u_3d <= eps_min2 ) THEN
2328	thrust(k,j,i) = thrust(k,j,i) + &
2329	thrust_ring(ring,rseg) * &
2330	( ( pol_a * dist_u_3d - pol_b ) * &
2331	dist_u_3d + 1.0_wp ) * eps_factor *&
2332	flag
2333	ENDIF
2334	IF ( dist_v_3d <= eps_min2 ) THEN
2335	torque_y(k,j,i) = torque_y(k,j,i) + &
2336	torque_ring_y(ring,rseg) * &
2337	( ( pol_a * dist_v_3d - pol_b ) * &
2338	dist_v_3d + 1.0_wp ) * eps_factor * &
2339	flag
2340	ENDIF
2341	IF ( dist_w_3d <= eps_min2 ) THEN
2342	torque_z(k,j,i) = torque_z(k,j,i) + &
2343	torque_ring_z(ring,rseg) * &
2344	( ( pol_a * dist_w_3d - pol_b ) * &
2345	dist_w_3d + 1.0_wp ) * eps_factor * &
2346	flag
2347	ENDIF
2348
2349	ENDDO ! End of loop over rseg
2350	ENDDO ! End of loop over ring
2351
2352	!
2353	!-- Rotation of force components:
2354	rot_tend_x(k,j,i) = rot_tend_x(k,j,i) + ( &
2355	thrust(k,j,i)*rotx(inot,1) + &
2356	torque_y(k,j,i)*roty(inot,1) + &
2357	torque_z(k,j,i)*rotz(inot,1) &
2358	) * flag
2359
2360	rot_tend_y(k,j,i) = rot_tend_y(k,j,i) + ( &
2361	thrust(k,j,i)*rotx(inot,2) + &
2362	torque_y(k,j,i)*roty(inot,2) + &
2363	torque_z(k,j,i)*rotz(inot,2) &
2364	) * flag
2365
2366	rot_tend_z(k,j,i) = rot_tend_z(k,j,i) + ( &
2367	thrust(k,j,i)*rotx(inot,3) + &
2368	torque_y(k,j,i)*roty(inot,3) + &
2369	torque_z(k,j,i)*rotz(inot,3) &
2370	) * flag
2371
2372	ENDDO ! End of loop over k
2373	ENDDO ! End of loop over j
2374	ENDDO ! End of loop over i
2375
2376	CALL cpu_log( log_point_s(63), 'wtm_smearing', 'stop' )
2377
2378	ENDDO !-- end of loop over turbines
2379
2380
2381	IF ( yaw_control ) THEN
2382	!
2383	!-- Allocate arrays for yaw control at first call
2384	!-- Can't be allocated before dt_3d is set
2385	IF ( start_up ) THEN
2386	WDLON = NINT( 30.0_wp / dt_3d ) ! 30s running mean array
2387	ALLOCATE( wd30(1:nturbines,1:WDLON) )
2388	wd30 = 999.0_wp ! Set to dummy value
2389	ALLOCATE( wd30_l(1:WDLON) )
2390
2391	WDSHO = NINT( 2.0_wp / dt_3d ) ! 2s running mean array
2392	ALLOCATE( wd2(1:nturbines,1:WDSHO) )
2393	wd2 = 999.0_wp ! Set to dummy value
2394	ALLOCATE( wd2_l(1:WDSHO) )
2395	start_up = .FALSE.
2396	ENDIF
2397
2398	!
2399	!-- Calculate the inflow wind speed
2400	!--
2401	!-- Loop over number of turbines:
2402	DO inot = 1, nturbines
2403	!
2404	!-- Find processor at i_hub, j_hub
2405	IF ( ( nxl <= i_hub(inot) ) .AND. ( nxr >= i_hub(inot) ) ) &
2406	THEN
2407	IF ( ( nys <= j_hub(inot) ) .AND. ( nyn >= j_hub(inot) ) )&
2408	THEN
2409
2410	u_inflow_l(inot) = u(k_hub(inot),j_hub(inot),i_hub(inot))
2411
2412	wdir_l(inot) = -1.0_wp * ATAN2( &
2413	0.5_wp * ( v(k_hub(inot),j_hub(inot),i_hub(inot)+1) + &
2414	v(k_hub(inot),j_hub(inot),i_hub(inot)) ) , &
2415	0.5_wp * ( u(k_hub(inot),j_hub(inot)+1,i_hub(inot)) + &
2416	u(k_hub(inot),j_hub(inot),i_hub(inot)) ) )
2417
2418	CALL wtm_yawcontrol( inot )
2419
2420	phi_yaw_l(inot) = phi_yaw(inot)
2421
2422	ENDIF
2423	ENDIF
2424
2425	ENDDO !-- end of loop over turbines
2426
2427	!
2428	!-- Transfer of information to the other cpus
2429	#if defined( __parallel )
2430	CALL MPI_ALLREDUCE( u_inflow_l, u_inflow, nturbines, MPI_REAL, &
2431	MPI_SUM, comm2d, ierr )
2432	CALL MPI_ALLREDUCE( wdir_l, wdir, nturbines, MPI_REAL, MPI_SUM, &
2433	comm2d, ierr )
2434	CALL MPI_ALLREDUCE( phi_yaw_l, phi_yaw, nturbines, MPI_REAL, &
2435	MPI_SUM, comm2d, ierr )
2436	#else
2437	u_inflow = u_inflow_l
2438	wdir = wdir_l
2439	phi_yaw = phi_yaw_l
2440
2441
2442	#endif
2443	DO inot = 1, nturbines
2444	!
2445	!-- Update rotor orientation
2446	CALL wtm_rotate_rotor( inot )
2447
2448	ENDDO ! End of loop over turbines
2449
2450	ENDIF ! end of yaw control
2451
2452	IF ( speed_control ) THEN
2453	!
2454	!-- Transfer of information to the other cpus
2455	! CALL MPI_ALLREDUCE( omega_gen, omega_gen_old, nturbines, &
2456	! MPI_REAL,MPI_SUM, comm2d, ierr )
2457	#if defined( __parallel )
2458	CALL MPI_ALLREDUCE( torque_gen, torque_gen_old, nturbines, &
2459	MPI_REAL, MPI_SUM, comm2d, ierr )
2460	CALL MPI_ALLREDUCE( omega_rot_l, omega_rot, nturbines, &
2461	MPI_REAL, MPI_SUM, comm2d, ierr )
2462	CALL MPI_ALLREDUCE( omega_gen_f, omega_gen_f_old, nturbines, &
2463	MPI_REAL, MPI_SUM, comm2d, ierr )
2464	#else
2465	torque_gen_old = torque_gen
2466	omega_rot = omega_rot_l
2467	omega_gen_f_old = omega_gen_f
2468	#endif
2469
2470	ENDIF
2471
2472	DO inot = 1, nturbines
2473
2474	IF ( myid == 0 ) THEN
2475	IF ( openfile_turb_mod(400+inot)%opened ) THEN
2476	WRITE ( 400+inot, 106 ) simulated_time, omega_rot(inot), &
2477	omega_gen(inot), torque_gen_old(inot), &
2478	torque_total(inot), pitch_add(inot), &
2479	torque_gen_old(inot)omega_gen(inot)gen_eff, &
2480	torque_total(inot)omega_rot(inot)air_dens, &
2481	thrust_rotor(inot), &
2482	wdir(inot)*180.0_wp/pi, &
2483	(phi_yaw(inot))*180.0_wp/pi
2484
2485	ELSE
2486
2487	WRITE ( turbine_id,'(A2,I2.2)') '_T', inot
2488	OPEN ( 400+inot, FILE=( 'WTM_OUTPUT_DATA' // &
2489	TRIM( coupling_char ) // &
2490	turbine_id ), FORM='FORMATTED' )
2491	WRITE ( 400+inot, 105 ) inot
2492	WRITE ( 400+inot, 106 ) simulated_time, omega_rot(inot), &
2493	omega_gen(inot), torque_gen_old(inot), &
2494	torque_total(inot), pitch_add(inot), &
2495	torque_gen_old(inot)omega_gen(inot)gen_eff, &
2496	torque_total(inot)omega_rot(inot)air_dens, &
2497	thrust_rotor(inot), &
2498	wdir(inot)*180.0_wp/pi, &
2499	(phi_yaw(inot))*180.0_wp/pi
2500	ENDIF
2501	ENDIF
2502
2503	!-- Set open flag
2504	openfile_turb_mod(400+inot)%opened = .TRUE.
2505	ENDDO !-- end of loop over turbines
2506
2507	ENDIF
2508
2509	CALL cpu_log( log_point_s(61), 'wtm_forces', 'stop' )
2510
2511	!
2512	!-- Formats
2513	105 FORMAT ('Turbine control data for turbine ',I2,1X,':'/ &
2514	&'----------------------------------------'/ &
2515	&' Time RSpeed GSpeed ', &
2516	'GenTorque AeroTorque Pitch Power(Gen) Power(Rot) ', &
2517	'RotThrust WDirection YawOrient')
2518
2519	106 FORMAT (F9.3,2X,F7.3,2X,F7.2,2X,F9.1,3X,F9.1,1X,F6.2,2X,F10.1,2X, &
2520	F10.1,1X,F9.1,2X,F7.2,1X,F7.2)
2521
2522
2523	END SUBROUTINE wtm_forces
2524
2525
2526	!------------------------------------------------------------------------------!
2527	! Description:
2528	! ------------
2529	!> Yaw controller for the wind turbine model
2530	!------------------------------------------------------------------------------!
2531	SUBROUTINE wtm_yawcontrol( inot )
2532
2533	USE kinds
2534
2535	IMPLICIT NONE
2536
2537	INTEGER(iwp) :: inot
2538	INTEGER(iwp) :: i_wd_30
2539	REAL(wp) :: missal
2540
2541	i_wd_30 = 0_iwp
2542
2543	!
2544	!-- The yaw controller computes a 30s running mean of the wind direction.
2545	!-- If the difference between turbine alignment and wind direction exceeds
2546	!-- 5Â°, the turbine is yawed. The mechanism stops as soon as the 2s-running
2547	!-- mean of the missalignment is smaller than 0.5Â°.
2548	!-- Attention: If the timestep during the simulation changes significantly
2549	!-- the lengths of the running means change and it does not correspond to
2550	!-- 30s/2s anymore.
2551	!-- ! Needs to be modified for these situations !
2552	!-- For wind from the east, the averaging of the wind direction could cause
2553	!-- problems and the yaw controller is probably flawed. -> Routine for
2554	!-- averaging needs to be improved!
2555	!
2556	!-- Check if turbine is not yawing
2557	IF ( .NOT. doyaw(inot) ) THEN
2558	!
2559	!-- Write current wind direction into array
2560	wd30_l = wd30(inot,:)
2561	wd30_l = CSHIFT( wd30_l, SHIFT=-1 )
2562	wd30_l(1) = wdir(inot)
2563	!
2564	!-- Check if array is full ( no more dummies )
2565	IF ( .NOT. ANY( wd30_l == 999.) ) THEN
2566
2567	missal = SUM( wd30_l ) / SIZE( wd30_l ) - phi_yaw(inot)
2568	!
2569	!-- Check if turbine is missaligned by more than max_miss
2570	IF ( ABS( missal ) > max_miss ) THEN
2571	!
2572	!-- Check in which direction to yaw
2573	yawdir(inot) = SIGN( 1.0_wp, missal )
2574	!
2575	!-- Start yawing of turbine
2576	phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d
2577	doyaw(inot) = .TRUE.
2578	wd30_l = 999. ! fill with dummies again
2579	ENDIF
2580	ENDIF
2581
2582	wd30(inot,:) = wd30_l
2583
2584	!
2585	!-- If turbine is already yawing:
2586	!-- Initialize 2 s running mean and yaw until the missalignment is smaller
2587	!-- than min_miss
2588
2589	ELSE
2590	!
2591	!-- Initialize 2 s running mean
2592	wd2_l = wd2(inot,:)
2593	wd2_l = CSHIFT( wd2_l, SHIFT = -1 )
2594	wd2_l(1) = wdir(inot)
2595	!
2596	!-- Check if array is full ( no more dummies )
2597	IF ( .NOT. ANY( wd2_l == 999.0_wp ) ) THEN
2598	!
2599	!-- Calculate missalignment of turbine
2600	missal = SUM( wd2_l - phi_yaw(inot) ) / SIZE( wd2_l )
2601	!
2602	!-- Check if missalignment is still larger than 0.5 degree and if the
2603	!-- yaw direction is still right
2604	IF ( ( ABS( missal ) > min_miss ) .AND. &
2605	( yawdir(inot) == SIGN( 1.0_wp, missal ) ) ) THEN
2606	!
2607	!-- Continue yawing
2608	phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d
2609	ELSE
2610	!
2611	!-- Stop yawing
2612	doyaw(inot) = .FALSE.
2613	wd2_l = 999.0_wp ! fill with dummies again
2614	ENDIF
2615	ELSE
2616	!
2617	!-- Continue yawing
2618	phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d
2619	ENDIF
2620
2621	wd2(inot,:) = wd2_l
2622
2623	ENDIF
2624
2625	END SUBROUTINE wtm_yawcontrol
2626
2627
2628	!------------------------------------------------------------------------------!
2629	! Description:
2630	! ------------
2631	!> Initialization of the speed control
2632	!------------------------------------------------------------------------------!
2633	SUBROUTINE wtm_init_speed_control
2634
2635
2636	IMPLICIT NONE
2637
2638	!
2639	!-- If speed control is set, remaining variables and control_parameters for
2640	!-- the control algorithm are calculated
2641	!
2642	!-- Calculate slope constant for region 15
2643	slope15 = ( slope2 * min_reg2 * min_reg2 ) / ( min_reg2 - min_reg15 )
2644	!
2645	!-- Calculate upper limit of slipage region
2646	vs_sysp = rated_genspeed / 1.1_wp
2647	!
2648	!-- Calculate slope of slipage region
2649	slope25 = ( rated_power / rated_genspeed ) / &
2650	( rated_genspeed - vs_sysp )
2651	!
2652	!-- Calculate lower limit of slipage region
2653	min_reg25 = ( slope25 - SQRT( slope25 * ( slope25 - 4.0_wp * &
2654	slope2 * vs_sysp ) ) ) / &
2655	( 2.0_wp * slope2 )
2656	!
2657	!-- Frequency for the simple low pass filter
2658	Fcorner = 0.25_wp
2659	!
2660	!-- At the first timestep the torque is set to its maximum to prevent
2661	!-- an overspeeding of the rotor
2662	IF ( TRIM( initializing_actions ) /= 'read_restart_data' ) THEN
2663	torque_gen_old(:) = max_torque_gen
2664	ENDIF
2665
2666	END SUBROUTINE wtm_init_speed_control
2667
2668
2669	!------------------------------------------------------------------------------!
2670	! Description:
2671	! ------------
2672	!> Simple controller for the regulation of the rotor speed
2673	!------------------------------------------------------------------------------!
2674	SUBROUTINE wtm_speed_control( inot )
2675
2676
2677	IMPLICIT NONE
2678
2679	INTEGER(iwp) :: inot
2680
2681
2682
2683	!
2684	!-- The controller is based on the fortran script from Jonkman
2685	!-- et al. 2009 "Definition of a 5 MW Reference Wind Turbine for
2686	!-- offshore system developement"
2687
2688	!
2689	!-- The generator speed is filtered by a low pass filter
2690	!-- for the control of the generator torque
2691	lp_coeff = EXP( -2.0_wp * 3.14_wp * dt_3d * Fcorner )
2692	omega_gen_f(inot) = ( 1.0_wp - lp_coeff ) * omega_gen(inot) + lp_coeff *&
2693	omega_gen_f_old(inot)
2694
2695	IF ( omega_gen_f(inot) <= min_reg15 ) THEN
2696	!
2697	!-- Region 1: Generator torque is set to zero to accelerate the rotor:
2698	torque_gen(inot) = 0
2699
2700	ELSEIF ( omega_gen_f(inot) <= min_reg2 ) THEN
2701	!
2702	!-- Region 1.5: Generator torque is increasing linearly with rotor speed:
2703	torque_gen(inot) = slope15 * ( omega_gen_f(inot) - min_reg15 )
2704
2705	ELSEIF ( omega_gen_f(inot) <= min_reg25 ) THEN
2706	!
2707	!-- Region 2: Generator torque is increased by the square of the generator
2708	!-- speed to keep the TSR optimal:
2709	torque_gen(inot) = slope2 * omega_gen_f(inot) * omega_gen_f(inot)
2710
2711	ELSEIF ( omega_gen_f(inot) < rated_genspeed ) THEN
2712	!
2713	!-- Region 2.5: Slipage region between 2 and 3:
2714	torque_gen(inot) = slope25 * ( omega_gen_f(inot) - vs_sysp )
2715
2716	ELSE
2717	!
2718	!-- Region 3: Generator torque is antiproportional to the rotor speed to
2719	!-- keep the power constant:
2720	torque_gen(inot) = rated_power / omega_gen_f(inot)
2721
2722	ENDIF
2723	!
2724	!-- Calculate torque rate and confine with a max
2725	trq_rate = ( torque_gen(inot) - torque_gen_old(inot) ) / dt_3d
2726	trq_rate = MIN( MAX( trq_rate, -1.0_wp * max_trq_rate ), max_trq_rate )
2727	!
2728	!-- Calculate new gen torque and confine with max torque
2729	torque_gen(inot) = torque_gen_old(inot) + trq_rate * dt_3d
2730	torque_gen(inot) = MIN( torque_gen(inot), max_torque_gen )
2731	!
2732	!-- Overwrite values for next timestep
2733	omega_rot_l(inot) = omega_gen(inot) / gear_ratio
2734
2735
2736	END SUBROUTINE wtm_speed_control
2737
2738
2739	!------------------------------------------------------------------------------!
2740	! Description:
2741	! ------------
2742	!> Application of the additional forces generated by the wind turbine on the
2743	!> flow components (tendency terms)
2744	!> Call for all grid points
2745	!------------------------------------------------------------------------------!
2746	SUBROUTINE wtm_tendencies( component )
2747
2748
2749	IMPLICIT NONE
2750
2751	INTEGER(iwp) :: component !< prognostic variable (u,v,w)
2752	INTEGER(iwp) :: i !< running index
2753	INTEGER(iwp) :: j !< running index
2754	INTEGER(iwp) :: k !< running index
2755
2756
2757	SELECT CASE ( component )
2758
2759	CASE ( 1 )
2760	!
2761	!-- Apply the x-component of the force to the u-component of the flow:
2762	IF ( simulated_time >= time_turbine_on ) THEN
2763	DO i = nxlg, nxrg
2764	DO j = nysg, nyng
2765	DO k = nzb+1, MAXVAL(k_hub) + MAXVAL(k_smear)
2766	!
2767	!-- Calculate the thrust generated by the nacelle and the tower
2768	tend_nac_x = 0.5_wp * nac_cd_surf(k,j,i) * &
2769	SIGN( u(k,j,i)**2 , u(k,j,i) )
2770	tend_tow_x = 0.5_wp * tow_cd_surf(k,j,i) * &
2771	SIGN( u(k,j,i)**2 , u(k,j,i) )
2772
2773	tend(k,j,i) = tend(k,j,i) + ( - rot_tend_x(k,j,i) &
2774	- tend_nac_x - tend_tow_x ) &
2775	* MERGE( 1.0_wp, 0.0_wp, &
2776	BTEST( wall_flags_0(k,j,i), 1 ) )
2777	ENDDO
2778	ENDDO
2779	ENDDO
2780	ENDIF
2781
2782	CASE ( 2 )
2783	!
2784	!-- Apply the y-component of the force to the v-component of the flow:
2785	IF ( simulated_time >= time_turbine_on ) THEN
2786	DO i = nxlg, nxrg
2787	DO j = nysg, nyng
2788	DO k = nzb+1, MAXVAL(k_hub) + MAXVAL(k_smear)
2789	tend_nac_y = 0.5_wp * nac_cd_surf(k,j,i) * &
2790	SIGN( v(k,j,i)**2 , v(k,j,i) )
2791	tend_tow_y = 0.5_wp * tow_cd_surf(k,j,i) * &
2792	SIGN( v(k,j,i)**2 , v(k,j,i) )
2793	tend(k,j,i) = tend(k,j,i) + ( - rot_tend_y(k,j,i) &
2794	- tend_nac_y - tend_tow_y ) &
2795	* MERGE( 1.0_wp, 0.0_wp, &
2796	BTEST( wall_flags_0(k,j,i), 2 ) )
2797	ENDDO
2798	ENDDO
2799	ENDDO
2800	ENDIF
2801
2802	CASE ( 3 )
2803	!
2804	!-- Apply the z-component of the force to the w-component of the flow:
2805	IF ( simulated_time >= time_turbine_on ) THEN
2806	DO i = nxlg, nxrg
2807	DO j = nysg, nyng
2808	DO k = nzb+1, MAXVAL(k_hub) + MAXVAL(k_smear)
2809	tend(k,j,i) = tend(k,j,i) - rot_tend_z(k,j,i) &
2810	* MERGE( 1.0_wp, 0.0_wp, &
2811	BTEST( wall_flags_0(k,j,i), 3 ) )
2812	ENDDO
2813	ENDDO
2814	ENDDO
2815	ENDIF
2816
2817
2818	CASE DEFAULT
2819
2820	WRITE( message_string, * ) 'unknown prognostic variable: ', component
2821	CALL message( 'wtm_tendencies', 'PA04??', 1, 2, 0, 6, 0 )
2822
2823	END SELECT
2824
2825
2826	END SUBROUTINE wtm_tendencies
2827
2828
2829	!------------------------------------------------------------------------------!
2830	! Description:
2831	! ------------
2832	!> Application of the additional forces generated by the wind turbine on the
2833	!> flow components (tendency terms)
2834	!> Call for grid point i,j
2835	!------------------------------------------------------------------------------!
2836	SUBROUTINE wtm_tendencies_ij( i, j, component )
2837
2838
2839	IMPLICIT NONE
2840
2841	INTEGER(iwp) :: component !< prognostic variable (u,v,w)
2842	INTEGER(iwp) :: i !< running index
2843	INTEGER(iwp) :: j !< running index
2844	INTEGER(iwp) :: k !< running index
2845
2846	SELECT CASE ( component )
2847
2848	CASE ( 1 )
2849	!
2850	!-- Apply the x-component of the force to the u-component of the flow:
2851	IF ( simulated_time >= time_turbine_on ) THEN
2852	DO k = nzb+1, MAXVAL(k_hub) + MAXVAL(k_smear)
2853	!
2854	!-- Calculate the thrust generated by the nacelle and the tower
2855	tend_nac_x = 0.5_wp * nac_cd_surf(k,j,i) * &
2856	SIGN( u(k,j,i)**2 , u(k,j,i) )
2857	tend_tow_x = 0.5_wp * tow_cd_surf(k,j,i) * &
2858	SIGN( u(k,j,i)**2 , u(k,j,i) )
2859	tend(k,j,i) = tend(k,j,i) + ( - rot_tend_x(k,j,i) &
2860	- tend_nac_x - tend_tow_x ) &
2861	* MERGE( 1.0_wp, 0.0_wp, &
2862	BTEST( wall_flags_0(k,j,i), 1 ) )
2863	ENDDO
2864	ENDIF
2865
2866	CASE ( 2 )
2867	!
2868	!-- Apply the y-component of the force to the v-component of the flow:
2869	IF ( simulated_time >= time_turbine_on ) THEN
2870	DO k = nzb+1, MAXVAL(k_hub) + MAXVAL(k_smear)
2871	tend_nac_y = 0.5_wp * nac_cd_surf(k,j,i) * &
2872	SIGN( v(k,j,i)**2 , v(k,j,i) )
2873	tend_tow_y = 0.5_wp * tow_cd_surf(k,j,i) * &
2874	SIGN( v(k,j,i)**2 , v(k,j,i) )
2875	tend(k,j,i) = tend(k,j,i) + ( - rot_tend_y(k,j,i) &
2876	- tend_nac_y - tend_tow_y ) &
2877	* MERGE( 1.0_wp, 0.0_wp, &
2878	BTEST( wall_flags_0(k,j,i), 2 ) )
2879	ENDDO
2880	ENDIF
2881
2882	CASE ( 3 )
2883	!
2884	!-- Apply the z-component of the force to the w-component of the flow:
2885	IF ( simulated_time >= time_turbine_on ) THEN
2886	DO k = nzb+1, MAXVAL(k_hub) + MAXVAL(k_smear)
2887	tend(k,j,i) = tend(k,j,i) - rot_tend_z(k,j,i) &
2888	* MERGE( 1.0_wp, 0.0_wp, &
2889	BTEST( wall_flags_0(k,j,i), 3 ) )
2890	ENDDO
2891	ENDIF
2892
2893
2894	CASE DEFAULT
2895
2896	WRITE( message_string, * ) 'unknown prognostic variable: ', component
2897	CALL message( 'wtm_tendencies', 'PA04??', 1, 2, 0, 6, 0 )
2898
2899	END SELECT
2900
2901
2902	END SUBROUTINE wtm_tendencies_ij
2903
2904	END MODULE wind_turbine_model_mod

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