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source: palm/trunk/SOURCE/wind_turbine_model_mod.f90 @ 2327

Last change on this file since 2327 was 2323, checked in by Giersch, 7 years ago
Change unit number of file WTM_DATA
Property svn:keywords set to `Id`
File size: 109.2 KB

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1	!> @file wind_turbine_model_mod.f90
2	!------------------------------------------------------------------------------!
3	! This file is part of PALM.
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 2009-2017 Carl von Ossietzky Universitaet Oldenburg
18	! Copyright 1997-2017 Leibniz Universitaet Hannover
19	!------------------------------------------------------------------------------!
20	!
21	! Current revisions:
22	! -----------------
23	!
24	!
25	! Former revisions:
26	! -----------------
27	! $Id: wind_turbine_model_mod.f90 2323 2017-07-26 12:57:38Z maronga $
28	! Change unit number of file WTM_DATA from 201 to 90
29	!
30	! 2322 2017-07-26 08:30:28Z Giersch
31	! Bugfix of error message and assign error numbers
32	!
33	! 2257 2017-06-07 14:07:05Z witha
34	! Bugfix: turb_cl_tab and turb_cd_tab were set to zero before being allocated
35	!
36	! 2233 2017-05-30 18:08:54Z suehring
37	!
38	! 2232 2017-05-30 17:47:52Z suehring
39	! Adjustments to new topography concept
40	!
41	! 2152 2017-02-17 13:27:24Z lvollmer
42	! Bugfix in subroutine wtm_read_blade_tables
43	! Addition of a tip loss model
44	!
45	! 2015 2016-09-28 08:45:18Z lvollmer
46	! Bugfix of pitch control
47	!
48	! 2000 2016-08-20 18:09:15Z knoop
49	! Forced header and separation lines into 80 columns
50	!
51	! 1929 2016-06-09 16:25:25Z suehring
52	! Bugfix: added preprocessor directives for parallel and serial mode
53	!
54	! 1914 2016-05-26 14:44:07Z witha
55	! Initial revision
56	!
57	!
58	! Description:
59	! ------------
60	!> This module calculates the effect of wind turbines on the flow fields. The
61	!> initial version contains only the advanced actuator disk with rotation method
62	!> (ADM-R).
63	!> The wind turbines include the tower effect, can be yawed and tilted.
64	!> The wind turbine model includes controllers for rotational speed, pitch and
65	!> yaw.
66	!> Currently some specifications of the NREL 5 MW reference turbine
67	!> are hardcoded whereas most input data comes from separate files (currently
68	!> external, planned to be included as namelist which will be read in
69	!> automatically).
70	!>
71	!> @todo Revise code according to PALM Coding Standard
72	!> @todo Implement ADM and ALM turbine models
73	!> @todo Generate header information
74	!> @todo Implement further parameter checks and error messages
75	!> @todo Revise and add code documentation
76	!> @todo Output turbine parameters as timeseries
77	!> @todo Include additional output variables
78	!> @todo Revise smearing the forces for turbines in yaw
79	!> @todo Revise nacelle and tower parameterization
80	!> @todo Allow different turbine types in one simulation
81	!
82	!------------------------------------------------------------------------------!
83	MODULE wind_turbine_model_mod
84
85	USE arrays_3d, &
86	ONLY: dd2zu, tend, u, v, w, zu, zw
87
88	USE constants
89
90	USE control_parameters, &
91	ONLY: dt_3d, dz, message_string, simulated_time
92
93	USE cpulog, &
94	ONLY: cpu_log, log_point_s
95
96	USE grid_variables, &
97	ONLY: ddx, dx, ddy, dy
98
99	USE indices, &
100	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nz, &
101	nzb, nzt, wall_flags_0
102
103	USE kinds
104
105	USE pegrid
106
107
108	IMPLICIT NONE
109
110	PRIVATE
111
112	LOGICAL :: wind_turbine=.FALSE. !< switch for use of wind turbine model
113
114	!
115	!-- Variables specified in the namelist wind_turbine_par
116
117	INTEGER(iwp) :: nairfoils = 8 !< number of airfoils of the used turbine model (for ADM-R and ALM)
118	INTEGER(iwp) :: nturbines = 1 !< number of turbines
119
120	LOGICAL :: pitch_control = .FALSE. !< switch for use of pitch controller
121	LOGICAL :: speed_control = .FALSE. !< switch for use of speed controller
122	LOGICAL :: yaw_control = .FALSE. !< switch for use of yaw controller
123	LOGICAL :: tl_cor = .FALSE. !< switch for use of tip loss correct.
124
125	REAL(wp) :: segment_length = 1.0_wp !< length of the segments, the rotor area is divided into
126	!< (in tangential direction, as factor of MIN(dx,dy,dz))
127	REAL(wp) :: segment_width = 0.5_wp !< width of the segments, the rotor area is divided into
128	!< (in radial direction, as factor of MIN(dx,dy,dz))
129	REAL(wp) :: time_turbine_on = 0.0_wp !< time at which turbines are started
130	REAL(wp) :: tilt = 0.0_wp !< vertical tilt of the rotor [degree] ( positive = backwards )
131
132	REAL(wp), DIMENSION(1:100) :: dtow = 0.0_wp !< tower diameter [m]
133	REAL(wp), DIMENSION(1:100) :: omega_rot = 0.0_wp !< inital or constant rotor speed [rad/s]
134	REAL(wp), DIMENSION(1:100) :: phi_yaw = 0.0_wp !< yaw angle [degree] ( clockwise, 0 = facing west )
135	REAL(wp), DIMENSION(1:100) :: pitch_add = 0.0_wp !< constant pitch angle
136	REAL(wp), DIMENSION(1:100) :: rcx = 9999999.9_wp !< position of hub in x-direction
137	REAL(wp), DIMENSION(1:100) :: rcy = 9999999.9_wp !< position of hub in y-direction
138	REAL(wp), DIMENSION(1:100) :: rcz = 9999999.9_wp !< position of hub in z-direction
139	REAL(wp), DIMENSION(1:100) :: rnac = 0.0_wp !< nacelle diameter [m]
140	REAL(wp), DIMENSION(1:100) :: rr = 63.0_wp !< rotor radius [m]
141	REAL(wp), DIMENSION(1:100) :: turb_cd_nacelle = 0.85_wp !< drag coefficient for nacelle
142	REAL(wp), DIMENSION(1:100) :: turb_cd_tower = 1.2_wp !< drag coefficient for tower
143
144	!
145	!-- Variables specified in the namelist for speed controller
146	!-- Default values are from the NREL 5MW research turbine (Jonkman, 2008)
147
148	REAL(wp) :: rated_power = 5296610.0_wp !< rated turbine power [W]
149	REAL(wp) :: gear_ratio = 97.0_wp !< Gear ratio from rotor to generator
150	REAL(wp) :: inertia_rot = 34784179.0_wp !< Inertia of the rotor [kg/m2]
151	REAL(wp) :: inertia_gen = 534.116_wp !< Inertia of the generator [kg/m2]
152	REAL(wp) :: gen_eff = 0.944_wp !< Electric efficiency of the generator
153	REAL(wp) :: gear_eff = 1.0_wp !< Loss between rotor and generator
154	REAL(wp) :: air_dens = 1.225_wp !< Air density to convert to W [kg/m3]
155	REAL(wp) :: rated_genspeed = 121.6805_wp !< Rated generator speed [rad/s]
156	REAL(wp) :: max_torque_gen = 47402.91_wp !< Maximum of the generator torque [Nm]
157	REAL(wp) :: slope2 = 2.332287_wp !< Slope constant for region 2
158	REAL(wp) :: min_reg2 = 91.21091_wp !< Lower generator speed boundary of region 2 [rad/s]
159	REAL(wp) :: min_reg15 = 70.16224_wp !< Lower generator speed boundary of region 1.5 [rad/s]
160	REAL(wp) :: max_trq_rate = 15000.0_wp !< Max generator torque increase [Nm/s]
161	REAL(wp) :: pitch_rate = 8.0_wp !< Max pitch rate [degree/s]
162
163
164	!
165	!-- Variables specified in the namelist for yaw control
166
167	REAL(wp) :: yaw_speed = 0.005236_wp !< speed of the yaw actuator [rad/s]
168	REAL(wp) :: max_miss = 0.08726_wp !< maximum tolerated yaw missalignment [rad]
169	REAL(wp) :: min_miss = 0.008726_wp !< minimum yaw missalignment for which the actuator stops [rad]
170
171	!
172	!-- Set flag for output files TURBINE_PARAMETERS
173	TYPE file_status
174	LOGICAL :: opened, opened_before
175	END TYPE file_status
176
177	TYPE(file_status), DIMENSION(500) :: openfile_turb_mod = &
178	file_status(.FALSE.,.FALSE.)
179
180	!
181	!-- Variables for initialization of the turbine model
182
183	INTEGER(iwp) :: inot !< turbine loop index (turbine id)
184	INTEGER(iwp) :: nsegs_max !< maximum number of segments (all turbines, required for allocation of arrays)
185	INTEGER(iwp) :: nrings_max !< maximum number of rings (all turbines, required for allocation of arrays)
186	INTEGER(iwp) :: ring !< ring loop index (ring number)
187	INTEGER(iwp) :: rr_int !<
188	INTEGER(iwp) :: upper_end !<
189
190	INTEGER(iwp), DIMENSION(1) :: lct !<
191
192	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: i_hub !< index belonging to x-position of the turbine
193	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: i_smear !< index defining the area for the smearing of the forces (x-direction)
194	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: j_hub !< index belonging to y-position of the turbine
195	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: j_smear !< index defining the area for the smearing of the forces (y-direction)
196	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: k_hub !< index belonging to hub height
197	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: k_smear !< index defining the area for the smearing of the forces (z-direction)
198	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nrings !< number of rings per turbine
199	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nsegs_total !< total number of segments per turbine
200
201	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: nsegs !< number of segments per ring and turbine
202
203	!
204	!- parameters for the smearing from the rotor to the cartesian grid
205	REAL(wp) :: pol_a !< parameter for the polynomial smearing fct
206	REAL(wp) :: pol_b !< parameter for the polynomial smearing fct
207	REAL(wp) :: delta_t_factor !<
208	REAL(wp) :: eps_factor !<
209	REAL(wp) :: eps_min !<
210	REAL(wp) :: eps_min2 !<
211	REAL(wp) :: sqrt_arg !<
212
213	!
214	!-- Variables for the calculation of lift and drag coefficients
215	REAL(wp), DIMENSION(:), ALLOCATABLE :: ard !<
216	REAL(wp), DIMENSION(:), ALLOCATABLE :: crd !<
217	REAL(wp), DIMENSION(:), ALLOCATABLE :: delta_r !< radial segment length
218	REAL(wp), DIMENSION(:), ALLOCATABLE :: lrd !<
219
220	REAL(wp) :: accu_cl_cd_tab = 0.1_wp !< Accuracy of the interpolation of
221	!< the lift and drag coeff [deg]
222
223	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cd_tab !< table of the blade drag coefficient
224	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cl_tab !< table of the blade lift coefficient
225
226	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: nac_cd_surf !< 3d field of the tower drag coefficient
227	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: tow_cd_surf !< 3d field of the nacelle drag coefficient
228
229	!
230	!-- Variables for the calculation of the forces
231
232	REAL(wp) :: cur_r !<
233	REAL(wp) :: delta_t !< tangential segment length
234	REAL(wp) :: phi_rotor !<
235	REAL(wp) :: pre_factor !<
236	REAL(wp) :: torque_seg !<
237	REAL(wp) :: u_int_l !<
238	REAL(wp) :: u_int_u !<
239	REAL(wp) :: u_rot !<
240	REAL(wp) :: v_int_l !<
241	REAL(wp) :: v_int_u !<
242	REAL(wp) :: w_int_l !<
243	REAL(wp) :: w_int_u !<
244	!
245	!- Tendencies from the nacelle and tower thrust
246	REAL(wp) :: tend_nac_x = 0.0_wp !<
247	REAL(wp) :: tend_tow_x = 0.0_wp !<
248	REAL(wp) :: tend_nac_y = 0.0_wp !<
249	REAL(wp) :: tend_tow_y = 0.0_wp !<
250
251	REAL(wp), DIMENSION(:), ALLOCATABLE :: alpha_attack !<
252	REAL(wp), DIMENSION(:), ALLOCATABLE :: chord !<
253	REAL(wp), DIMENSION(:), ALLOCATABLE :: omega_gen !< curr. generator speed
254	REAL(wp), DIMENSION(:), ALLOCATABLE :: phi_rel !<
255	REAL(wp), DIMENSION(:), ALLOCATABLE :: pitch_add_old!<
256	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_total !<
257	REAL(wp), DIMENSION(:), ALLOCATABLE :: thrust_rotor !<
258	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl !<
259	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd !<
260	REAL(wp), DIMENSION(:), ALLOCATABLE :: vrel !<
261	REAL(wp), DIMENSION(:), ALLOCATABLE :: vtheta !<
262
263	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: rbx, rby, rbz !< coordinates of the blade elements
264	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: rotx, roty, rotz !< normal vectors to the rotor coordinates
265
266	!
267	!- Fields for the interpolation of velocities on the rotor grid
268	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: u_int !<
269	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: u_int_1_l !<
270	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: v_int !<
271	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: v_int_1_l !<
272	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: w_int !<
273	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: w_int_1_l !<
274
275	!
276	!- rotor tendencies on the segments
277	REAL(wp), DIMENSION(:), ALLOCATABLE :: thrust_seg !<
278	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_seg_y !<
279	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_seg_z !<
280
281	!
282	!- rotor tendencies on the rings
283	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: thrust_ring !<
284	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: torque_ring_y !<
285	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: torque_ring_z !<
286
287	!
288	!- rotor tendencies on rotor grids for all turbines
289	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: thrust !<
290	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: torque_y !<
291	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: torque_z !<
292
293	!
294	!- rotor tendencies on coordinate grid
295	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_x !<
296	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_y !<
297	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_z !<
298	!
299	!- variables for the rotation of the rotor coordinates
300	REAL(wp), DIMENSION(1:100,1:3,1:3) :: rot_coord_trans !< matrix for rotation of rotor coordinates
301
302	REAL(wp), DIMENSION(1:3) :: rot_eigen_rad !<
303	REAL(wp), DIMENSION(1:3) :: rot_eigen_azi !<
304	REAL(wp), DIMENSION(1:3) :: rot_eigen_nor !<
305	REAL(wp), DIMENSION(1:3) :: re !<
306	REAL(wp), DIMENSION(1:3) :: rea !<
307	REAL(wp), DIMENSION(1:3) :: ren !<
308	REAL(wp), DIMENSION(1:3) :: rote !<
309	REAL(wp), DIMENSION(1:3) :: rota !<
310	REAL(wp), DIMENSION(1:3) :: rotn !<
311
312	!
313	!-- Fixed variables for the speed controller
314
315	LOGICAL :: start_up = .TRUE. !<
316
317	REAL(wp) :: Fcorner !< corner freq for the controller low pass filter
318	REAL(wp) :: min_reg25 !< min region 2.5
319	REAL(wp) :: om_rate !< rotor speed change
320	REAL(wp) :: slope15 !< slope in region 1.5
321	REAL(wp) :: slope25 !< slope in region 2.5
322	REAL(wp) :: trq_rate !< torque change
323	REAL(wp) :: vs_sysp !<
324	REAL(wp) :: lp_coeff !< coeff for the controller low pass filter
325
326	REAL(wp), DIMENSION(:), ALLOCATABLE :: omega_gen_old !< last gen. speed
327	REAL(wp), DIMENSION(:), ALLOCATABLE :: omega_gen_f !< filtered gen. sp
328	REAL(wp), DIMENSION(:), ALLOCATABLE :: omega_gen_f_old !< last filt. gen. sp
329	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_gen !< generator torque
330	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_gen_old !< last gen. torque
331
332	REAL(wp), DIMENSION(100) :: omega_rot_l = 0.0_wp !< local rot speed [rad/s]
333	!
334	!-- Fixed variables for the yaw controller
335
336	REAL(wp), DIMENSION(:) , ALLOCATABLE :: yawdir !< direction to yaw
337	REAL(wp), DIMENSION(:) , ALLOCATABLE :: phi_yaw_l !< local (cpu) yaw angle
338	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wd30_l !< local (cpu) long running avg of the wd
339	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wd2_l !< local (cpu) short running avg of the wd
340	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wdir !< wind direction at hub
341	REAL(wp), DIMENSION(:) , ALLOCATABLE :: u_inflow !< wind speed at hub
342	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wdir_l !<
343	REAL(wp), DIMENSION(:) , ALLOCATABLE :: u_inflow_l !<
344	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: wd30 !<
345	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: wd2 !<
346	LOGICAL, DIMENSION(1:100) :: doyaw = .FALSE. !<
347	INTEGER(iwp) :: WDLON !<
348	INTEGER(iwp) :: WDSHO !<
349
350
351	SAVE
352
353
354	INTERFACE wtm_parin
355	MODULE PROCEDURE wtm_parin
356	END INTERFACE wtm_parin
357
358	INTERFACE wtm_check_parameters
359	MODULE PROCEDURE wtm_check_parameters
360	END INTERFACE wtm_check_parameters
361
362	INTERFACE wtm_init_arrays
363	MODULE PROCEDURE wtm_init_arrays
364	END INTERFACE wtm_init_arrays
365
366	INTERFACE wtm_init
367	MODULE PROCEDURE wtm_init
368	END INTERFACE wtm_init
369
370	INTERFACE wtm_read_blade_tables
371	MODULE PROCEDURE wtm_read_blade_tables
372	END INTERFACE wtm_read_blade_tables
373
374	INTERFACE wtm_forces
375	MODULE PROCEDURE wtm_forces
376	MODULE PROCEDURE wtm_yawcontrol
377	END INTERFACE wtm_forces
378
379	INTERFACE wtm_rotate_rotor
380	MODULE PROCEDURE wtm_rotate_rotor
381	END INTERFACE wtm_rotate_rotor
382
383	INTERFACE wtm_speed_control
384	MODULE PROCEDURE wtm_init_speed_control
385	MODULE PROCEDURE wtm_speed_control
386	END INTERFACE wtm_speed_control
387
388	INTERFACE wtm_tendencies
389	MODULE PROCEDURE wtm_tendencies
390	MODULE PROCEDURE wtm_tendencies_ij
391	END INTERFACE wtm_tendencies
392
393
394	PUBLIC wtm_check_parameters, wtm_forces, wtm_init, wtm_init_arrays, &
395	wtm_parin, wtm_tendencies, wtm_tendencies_ij, wind_turbine
396
397	CONTAINS
398
399
400	!------------------------------------------------------------------------------!
401	! Description:
402	! ------------
403	!> Parin for &wind_turbine_par for wind turbine model
404	!------------------------------------------------------------------------------!
405	SUBROUTINE wtm_parin
406
407
408	IMPLICIT NONE
409
410	INTEGER(iwp) :: ierrn !<
411
412	CHARACTER (LEN=80) :: line !< dummy string that contains the current line of the parameter file
413
414	NAMELIST /wind_turbine_par/ air_dens, dtow, gear_eff, gear_ratio, &
415	gen_eff, inertia_gen, inertia_rot, max_miss, &
416	max_torque_gen, max_trq_rate, min_miss, &
417	min_reg15, min_reg2, nairfoils, nturbines, &
418	omega_rot, phi_yaw, pitch_add, pitch_control,&
419	rated_genspeed, rated_power, rcx, rcy, rcz, &
420	rnac, rr, segment_length, segment_width, &
421	slope2, speed_control, tilt, time_turbine_on,&
422	turb_cd_nacelle, turb_cd_tower, &
423	yaw_control, yaw_speed, tl_cor
424
425	!
426	!-- Try to find wind turbine model package
427	REWIND ( 11 )
428	line = ' '
429	DO WHILE ( INDEX( line, '&wind_turbine_par' ) == 0 )
430	READ ( 11, '(A)', END=10 ) line
431	ENDDO
432	BACKSPACE ( 11 )
433
434	!
435	!-- Read user-defined namelist
436	READ ( 11, wind_turbine_par, IOSTAT=ierrn )
437
438	IF ( ierrn < 0 ) THEN
439	message_string = 'errors in \$wind_turbine_par'
440	CALL message( 'wtm_parin', 'PA0460', 1, 2, 0, 6, 0 )
441	ENDIF
442
443	!
444	!-- Set flag that indicates that the wind turbine model is switched on
445	wind_turbine = .TRUE.
446
447	10 CONTINUE ! TBD Change from continue, mit ierrn machen
448
449
450	END SUBROUTINE wtm_parin
451
452	SUBROUTINE wtm_check_parameters
453
454
455	IMPLICIT NONE
456
457	IF ( ( .NOT.speed_control ) .AND. pitch_control ) THEN
458	message_string = 'pitch_control = .TRUE. requires '// &
459	'speed_control = .TRUE.'
460	CALL message( 'wtm_check_parameters', 'PA0461', 1, 2, 0, 6, 0 )
461	ENDIF
462
463	IF ( ANY( omega_rot(1:nturbines) < 0.0 ) ) THEN
464	message_string = 'omega_rot < 0.0, Please set omega_rot to ' // &
465	'a value larger than zero'
466	CALL message( 'wtm_check_parameters', 'PA0462', 1, 2, 0, 6, 0 )
467	ENDIF
468
469
470	IF ( ANY( rcx(1:nturbines) == 9999999.9_wp ) .OR. &
471	ANY( rcy(1:nturbines) == 9999999.9_wp ) .OR. &
472	ANY( rcz(1:nturbines) == 9999999.9_wp ) ) THEN
473
474	message_string = 'rcx, rcy, rcz ' // &
475	'have to be given for each turbine.'
476	CALL message( 'wtm_check_parameters', 'PA0463', 1, 2, 0, 6, 0 )
477
478	ENDIF
479
480
481	END SUBROUTINE wtm_check_parameters
482
483
484	!------------------------------------------------------------------------------!
485	! Description:
486	! ------------
487	!> Allocate wind turbine model arrays
488	!------------------------------------------------------------------------------!
489	SUBROUTINE wtm_init_arrays
490
491
492	IMPLICIT NONE
493
494	REAL(wp) :: delta_r_factor !<
495	REAL(wp) :: delta_r_init !<
496
497	!
498	!-- To be able to allocate arrays with dimension of rotor rings and segments,
499	!-- the maximum possible numbers of rings and segments have to be calculated:
500
501	ALLOCATE( nrings(1:nturbines) )
502	ALLOCATE( delta_r(1:nturbines) )
503
504	nrings(:) = 0
505	delta_r(:) = 0.0_wp
506
507	!
508	!-- Thickness (radial) of each ring and length (tangential) of each segment:
509	delta_r_factor = segment_width
510	delta_t_factor = segment_length
511	delta_r_init = delta_r_factor * MIN( dx, dy, dz)
512	delta_t = delta_t_factor * MIN( dx, dy, dz)
513
514	DO inot = 1, nturbines
515	!
516	!-- Determine number of rings:
517	nrings(inot) = NINT( rr(inot) / delta_r_init )
518
519	delta_r(inot) = rr(inot) / nrings(inot)
520
521	ENDDO
522
523	nrings_max = MAXVAL(nrings)
524
525	ALLOCATE( nsegs(1:nrings_max,1:nturbines) )
526	ALLOCATE( nsegs_total(1:nturbines) )
527
528	nsegs(:,:) = 0
529	nsegs_total(:) = 0
530
531
532	DO inot = 1, nturbines
533	DO ring = 1, nrings(inot)
534	!
535	!-- Determine number of segments for each ring:
536	nsegs(ring,inot) = MAX( 8, CEILING( delta_r_factor * pi * &
537	( 2.0_wp * ring - 1.0_wp ) / &
538	delta_t_factor ) )
539	ENDDO
540	!
541	!-- Total sum of all rotor segments:
542	nsegs_total(inot) = SUM( nsegs(:,inot) )
543
544	ENDDO
545
546	!
547	!-- Maximum number of segments per ring:
548	nsegs_max = MAXVAL(nsegs)
549
550	!!
551	!!-- TODO: Folgendes im Header ausgeben!
552	! IF ( myid == 0 ) THEN
553	! PRINT*, 'nrings(1) = ', nrings(1)
554	! PRINT*, '--------------------------------------------------'
555	! PRINT*, 'nsegs(:,1) = ', nsegs(:,1)
556	! PRINT*, '--------------------------------------------------'
557	! PRINT*, 'nrings_max = ', nrings_max
558	! PRINT*, 'nsegs_max = ', nsegs_max
559	! PRINT*, 'nsegs_total(1) = ', nsegs_total(1)
560	! ENDIF
561
562
563	!
564	!-- Allocate 1D arrays (dimension = number of turbines)
565	ALLOCATE( i_hub(1:nturbines) )
566	ALLOCATE( i_smear(1:nturbines) )
567	ALLOCATE( j_hub(1:nturbines) )
568	ALLOCATE( j_smear(1:nturbines) )
569	ALLOCATE( k_hub(1:nturbines) )
570	ALLOCATE( k_smear(1:nturbines) )
571	ALLOCATE( torque_total(1:nturbines) )
572	ALLOCATE( thrust_rotor(1:nturbines) )
573
574	!
575	!-- Allocation of the 1D arrays for speed pitch_control
576	ALLOCATE( omega_gen(1:nturbines) )
577	ALLOCATE( omega_gen_old(1:nturbines) )
578	ALLOCATE( omega_gen_f(1:nturbines) )
579	ALLOCATE( omega_gen_f_old(1:nturbines) )
580	ALLOCATE( pitch_add_old(1:nturbines) )
581	ALLOCATE( torque_gen(1:nturbines) )
582	ALLOCATE( torque_gen_old(1:nturbines) )
583
584	!
585	!-- Allocation of the 1D arrays for yaw control
586	ALLOCATE( yawdir(1:nturbines) )
587	ALLOCATE( u_inflow(1:nturbines) )
588	ALLOCATE( wdir(1:nturbines) )
589	ALLOCATE( u_inflow_l(1:nturbines) )
590	ALLOCATE( wdir_l(1:nturbines) )
591	ALLOCATE( phi_yaw_l(1:nturbines) )
592
593	!
594	!-- Allocate 1D arrays (dimension = number of rotor segments)
595	ALLOCATE( alpha_attack(1:nsegs_max) )
596	ALLOCATE( chord(1:nsegs_max) )
597	ALLOCATE( phi_rel(1:nsegs_max) )
598	ALLOCATE( thrust_seg(1:nsegs_max) )
599	ALLOCATE( torque_seg_y(1:nsegs_max) )
600	ALLOCATE( torque_seg_z(1:nsegs_max) )
601	ALLOCATE( turb_cd(1:nsegs_max) )
602	ALLOCATE( turb_cl(1:nsegs_max) )
603	ALLOCATE( vrel(1:nsegs_max) )
604	ALLOCATE( vtheta(1:nsegs_max) )
605
606	!
607	!-- Allocate 2D arrays (dimension = number of rotor rings and segments)
608	ALLOCATE( rbx(1:nrings_max,1:nsegs_max) )
609	ALLOCATE( rby(1:nrings_max,1:nsegs_max) )
610	ALLOCATE( rbz(1:nrings_max,1:nsegs_max) )
611	ALLOCATE( thrust_ring(1:nrings_max,1:nsegs_max) )
612	ALLOCATE( torque_ring_y(1:nrings_max,1:nsegs_max) )
613	ALLOCATE( torque_ring_z(1:nrings_max,1:nsegs_max) )
614
615	!
616	!-- Allocate additional 2D arrays
617	ALLOCATE( rotx(1:nturbines,1:3) )
618	ALLOCATE( roty(1:nturbines,1:3) )
619	ALLOCATE( rotz(1:nturbines,1:3) )
620
621	!
622	!-- Allocate 3D arrays (dimension = number of grid points)
623	ALLOCATE( nac_cd_surf(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
624	ALLOCATE( rot_tend_x(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
625	ALLOCATE( rot_tend_y(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
626	ALLOCATE( rot_tend_z(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
627	ALLOCATE( thrust(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
628	ALLOCATE( torque_y(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
629	ALLOCATE( torque_z(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
630	ALLOCATE( tow_cd_surf(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
631
632	!
633	!-- Allocate additional 3D arrays
634	ALLOCATE( u_int(1:nturbines,1:nrings_max,1:nsegs_max) )
635	ALLOCATE( u_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) )
636	ALLOCATE( v_int(1:nturbines,1:nrings_max,1:nsegs_max) )
637	ALLOCATE( v_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) )
638	ALLOCATE( w_int(1:nturbines,1:nrings_max,1:nsegs_max) )
639	ALLOCATE( w_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) )
640
641	!
642	!-- All of the arrays are initialized with a value of zero:
643	i_hub(:) = 0
644	i_smear(:) = 0
645	j_hub(:) = 0
646	j_smear(:) = 0
647	k_hub(:) = 0
648	k_smear(:) = 0
649
650	torque_total(:) = 0.0_wp
651	thrust_rotor(:) = 0.0_wp
652
653	omega_gen(:) = 0.0_wp
654	omega_gen_old(:) = 0.0_wp
655	omega_gen_f(:) = 0.0_wp
656	omega_gen_f_old(:) = 0.0_wp
657	pitch_add_old(:) = 0.0_wp
658	torque_gen(:) = 0.0_wp
659	torque_gen_old(:) = 0.0_wp
660
661	yawdir(:) = 0.0_wp
662	wdir(:) = 0.0_wp
663	u_inflow(:) = 0.0_wp
664
665	!
666	!-- Allocate 1D arrays (dimension = number of rotor segments)
667	alpha_attack(:) = 0.0_wp
668	chord(:) = 0.0_wp
669	phi_rel(:) = 0.0_wp
670	thrust_seg(:) = 0.0_wp
671	torque_seg_y(:) = 0.0_wp
672	torque_seg_z(:) = 0.0_wp
673	turb_cd(:) = 0.0_wp
674	turb_cl(:) = 0.0_wp
675	vrel(:) = 0.0_wp
676	vtheta(:) = 0.0_wp
677
678	rbx(:,:) = 0.0_wp
679	rby(:,:) = 0.0_wp
680	rbz(:,:) = 0.0_wp
681	thrust_ring(:,:) = 0.0_wp
682	torque_ring_y(:,:) = 0.0_wp
683	torque_ring_z(:,:) = 0.0_wp
684
685	rotx(:,:) = 0.0_wp
686	roty(:,:) = 0.0_wp
687	rotz(:,:) = 0.0_wp
688
689	nac_cd_surf(:,:,:) = 0.0_wp
690	rot_tend_x(:,:,:) = 0.0_wp
691	rot_tend_y(:,:,:) = 0.0_wp
692	rot_tend_z(:,:,:) = 0.0_wp
693	thrust(:,:,:) = 0.0_wp
694	torque_y(:,:,:) = 0.0_wp
695	torque_z(:,:,:) = 0.0_wp
696	tow_cd_surf(:,:,:) = 0.0_wp
697
698	u_int(:,:,:) = 0.0_wp
699	u_int_1_l(:,:,:) = 0.0_wp
700	v_int(:,:,:) = 0.0_wp
701	v_int_1_l(:,:,:) = 0.0_wp
702	w_int(:,:,:) = 0.0_wp
703	w_int_1_l(:,:,:) = 0.0_wp
704
705
706	END SUBROUTINE wtm_init_arrays
707
708
709	!------------------------------------------------------------------------------!
710	! Description:
711	! ------------
712	!> Initialization of the wind turbine model
713	!------------------------------------------------------------------------------!
714	SUBROUTINE wtm_init
715
716
717	IMPLICIT NONE
718
719	INTEGER(iwp) :: i !< running index
720	INTEGER(iwp) :: j !< running index
721	INTEGER(iwp) :: k !< running index
722
723	!
724	!-- Help variables for the smearing function
725	REAL(wp) :: eps_kernel !<
726
727	!
728	!-- Help variables for calculation of the tower drag
729	INTEGER(iwp) :: tower_n !<
730	INTEGER(iwp) :: tower_s !<
731	!
732	!-- Help variables for the calulaction of the nacelle drag
733	INTEGER(iwp) :: i_ip !<
734	INTEGER(iwp) :: i_ipg !<
735
736	REAL(wp) :: yvalue
737	REAL(wp) :: dy_int !<
738	REAL(wp) :: dz_int !<
739
740	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: circle_points !<
741
742	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nacb !<
743	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nacl !<
744	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nacr !<
745	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nact !<
746
747	ALLOCATE( index_nacb(1:nturbines) )
748	ALLOCATE( index_nacl(1:nturbines) )
749	ALLOCATE( index_nacr(1:nturbines) )
750	ALLOCATE( index_nact(1:nturbines) )
751
752
753	IF ( speed_control) THEN
754
755	CALL wtm_speed_control
756
757	ENDIF
758
759	!
760	!------------------------------------------------------------------------------!
761	!-- Calculation of parameters for the regularization kernel
762	!-- (smearing of the forces)
763	!------------------------------------------------------------------------------!
764	!
765	!-- In the following, some of the required parameters for the smearing will
766	!-- be calculated:
767
768	!-- The kernel is set equal to twice the grid spacing which has turned out to
769	!-- be a reasonable value (see e.g. Troldborg et al. (2013), Wind Energy,
770	!-- DOI: 10.1002/we.1608):
771	eps_kernel = 2.0_wp * dx
772	!
773	!-- The zero point (eps_min) of the polynomial function must be the following
774	!-- if the integral of the polynomial function (for values < eps_min) shall
775	!-- be equal to the integral of the Gaussian function used before:
776	eps_min = ( 105.0_wp / 32.0_wp )*( 1.0_wp / 3.0_wp ) &
777	pi*( 1.0_wp / 6.0_wp ) eps_kernel
778	!
779	!-- Square of eps_min:
780	eps_min2 = eps_min**2
781	!
782	!-- Parameters in the polynomial function:
783	pol_a = 1.0_wp / eps_min**4
784	pol_b = 2.0_wp / eps_min**2
785	!
786	!-- Normalization factor which is the inverse of the integral of the smearing
787	!-- function:
788	eps_factor = 105.0_wp / ( 32.0_wp * pi * eps_min**3 )
789
790	!-- Change tilt angle to rad:
791	tilt = tilt * pi / 180.0_wp
792
793	!
794	!-- Change yaw angle to rad:
795	phi_yaw(:) = phi_yaw(:) * pi / 180.0_wp
796
797
798	DO inot = 1, nturbines
799	!
800	!-- Rotate the rotor coordinates in case yaw and tilt are defined
801	CALL wtm_rotate_rotor( inot )
802
803	!
804	!-- Determine the indices of the hub height
805	i_hub(inot) = INT( rcx(inot) / dx )
806	j_hub(inot) = INT( ( rcy(inot) + 0.5_wp * dy ) / dy )
807	k_hub(inot) = INT( ( rcz(inot) + 0.5_wp * dz ) / dz )
808
809	!
810	!-- Determining the area to which the smearing of the forces is applied.
811	!-- As smearing now is effectively applied only for distances smaller than
812	!-- eps_min, the smearing area can be further limited and regarded as a
813	!-- function of eps_min:
814	i_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dx )
815	j_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dy )
816	k_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dz )
817
818	ENDDO
819
820	!
821	!------------------------------------------------------------------------------!
822	!-- Determine the area within each grid cell that overlaps with the area
823	!-- of the nacelle and the tower (needed for calculation of the forces)
824	!------------------------------------------------------------------------------!
825	!
826	!-- Note: so far this is only a 2D version, in that the mean flow is
827	!-- perpendicular to the rotor area.
828
829	!
830	!-- Allocation of the array containing information on the intersection points
831	!-- between rotor disk and the numerical grid:
832	upper_end = ( ny + 1 ) * 10000
833
834	ALLOCATE( circle_points(1:2,1:upper_end) )
835
836	circle_points(:,:) = 0.0_wp
837
838
839	DO inot = 1, nturbines ! loop over number of turbines
840	!
841	!-- Determine the grid index (u-grid) that corresponds to the location of
842	!-- the rotor center (reduces the amount of calculations in the case that
843	!-- the mean flow is perpendicular to the rotor area):
844	i = i_hub(inot)
845
846	!
847	!-- Determine the left and the right edge of the nacelle (corresponding
848	!-- grid point indices):
849	index_nacl(inot) = INT( ( rcy(inot) - rnac(inot) + 0.5_wp * dy ) / dy )
850	index_nacr(inot) = INT( ( rcy(inot) + rnac(inot) + 0.5_wp * dy ) / dy )
851	!
852	!-- Determine the bottom and the top edge of the nacelle (corresponding
853	!-- grid point indices).The grid point index has to be increased by 1, as
854	!-- the first level for the u-component (index 0) is situated below the
855	!-- surface. All points between z=0 and z=dz/s would already be contained
856	!-- in grid box 1.
857	index_nacb(inot) = INT( ( rcz(inot) - rnac(inot) ) / dz ) + 1
858	index_nact(inot) = INT( ( rcz(inot) + rnac(inot) ) / dz ) + 1
859
860	!
861	!-- Determine the indices of the grid boxes containing the left and
862	!-- the right boundaries of the tower:
863	tower_n = ( rcy(inot) + 0.5_wp * dtow(inot) - 0.5_wp * dy ) / dy
864	tower_s = ( rcy(inot) - 0.5_wp * dtow(inot) - 0.5_wp * dy ) / dy
865
866	!
867	!-- Determine the fraction of the grid box area overlapping with the tower
868	!-- area and multiply it with the drag of the tower:
869	IF ( ( nxlg <= i ) .AND. ( nxrg >= i ) ) THEN
870
871	DO j = nys, nyn
872	!
873	!-- Loop from south to north boundary of tower
874	IF ( ( j >= tower_s ) .AND. ( j <= tower_n ) ) THEN
875
876	DO k = nzb, nzt
877
878	IF ( k == k_hub(inot) ) THEN
879	IF ( tower_n - tower_s >= 1 ) THEN
880	!
881	!-- leftmost and rightmost grid box:
882	IF ( j == tower_s ) THEN
883	tow_cd_surf(k,j,i) = ( rcz(inot) - &
884	( k_hub(inot) * dz - 0.5_wp * dz ) ) * & ! extension in z-direction
885	( ( tower_s + 1.0_wp + 0.5_wp ) * dy - &
886	( rcy(inot) - 0.5_wp * dtow(inot) ) ) * & ! extension in y-direction
887	turb_cd_tower(inot)
888	ELSEIF ( j == tower_n ) THEN
889	tow_cd_surf(k,j,i) = ( rcz(inot) - &
890	( k_hub(inot) * dz - 0.5_wp * dz ) ) * & ! extension in z-direction
891	( ( rcy(inot) + 0.5_wp * dtow(inot) ) - &
892	( tower_n + 0.5_wp ) * dy ) * & ! extension in y-direction
893	turb_cd_tower(inot)
894	!
895	!-- grid boxes inbetween
896	!-- (where tow_cd_surf = grid box area):
897	ELSE
898	tow_cd_surf(k,j,i) = ( rcz(inot) - &
899	( k_hub(inot) * dz - 0.5_wp * dz ) ) * &
900	dy * turb_cd_tower(inot)
901	ENDIF
902	!
903	!-- tower lies completely within one grid box:
904	ELSE
905	tow_cd_surf(k,j,i) = ( rcz(inot) - &
906	( k_hub(inot) * dz - 0.5_wp * dz ) ) * &
907	dtow(inot) * turb_cd_tower(inot)
908	ENDIF
909	!
910	!-- In case that k is smaller than k_hub the following actions
911	!-- are carried out:
912	ELSEIF ( k < k_hub(inot) ) THEN
913
914	IF ( ( tower_n - tower_s ) >= 1 ) THEN
915	!
916	!-- leftmost and rightmost grid box:
917	IF ( j == tower_s ) THEN
918	tow_cd_surf(k,j,i) = dz * ( &
919	( tower_s + 1 + 0.5_wp ) * dy - &
920	( rcy(inot) - 0.5_wp * dtow(inot) ) &
921	) * turb_cd_tower(inot)
922	ELSEIF ( j == tower_n ) THEN
923	tow_cd_surf(k,j,i) = dz * ( &
924	( rcy(inot) + 0.5_wp * dtow(inot) ) - &
925	( tower_n + 0.5_wp ) * dy &
926	) * turb_cd_tower(inot)
927	!
928	!-- grid boxes inbetween
929	!-- (where tow_cd_surf = grid box area):
930	ELSE
931	tow_cd_surf(k,j,i) = dz * dy * turb_cd_tower(inot)
932	ENDIF
933	!
934	!-- tower lies completely within one grid box:
935	ELSE
936	tow_cd_surf(k,j,i) = dz * dtow(inot) * &
937	turb_cd_tower(inot)
938	ENDIF ! end if larger than grid box
939
940	ENDIF ! end if k == k_hub
941
942	ENDDO ! end loop over k
943
944	ENDIF ! end if inside north and south boundary of tower
945
946	ENDDO ! end loop over j
947
948	ENDIF ! end if hub inside domain + ghostpoints
949
950
951	CALL exchange_horiz( tow_cd_surf, nbgp )
952
953	!
954	!-- Calculation of the nacelle area
955	!-- CAUTION: Currently disabled due to segmentation faults on the FLOW HPC
956	!-- cluster (Oldenburg)
957	!!
958	!!-- Tabulate the points on the circle that are required in the following for
959	!!-- the calculation of the Riemann integral (node points; they are called
960	!!-- circle_points in the following):
961	!
962	! dy_int = dy / 10000.0_wp
963	!
964	! DO i_ip = 1, upper_end
965	! yvalue = dy_int * ( i_ip - 0.5_wp ) + 0.5_wp * dy !<--- segmentation fault
966	! sqrt_arg = rnac(inot)2 - ( yvalue - rcy(inot) )2 !<--- segmentation fault
967	! IF ( sqrt_arg >= 0.0_wp ) THEN
968	!!
969	!!-- bottom intersection point
970	! circle_points(1,i_ip) = rcz(inot) - SQRT( sqrt_arg )
971	!!
972	!!-- top intersection point
973	! circle_points(2,i_ip) = rcz(inot) + SQRT( sqrt_arg ) !<--- segmentation fault
974	! ELSE
975	! circle_points(:,i_ip) = -111111 !<--- segmentation fault
976	! ENDIF
977	! ENDDO
978	!
979	!
980	! DO j = nys, nyn
981	!!
982	!!-- In case that the grid box is located completely outside the nacelle
983	!!-- (y) it can automatically be stated that there is no overlap between
984	!!-- the grid box and the nacelle and consequently we can set
985	!!-- nac_cd_surf(:,j,i) = 0.0:
986	! IF ( ( j >= index_nacl(inot) ) .AND. ( j <= index_nacr(inot) ) ) THEN
987	! DO k = nzb+1, nzt
988	!!
989	!!-- In case that the grid box is located completely outside the
990	!!-- nacelle (z) it can automatically be stated that there is no
991	!!-- overlap between the grid box and the nacelle and consequently
992	!!-- we can set nac_cd_surf(k,j,i) = 0.0:
993	! IF ( ( k >= index_nacb(inot) ) .OR. &
994	! ( k <= index_nact(inot) ) ) THEN
995	!!
996	!!-- For all other cases Riemann integrals are calculated.
997	!!-- Here, the points on the circle that have been determined
998	!!-- above are used in order to calculate the overlap between the
999	!!-- gridbox and the nacelle area (area approached by 10000
1000	!!-- rectangulars dz_int * dy_int):
1001	! DO i_ipg = 1, 10000
1002	! dz_int = dz
1003	! i_ip = j * 10000 + i_ipg
1004	!!
1005	!!-- Determine the vertical extension dz_int of the circle
1006	!!-- within the current grid box:
1007	! IF ( ( circle_points(2,i_ip) < zw(k) ) .AND. & !<--- segmentation fault
1008	! ( circle_points(2,i_ip) >= zw(k-1) ) ) THEN
1009	! dz_int = dz_int - & !<--- segmentation fault
1010	! ( zw(k) - circle_points(2,i_ip) )
1011	! ENDIF
1012	! IF ( ( circle_points(1,i_ip) <= zw(k) ) .AND. & !<--- segmentation fault
1013	! ( circle_points(1,i_ip) > zw(k-1) ) ) THEN
1014	! dz_int = dz_int - &
1015	! ( circle_points(1,i_ip) - zw(k-1) )
1016	! ENDIF
1017	! IF ( zw(k-1) > circle_points(2,i_ip) ) THEN
1018	! dz_int = 0.0_wp
1019	! ENDIF
1020	! IF ( zw(k) < circle_points(1,i_ip) ) THEN
1021	! dz_int = 0.0_wp
1022	! ENDIF
1023	! IF ( ( nxlg <= i ) .AND. ( nxrg >= i ) ) THEN
1024	! nac_cd_surf(k,j,i) = nac_cd_surf(k,j,i) + & !<--- segmentation fault
1025	! dy_int * dz_int * turb_cd_nacelle(inot)
1026	! ENDIF
1027	! ENDDO
1028	! ENDIF
1029	! ENDDO
1030	! ENDIF
1031	!
1032	! ENDDO
1033	!
1034	! CALL exchange_horiz( nac_cd_surf, nbgp ) !<--- segmentation fault
1035
1036	ENDDO ! end of loop over turbines
1037
1038	tow_cd_surf = tow_cd_surf / ( dx * dy * dz ) ! Normalize tower drag
1039	nac_cd_surf = nac_cd_surf / ( dx * dy * dz ) ! Normalize nacelle drag
1040
1041	CALL wtm_read_blade_tables
1042
1043	END SUBROUTINE wtm_init
1044
1045
1046	!------------------------------------------------------------------------------!
1047	! Description:
1048	! ------------
1049	!> Read in layout of the rotor blade , the lift and drag tables
1050	!> and the distribution of lift and drag tables along the blade
1051	!------------------------------------------------------------------------------!
1052	!
1053	SUBROUTINE wtm_read_blade_tables
1054
1055
1056	IMPLICIT NONE
1057
1058	INTEGER(iwp) :: ii !< running index
1059	INTEGER(iwp) :: jj !< running index
1060
1061	INTEGER(iwp) :: ierrn !<
1062
1063	CHARACTER(200) :: chmess !< Read in string
1064
1065	INTEGER(iwp) :: dlen !< no. rows of local table
1066	INTEGER(iwp) :: dlenbl !< no. rows of cd, cl table
1067	INTEGER(iwp) :: ialpha !< table position of current alpha value
1068	INTEGER(iwp) :: iialpha !<
1069	INTEGER(iwp) :: iir !<
1070	INTEGER(iwp) :: radres !< radial resolution
1071	INTEGER(iwp) :: t1 !< no. of airfoil
1072	INTEGER(iwp) :: t2 !< no. of airfoil
1073	INTEGER(iwp) :: trow !<
1074	INTEGER(iwp) :: dlenbl_int !< no. rows of interpolated cd, cl tables
1075
1076	REAL(wp) :: alpha_attack_i !<
1077	REAL(wp) :: weight_a !<
1078	REAL(wp) :: weight_b !<
1079
1080	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: ttoint1 !<
1081	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: ttoint2 !<
1082
1083	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd_sel1 !<
1084	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd_sel2 !<
1085	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl_sel1 !<
1086	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl_sel2 !<
1087	REAL(wp), DIMENSION(:), ALLOCATABLE :: read_cl_cd !< read in var array
1088
1089	REAL(wp), DIMENSION(:), ALLOCATABLE :: alpha_attack_tab !<
1090	REAL(wp), DIMENSION(:), ALLOCATABLE :: trad1 !<
1091	REAL(wp), DIMENSION(:), ALLOCATABLE :: trad2 !<
1092	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cd_table !<
1093	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cl_table !<
1094
1095	ALLOCATE ( read_cl_cd(1:2*nairfoils+1) )
1096
1097	!
1098	!-- Read in the distribution of lift and drag tables along the blade, the
1099	!-- layout of the rotor blade and the lift and drag tables:
1100
1101	OPEN ( 90, FILE='WTM_DATA', STATUS='OLD', FORM='FORMATTED', IOSTAT=ierrn )
1102
1103	IF ( ierrn /= 0 ) THEN
1104	message_string = 'file WTM_DATA does not exist'
1105	CALL message( 'wtm_init', 'PA0464', 1, 2, 0, 6, 0 )
1106	ENDIF
1107	!
1108	!-- Read distribution table:
1109
1110	dlen = 0
1111
1112	READ ( 90, '(3/)' )
1113
1114	rloop3: DO
1115	READ ( 90, *, IOSTAT=ierrn ) chmess
1116	IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop3
1117	dlen = dlen + 1
1118	ENDDO rloop3
1119
1120	ALLOCATE( trad1(1:dlen), trad2(1:dlen), ttoint1(1:dlen), ttoint2(1:dlen))
1121
1122	DO jj = 1,dlen+1
1123	BACKSPACE ( 90, IOSTAT=ierrn )
1124	ENDDO
1125
1126	DO jj = 1,dlen
1127	READ ( 90, * ) trad1(jj), trad2(jj), ttoint1(jj), ttoint2(jj)
1128	ENDDO
1129
1130	!
1131	!-- Read layout table:
1132
1133	dlen = 0
1134
1135	READ ( 90, '(3/)')
1136
1137	rloop1: DO
1138	READ ( 90, *, IOSTAT=ierrn ) chmess
1139	IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop1
1140	dlen = dlen + 1
1141	ENDDO rloop1
1142
1143	ALLOCATE( lrd(1:dlen), ard(1:dlen), crd(1:dlen) )
1144	DO jj = 1, dlen+1
1145	BACKSPACE ( 90, IOSTAT=ierrn )
1146	ENDDO
1147	DO jj = 1, dlen
1148	READ ( 90, * ) lrd(jj), ard(jj), crd(jj)
1149	ENDDO
1150
1151	!
1152	!-- Read tables (turb_cl(alpha),turb_cd(alpha) for the different profiles:
1153
1154	dlen = 0
1155
1156	READ ( 90, '(3/)' )
1157
1158	rloop2: DO
1159	READ ( 90, *, IOSTAT=ierrn ) chmess
1160	IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop2
1161	dlen = dlen + 1
1162	ENDDO rloop2
1163
1164	ALLOCATE( alpha_attack_tab(1:dlen), turb_cl_table(1:dlen,1:nairfoils), &
1165	turb_cd_table(1:dlen,1:nairfoils) )
1166
1167	DO jj = 1,dlen+1
1168	BACKSPACE ( 90, IOSTAT=ierrn )
1169	ENDDO
1170
1171	DO jj = 1,dlen
1172	READ ( 90, * ) read_cl_cd
1173	alpha_attack_tab(jj) = read_cl_cd(1)
1174	DO ii= 1, nairfoils
1175	turb_cl_table(jj,ii) = read_cl_cd(ii*2)
1176	turb_cd_table(jj,ii) = read_cl_cd(ii*2+1)
1177	ENDDO
1178
1179	ENDDO
1180
1181	dlenbl = dlen
1182
1183	CLOSE ( 90 )
1184
1185	!
1186	!-- For each possible radial position (resolution: 0.1 m --> 630 values) and
1187	!-- each possible angle of attack (resolution: 0.01 degrees --> 36000 values!)
1188	!-- determine the lift and drag coefficient by interpolating between the
1189	!-- tabulated values of each table (interpolate to current angle of attack)
1190	!-- and between the tables (interpolate to current radial position):
1191
1192	ALLOCATE( turb_cl_sel1(0:dlenbl) )
1193	ALLOCATE( turb_cl_sel2(0:dlenbl) )
1194	ALLOCATE( turb_cd_sel1(0:dlenbl) )
1195	ALLOCATE( turb_cd_sel2(0:dlenbl) )
1196
1197	radres = INT( rr(1) * 10.0_wp ) + 1_iwp
1198	dlenbl_int = INT( 360.0_wp / accu_cl_cd_tab ) + 1_iwp
1199
1200
1201	ALLOCATE( turb_cl_tab(0:dlenbl_int,1:radres) )
1202	ALLOCATE( turb_cd_tab(0:dlenbl_int,1:radres) )
1203
1204
1205	DO iir = 1, radres ! loop over radius
1206
1207	DO iialpha = 1, dlenbl_int ! loop over angles
1208
1209	cur_r = ( iir - 1_iwp ) * 0.1_wp
1210	alpha_attack_i = -180.0_wp + REAL( iialpha-1 ) * accu_cl_cd_tab
1211	ialpha = 1
1212
1213	DO WHILE ( ( alpha_attack_i > alpha_attack_tab(ialpha) ) .AND. (ialpha <= dlen ) )
1214	ialpha = ialpha + 1
1215	ENDDO
1216	!
1217	!-- Find position in table
1218	lct = MINLOC( ABS( trad1 - cur_r ) )
1219	! lct(1) = lct(1)
1220
1221	IF ( ( trad1(lct(1)) - cur_r ) .GT. 0.0 ) THEN
1222	lct(1) = lct(1) - 1
1223	ENDIF
1224
1225	trow = lct(1)
1226	!
1227	!-- Calculate weights for interpolation
1228	weight_a = ( trad2(trow) - cur_r ) / ( trad2(trow) - trad1(trow) )
1229	weight_b = ( cur_r - trad1(trow) ) / ( trad2(trow) - trad1(trow) )
1230	t1 = ttoint1(trow)
1231	t2 = ttoint2(trow)
1232
1233	IF ( t1 .EQ. t2 ) THEN ! if both are the same, the weights are NaN
1234	weight_a = 0.5_wp ! then do interpolate in between same twice
1235	weight_b = 0.5_wp ! using 0.5 as weight
1236	ENDIF
1237
1238	IF ( t1 == 0 .AND. t2 == 0 ) THEN
1239	turb_cd_sel1 = 0.0_wp
1240	turb_cd_sel2 = 0.0_wp
1241	turb_cl_sel1 = 0.0_wp
1242	turb_cl_sel2 = 0.0_wp
1243	ELSE
1244	turb_cd_sel1 = turb_cd_table(:,t1)
1245	turb_cd_sel2 = turb_cd_table(:,t2)
1246	turb_cl_sel1 = turb_cl_table(:,t1)
1247	turb_cl_sel2 = turb_cl_table(:,t2)
1248	ENDIF
1249
1250	!
1251	!-- Interpolation of lift and drag coefficiencts on fine grid of radius
1252	!-- segments and angles of attack
1253
1254	turb_cl_tab(iialpha,iir) = ( alpha_attack_tab(ialpha) - &
1255	alpha_attack_i ) / &
1256	( alpha_attack_tab(ialpha) - &
1257	alpha_attack_tab(ialpha-1) ) * &
1258	( weight_a * turb_cl_sel1(ialpha-1) + &
1259	weight_b * turb_cl_sel2(ialpha-1) ) +&
1260	( alpha_attack_i - &
1261	alpha_attack_tab(ialpha-1) ) / &
1262	( alpha_attack_tab(ialpha) - &
1263	alpha_attack_tab(ialpha-1) ) * &
1264	( weight_a * turb_cl_sel1(ialpha) + &
1265	weight_b * turb_cl_sel2(ialpha) )
1266	turb_cd_tab(iialpha,iir) = ( alpha_attack_tab(ialpha) - &
1267	alpha_attack_i ) / &
1268	( alpha_attack_tab(ialpha) - &
1269	alpha_attack_tab(ialpha-1) ) * &
1270	( weight_a * turb_cd_sel1(ialpha-1) + &
1271	weight_b * turb_cd_sel2(ialpha-1) ) +&
1272	( alpha_attack_i - &
1273	alpha_attack_tab(ialpha-1) ) / &
1274	( alpha_attack_tab(ialpha) - &
1275	alpha_attack_tab(ialpha-1) ) * &
1276	( weight_a * turb_cd_sel1(ialpha) + &
1277	weight_b * turb_cd_sel2(ialpha) )
1278
1279	ENDDO ! end loop over angles of attack
1280
1281	ENDDO ! end loop over radius
1282
1283	END SUBROUTINE wtm_read_blade_tables
1284
1285
1286	!------------------------------------------------------------------------------!
1287	! Description:
1288	! ------------
1289	!> The projection matrix for the coordinate system of therotor disc in respect
1290	!> to the yaw and tilt angle of the rotor is calculated
1291	!------------------------------------------------------------------------------!
1292	SUBROUTINE wtm_rotate_rotor( inot )
1293
1294
1295	IMPLICIT NONE
1296
1297	INTEGER(iwp) :: inot
1298	!
1299	!-- Calculation of the rotation matrix for the application of the tilt to
1300	!-- the rotors
1301	rot_eigen_rad(1) = SIN( phi_yaw(inot) ) ! x-component of the radial eigenvector
1302	rot_eigen_rad(2) = COS( phi_yaw(inot) ) ! y-component of the radial eigenvector
1303	rot_eigen_rad(3) = 0.0_wp ! z-component of the radial eigenvector
1304
1305	rot_eigen_azi(1) = 0.0_wp ! x-component of the azimuth eigenvector
1306	rot_eigen_azi(2) = 0.0_wp ! y-component of the azimuth eigenvector
1307	rot_eigen_azi(3) = 1.0_wp ! z-component of the azimuth eigenvector
1308
1309	rot_eigen_nor(1) = COS( phi_yaw(inot) ) ! x-component of the normal eigenvector
1310	rot_eigen_nor(2) = -SIN( phi_yaw(inot) ) ! y-component of the normal eigenvector
1311	rot_eigen_nor(3) = 0.0_wp ! z-component of the normal eigenvector
1312
1313	!
1314	!-- Calculation of the coordinate transformation matrix to apply a tilt to
1315	!-- the rotor. If tilt = 0, rot_coord_trans is a unit matrix.
1316
1317	rot_coord_trans(inot,1,1) = rot_eigen_rad(1)*2 &
1318	( 1.0_wp - COS( tilt ) ) + COS( tilt )
1319	rot_coord_trans(inot,1,2) = rot_eigen_rad(1) * rot_eigen_rad(2) * &
1320	( 1.0_wp - COS( tilt ) ) - &
1321	rot_eigen_rad(3) * SIN( tilt )
1322	rot_coord_trans(inot,1,3) = rot_eigen_rad(1) * rot_eigen_rad(3) * &
1323	( 1.0_wp - COS( tilt ) ) + &
1324	rot_eigen_rad(2) * SIN( tilt )
1325	rot_coord_trans(inot,2,1) = rot_eigen_rad(2) * rot_eigen_rad(1) * &
1326	( 1.0_wp - COS( tilt ) ) + &
1327	rot_eigen_rad(3) * SIN( tilt )
1328	rot_coord_trans(inot,2,2) = rot_eigen_rad(2)*2 &
1329	( 1.0_wp - COS( tilt ) ) + COS( tilt )
1330	rot_coord_trans(inot,2,3) = rot_eigen_rad(2) * rot_eigen_rad(3) * &
1331	( 1.0_wp - COS( tilt ) ) - &
1332	rot_eigen_rad(1) * SIN( tilt )
1333	rot_coord_trans(inot,3,1) = rot_eigen_rad(3) * rot_eigen_rad(1) * &
1334	( 1.0_wp - COS( tilt ) ) - &
1335	rot_eigen_rad(2) * SIN( tilt )
1336	rot_coord_trans(inot,3,2) = rot_eigen_rad(3) * rot_eigen_rad(2) * &
1337	( 1.0_wp - COS( tilt ) ) + &
1338	rot_eigen_rad(1) * SIN( tilt )
1339	rot_coord_trans(inot,3,3) = rot_eigen_rad(3)*2 &
1340	( 1.0_wp - COS( tilt ) ) + COS( tilt )
1341
1342	!
1343	!-- Vectors for the Transformation of forces from the rotor's spheric
1344	!-- coordinate system to the cartesian coordinate system
1345	rotx(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_nor )
1346	roty(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_rad )
1347	rotz(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_azi )
1348
1349	END SUBROUTINE wtm_rotate_rotor
1350
1351
1352	!------------------------------------------------------------------------------!
1353	! Description:
1354	! ------------
1355	!> Calculation of the forces generated by the wind turbine
1356	!------------------------------------------------------------------------------!
1357	SUBROUTINE wtm_forces
1358
1359
1360	IMPLICIT NONE
1361
1362	CHARACTER (LEN=2) :: turbine_id
1363
1364	INTEGER(iwp) :: i, j, k !< loop indices
1365	INTEGER(iwp) :: inot !< turbine loop index (turbine id)
1366	INTEGER(iwp) :: iialpha, iir !<
1367	INTEGER(iwp) :: rseg, rseg_int !<
1368	INTEGER(iwp) :: ring, ring_int !<
1369	INTEGER(iwp) :: ii, jj, kk !<
1370
1371	REAL(wp) :: flag !< flag to mask topography grid points
1372	REAL(wp) :: sin_rot, cos_rot !<
1373	REAL(wp) :: sin_yaw, cos_yaw !<
1374
1375	REAL(wp) :: aa, bb, cc, dd !< interpolation distances
1376	REAL(wp) :: gg !< interpolation volume var
1377
1378	REAL(wp) :: dist_u_3d, dist_v_3d, dist_w_3d !< smearing distances
1379
1380
1381	!
1382	! Variables for pitch control
1383	REAL(wp) :: torque_max=0.0_wp
1384	LOGICAL :: pitch_sw=.FALSE.
1385
1386	INTEGER(iwp), DIMENSION(1) :: lct=0
1387	REAL(wp), DIMENSION(1) :: rad_d=0.0_wp
1388
1389	REAL(wp) :: tl_factor !< factor for tip loss correction
1390
1391
1392	CALL cpu_log( log_point_s(61), 'wtm_forces', 'start' )
1393
1394
1395	IF ( simulated_time >= time_turbine_on ) THEN
1396
1397	!
1398	!-- Set forces to zero for each new time step:
1399	thrust(:,:,:) = 0.0_wp
1400	torque_y(:,:,:) = 0.0_wp
1401	torque_z(:,:,:) = 0.0_wp
1402	torque_total(:) = 0.0_wp
1403	rot_tend_x(:,:,:) = 0.0_wp
1404	rot_tend_y(:,:,:) = 0.0_wp
1405	rot_tend_z(:,:,:) = 0.0_wp
1406	thrust_rotor(:) = 0.0_wp
1407	!
1408	!-- Loop over number of turbines:
1409	DO inot = 1, nturbines
1410
1411	cos_yaw = COS(phi_yaw(inot))
1412	sin_yaw = SIN(phi_yaw(inot))
1413	!
1414	!-- Loop over rings of each turbine:
1415	DO ring = 1, nrings(inot)
1416
1417	thrust_seg(:) = 0.0_wp
1418	torque_seg_y(:) = 0.0_wp
1419	torque_seg_z(:) = 0.0_wp
1420	!
1421	!-- Determine distance between each ring (center) and the hub:
1422	cur_r = (ring - 0.5_wp) * delta_r(inot)
1423
1424	!
1425	!-- Loop over segments of each ring of each turbine:
1426	DO rseg = 1, nsegs(ring,inot)
1427	!
1428	!-- !-----------------------------------------------------------!
1429	!-- !-- Determine coordinates of the ring segments --!
1430	!-- !-----------------------------------------------------------!
1431	!
1432	!-- Determine angle of ring segment towards zero degree angle of
1433	!-- rotor system (at zero degree rotor direction vectors aligned
1434	!-- with y-axis):
1435	phi_rotor = rseg * 2.0_wp * pi / nsegs(ring,inot)
1436	cos_rot = COS( phi_rotor )
1437	sin_rot = SIN( phi_rotor )
1438
1439	!-- Now the direction vectors can be determined with respect to
1440	!-- the yaw and tilt angle:
1441	re(1) = cos_rot * sin_yaw
1442	re(2) = cos_rot * cos_yaw
1443	re(3) = sin_rot
1444
1445	rote = MATMUL( rot_coord_trans(inot,:,:), re )
1446	!
1447	!-- Coordinates of the single segments (center points):
1448	rbx(ring,rseg) = rcx(inot) + cur_r * rote(1)
1449	rby(ring,rseg) = rcy(inot) + cur_r * rote(2)
1450	rbz(ring,rseg) = rcz(inot) + cur_r * rote(3)
1451
1452	!-- !-----------------------------------------------------------!
1453	!-- !-- Interpolation of the velocity components from the --!
1454	!-- !-- cartesian grid point to the coordinates of each ring --!
1455	!-- !-- segment (follows a method used in the particle model) --!
1456	!-- !-----------------------------------------------------------!
1457
1458	u_int(inot,ring,rseg) = 0.0_wp
1459	u_int_1_l(inot,ring,rseg) = 0.0_wp
1460
1461	v_int(inot,ring,rseg) = 0.0_wp
1462	v_int_1_l(inot,ring,rseg) = 0.0_wp
1463
1464	w_int(inot,ring,rseg) = 0.0_wp
1465	w_int_1_l(inot,ring,rseg) = 0.0_wp
1466
1467	!
1468	!-- Interpolation of the u-component:
1469
1470	ii = rbx(ring,rseg) * ddx
1471	jj = ( rby(ring,rseg) - 0.5_wp * dy ) * ddy
1472	kk = ( rbz(ring,rseg) - 0.5_wp * dz ) / dz
1473	!
1474	!-- Interpolate only if all required information is available on
1475	!-- the current PE:
1476	IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN
1477	IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN
1478
1479	aa = ( ( ii + 1 ) * dx - rbx(ring,rseg) ) * &
1480	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1481	bb = ( rbx(ring,rseg) - ii * dx ) * &
1482	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1483	cc = ( ( ii+1 ) * dx - rbx(ring,rseg) ) * &
1484	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1485	dd = ( rbx(ring,rseg) - ii * dx ) * &
1486	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1487	gg = dx * dy
1488
1489	u_int_l = ( aa * u(kk,jj,ii) + &
1490	bb * u(kk,jj,ii+1) + &
1491	cc * u(kk,jj+1,ii) + &
1492	dd * u(kk,jj+1,ii+1) &
1493	) / gg
1494
1495	u_int_u = ( aa * u(kk+1,jj,ii) + &
1496	bb * u(kk+1,jj,ii+1) + &
1497	cc * u(kk+1,jj+1,ii) + &
1498	dd * u(kk+1,jj+1,ii+1) &
1499	) / gg
1500
1501	u_int_1_l(inot,ring,rseg) = u_int_l + &
1502	( rbz(ring,rseg) - zu(kk) ) / dz * &
1503	( u_int_u - u_int_l )
1504
1505	ELSE
1506	u_int_1_l(inot,ring,rseg) = 0.0_wp
1507	ENDIF
1508	ELSE
1509	u_int_1_l(inot,ring,rseg) = 0.0_wp
1510	ENDIF
1511
1512
1513	!
1514	!-- Interpolation of the v-component:
1515	ii = ( rbx(ring,rseg) - 0.5_wp * dx ) * ddx
1516	jj = rby(ring,rseg) * ddy
1517	kk = ( rbz(ring,rseg) + 0.5_wp * dz ) / dz
1518	!
1519	!-- Interpolate only if all required information is available on
1520	!-- the current PE:
1521	IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN
1522	IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN
1523
1524	aa = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1525	( ( jj + 1 ) * dy - rby(ring,rseg) )
1526	bb = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1527	( ( jj + 1 ) * dy - rby(ring,rseg) )
1528	cc = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1529	( rby(ring,rseg) - jj * dy )
1530	dd = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1531	( rby(ring,rseg) - jj * dy )
1532	gg = dx * dy
1533
1534	v_int_l = ( aa * v(kk,jj,ii) + &
1535	bb * v(kk,jj,ii+1) + &
1536	cc * v(kk,jj+1,ii) + &
1537	dd * v(kk,jj+1,ii+1) &
1538	) / gg
1539
1540	v_int_u = ( aa * v(kk+1,jj,ii) + &
1541	bb * v(kk+1,jj,ii+1) + &
1542	cc * v(kk+1,jj+1,ii) + &
1543	dd * v(kk+1,jj+1,ii+1) &
1544	) / gg
1545
1546	v_int_1_l(inot,ring,rseg) = v_int_l + &
1547	( rbz(ring,rseg) - zu(kk) ) / dz * &
1548	( v_int_u - v_int_l )
1549
1550	ELSE
1551	v_int_1_l(inot,ring,rseg) = 0.0_wp
1552	ENDIF
1553	ELSE
1554	v_int_1_l(inot,ring,rseg) = 0.0_wp
1555	ENDIF
1556
1557
1558	!
1559	!-- Interpolation of the w-component:
1560	ii = ( rbx(ring,rseg) - 0.5_wp * dx ) * ddx
1561	jj = ( rby(ring,rseg) - 0.5_wp * dy ) * ddy
1562	kk = rbz(ring,rseg) / dz
1563	!
1564	!-- Interpolate only if all required information is available on
1565	!-- the current PE:
1566	IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN
1567	IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN
1568
1569	aa = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1570	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1571	bb = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1572	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1573	cc = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1574	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1575	dd = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1576	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1577	gg = dx * dy
1578
1579	w_int_l = ( aa * w(kk,jj,ii) + &
1580	bb * w(kk,jj,ii+1) + &
1581	cc * w(kk,jj+1,ii) + &
1582	dd * w(kk,jj+1,ii+1) &
1583	) / gg
1584
1585	w_int_u = ( aa * w(kk+1,jj,ii) + &
1586	bb * w(kk+1,jj,ii+1) + &
1587	cc * w(kk+1,jj+1,ii) + &
1588	dd * w(kk+1,jj+1,ii+1) &
1589	) / gg
1590
1591	w_int_1_l(inot,ring,rseg) = w_int_l + &
1592	( rbz(ring,rseg) - zw(kk) ) / dz * &
1593	( w_int_u - w_int_l )
1594	ELSE
1595	w_int_1_l(inot,ring,rseg) = 0.0_wp
1596	ENDIF
1597	ELSE
1598	w_int_1_l(inot,ring,rseg) = 0.0_wp
1599	ENDIF
1600
1601	ENDDO
1602	ENDDO
1603
1604	ENDDO
1605
1606	!
1607	!-- Exchange between PEs (information required on each PE):
1608	#if defined( __parallel )
1609	CALL MPI_ALLREDUCE( u_int_1_l, u_int, nturbines * MAXVAL(nrings) * &
1610	MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr )
1611	CALL MPI_ALLREDUCE( v_int_1_l, v_int, nturbines * MAXVAL(nrings) * &
1612	MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr )
1613	CALL MPI_ALLREDUCE( w_int_1_l, w_int, nturbines * MAXVAL(nrings) * &
1614	MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr )
1615	#else
1616	u_int = u_int_1_l
1617	v_int = v_int_1_l
1618	w_int = w_int_1_l
1619	#endif
1620
1621
1622	!
1623	!-- Loop over number of turbines:
1624
1625	DO inot = 1, nturbines
1626	pit_loop: DO
1627
1628	IF ( pitch_sw ) THEN
1629	torque_total(inot) = 0.0_wp
1630	thrust_rotor(inot) = 0.0_wp
1631	pitch_add(inot) = pitch_add(inot) + 0.25_wp
1632	! IF ( myid == 0 ) PRINT*, 'Pitch', inot, pitch_add(inot)
1633	ELSE
1634	cos_yaw = COS(phi_yaw(inot))
1635	sin_yaw = SIN(phi_yaw(inot))
1636	IF ( pitch_control ) THEN
1637	pitch_add(inot) = MAX(pitch_add_old(inot) - pitch_rate * &
1638	dt_3d , 0.0_wp )
1639	ENDIF
1640	ENDIF
1641
1642	!
1643	!-- Loop over rings of each turbine:
1644	DO ring = 1, nrings(inot)
1645	!
1646	!-- Determine distance between each ring (center) and the hub:
1647	cur_r = (ring - 0.5_wp) * delta_r(inot)
1648	!
1649	!-- Loop over segments of each ring of each turbine:
1650	DO rseg = 1, nsegs(ring,inot)
1651	!
1652	!-- Determine angle of ring segment towards zero degree angle of
1653	!-- rotor system (at zero degree rotor direction vectors aligned
1654	!-- with y-axis):
1655	phi_rotor = rseg * 2.0_wp * pi / nsegs(ring,inot)
1656	cos_rot = COS(phi_rotor)
1657	sin_rot = SIN(phi_rotor)
1658	!
1659	!-- Now the direction vectors can be determined with respect to
1660	!-- the yaw and tilt angle:
1661	re(1) = cos_rot * sin_yaw
1662	re(2) = cos_rot * cos_yaw
1663	re(3) = sin_rot
1664
1665	! The current unit vector in azimuthal direction:
1666	rea(1) = - sin_rot * sin_yaw
1667	rea(2) = - sin_rot * cos_yaw
1668	rea(3) = cos_rot
1669
1670	!
1671	!-- To respect the yawing angle for the calculations of
1672	!-- velocities and forces the unit vectors perpendicular to the
1673	!-- rotor area in direction of the positive yaw angle are defined:
1674	ren(1) = cos_yaw
1675	ren(2) = - sin_yaw
1676	ren(3) = 0.0_wp
1677	!
1678	!-- Multiplication with the coordinate transformation matrix
1679	!-- gives the final unit vector with consideration of the rotor
1680	!-- tilt:
1681	rote = MATMUL( rot_coord_trans(inot,:,:), re )
1682	rota = MATMUL( rot_coord_trans(inot,:,:), rea )
1683	rotn = MATMUL( rot_coord_trans(inot,:,:), ren )
1684	!
1685	!-- Coordinates of the single segments (center points):
1686	rbx(ring,rseg) = rcx(inot) + cur_r * rote(1)
1687
1688	rby(ring,rseg) = rcy(inot) + cur_r * rote(2)
1689
1690	rbz(ring,rseg) = rcz(inot) + cur_r * rote(3)
1691
1692	!
1693	!-- !-----------------------------------------------------------!
1694	!-- !-- Calculation of various angles and relative velocities --!
1695	!-- !-----------------------------------------------------------!
1696	!
1697	!-- In the following the 3D-velocity field is projected its
1698	!-- components perpedicular and parallel to the rotor area
1699	!-- The calculation of forces will be done in the rotor-
1700	!-- coordinates y' and z.
1701	!-- The yaw angle will be reintroduced when the force is applied
1702	!-- on the hydrodynamic equations
1703	!
1704	!-- Projection of the xy-velocities relative to the rotor area
1705	!
1706	!-- Velocity perpendicular to the rotor area:
1707	u_rot = u_int(inot,ring,rseg)*rotn(1) + &
1708	v_int(inot,ring,rseg)*rotn(2) + &
1709	w_int(inot,ring,rseg)*rotn(3)
1710	!
1711	!-- Projection of the 3D-velocity vector in the azimuthal
1712	!-- direction:
1713	vtheta(rseg) = rota(1) * u_int(inot,ring,rseg) + &
1714	rota(2) * v_int(inot,ring,rseg) + &
1715	rota(3) * w_int(inot,ring,rseg)
1716	!
1717	!-- Determination of the angle phi_rel between the rotor plane
1718	!-- and the direction of the flow relative to the rotor:
1719
1720	phi_rel(rseg) = ATAN( u_rot / &
1721	( omega_rot(inot) * cur_r - &
1722	vtheta(rseg) ) )
1723
1724	!
1725	!-- Interpolation of the local pitch angle from tabulated values
1726	!-- to the current radial position:
1727
1728	lct=minloc(ABS(cur_r-lrd))
1729	rad_d=cur_r-lrd(lct)
1730
1731	IF (cur_r == 0.0_wp) THEN
1732	alpha_attack(rseg) = 0.0_wp
1733	ELSE IF (cur_r >= lrd(size(ard))) THEN
1734	alpha_attack(rseg) = ( ard(size(ard)) + &
1735	ard(size(ard)-1) ) / 2.0_wp
1736	ELSE
1737	alpha_attack(rseg) = ( ard(lct(1)) * &
1738	( ( lrd(lct(1)+1) - cur_r ) / &
1739	( lrd(lct(1)+1) - lrd(lct(1)) ) &
1740	) ) + ( ard(lct(1)+1) * &
1741	( ( cur_r - lrd(lct(1)) ) / &
1742	( lrd(lct(1)+1) - lrd(lct(1)) ) ) )
1743	ENDIF
1744
1745	!
1746	!-- In Fortran radian instead of degree is used as unit for all
1747	!-- angles. Therefore, a transformation from angles given in
1748	!-- degree to angles given in radian is necessary here:
1749	alpha_attack(rseg) = alpha_attack(rseg) * &
1750	( (2.0_wp*pi) / 360.0_wp )
1751	!
1752	!-- Substraction of the local pitch angle to obtain the local
1753	!-- angle of attack:
1754	alpha_attack(rseg) = phi_rel(rseg) - alpha_attack(rseg)
1755	!
1756	!-- Preliminary transformation back from angles given in radian
1757	!-- to angles given in degree:
1758	alpha_attack(rseg) = alpha_attack(rseg) * &
1759	( 360.0_wp / (2.0_wp*pi) )
1760	!
1761	!-- Correct with collective pitch angle:
1762	alpha_attack = alpha_attack - pitch_add(inot)
1763
1764	!
1765	!-- Determination of the magnitude of the flow velocity relative
1766	!-- to the rotor:
1767	vrel(rseg) = SQRT( u_rot**2 + &
1768	( omega_rot(inot) * cur_r - &
1769	vtheta(rseg) )**2 )
1770
1771	!
1772	!-- !-----------------------------------------------------------!
1773	!-- !-- Interpolation of chord as well as lift and drag --!
1774	!-- !-- coefficients from tabulated values --!
1775	!-- !-----------------------------------------------------------!
1776
1777	!
1778	!-- Interpolation of the chord_length from tabulated values to
1779	!-- the current radial position:
1780
1781	IF (cur_r == 0.0_wp) THEN
1782	chord(rseg) = 0.0_wp
1783	ELSE IF (cur_r >= lrd(size(crd))) THEN
1784	chord(rseg) = (crd(size(crd)) + ard(size(crd)-1)) / 2.0_wp
1785	ELSE
1786	chord(rseg) = ( crd(lct(1)) * &
1787	( ( lrd(lct(1)+1) - cur_r ) / &
1788	( lrd(lct(1)+1) - lrd(lct(1)) ) ) ) + &
1789	( crd(lct(1)+1) * &
1790	( ( cur_r-lrd(lct(1)) ) / &
1791	( lrd(lct(1)+1) - lrd(lct(1)) ) ) )
1792	ENDIF
1793
1794	!
1795	!-- Determine index of current angle of attack, needed for
1796	!-- finding the appropriate interpolated values of the lift and
1797	!-- drag coefficients (-180.0 degrees = 0, +180.0 degrees = 36000,
1798	!-- so one index every 0.01 degrees):
1799	iialpha = CEILING( ( alpha_attack(rseg) + 180.0_wp ) &
1800	* ( 1.0_wp / accu_cl_cd_tab ) )
1801	!
1802	!-- Determine index of current radial position, needed for
1803	!-- finding the appropriate interpolated values of the lift and
1804	!-- drag coefficients (one index every 0.1 m):
1805	iir = CEILING( cur_r * 10.0_wp )
1806	!
1807	!-- Read in interpolated values of the lift and drag coefficients
1808	!-- for the current radial position and angle of attack:
1809	turb_cl(rseg) = turb_cl_tab(iialpha,iir)
1810	turb_cd(rseg) = turb_cd_tab(iialpha,iir)
1811
1812	!
1813	!-- Final transformation back from angles given in degree to
1814	!-- angles given in radian:
1815	alpha_attack(rseg) = alpha_attack(rseg) * &
1816	( (2.0_wp*pi) / 360.0_wp )
1817
1818	IF ( tl_cor ) THEN
1819
1820	!-- Tip loss correction following Schito
1821	!-- Schito applies the tip loss correction only to the lift force
1822	!-- Therefore, the tip loss correction is only applied to the lift
1823	!-- coefficient and not to the drag coefficient in our case
1824	!--
1825	tl_factor = ( 2.0 / pi ) * &
1826	ACOS( EXP( -1.0 * ( 3.0 * ( rr(inot) - cur_r ) / &
1827	( 2.0 * cur_r * abs( sin( phi_rel(rseg) ) ) ) ) ) )
1828
1829	turb_cl(rseg) = tl_factor * turb_cl(rseg)
1830
1831	END IF
1832	!
1833	!-- !-----------------------------------------------------!
1834	!-- !-- Calculation of the forces --!
1835	!-- !-----------------------------------------------------!
1836
1837	!
1838	!-- Calculate the pre_factor for the thrust and torque forces:
1839
1840	pre_factor = 0.5_wp * (vrel(rseg)*2) 3.0_wp * &
1841	chord(rseg) * delta_r(inot) / nsegs(ring,inot)
1842
1843	!
1844	!-- Calculate the thrust force (x-component of the total force)
1845	!-- for each ring segment:
1846	thrust_seg(rseg) = pre_factor * &
1847	( turb_cl(rseg) * COS(phi_rel(rseg)) + &
1848	turb_cd(rseg) * SIN(phi_rel(rseg)) )
1849
1850	!
1851	!-- Determination of the second of the additional forces acting
1852	!-- on the flow in the azimuthal direction: force vector as basis
1853	!-- for torque (torque itself would be the vector product of the
1854	!-- radius vector and the force vector):
1855	torque_seg = pre_factor * &
1856	( turb_cl(rseg) * SIN(phi_rel(rseg)) - &
1857	turb_cd(rseg) * COS(phi_rel(rseg)) )
1858	!
1859	!-- Decomposition of the force vector into two parts:
1860	!-- One acting along the y-direction and one acting along the
1861	!-- z-direction of the rotor coordinate system:
1862
1863	torque_seg_y(rseg) = -torque_seg * sin_rot
1864	torque_seg_z(rseg) = torque_seg * cos_rot
1865
1866	!
1867	!-- Add the segment thrust to the thrust of the whole rotor
1868	thrust_rotor(inot) = thrust_rotor(inot) + &
1869	thrust_seg(rseg)
1870
1871
1872	torque_total(inot) = torque_total(inot) + (torque_seg * cur_r)
1873
1874	ENDDO !-- end of loop over ring segments
1875
1876	!
1877	!-- Restore the forces into arrays containing all the segments of
1878	!-- each ring:
1879	thrust_ring(ring,:) = thrust_seg(:)
1880	torque_ring_y(ring,:) = torque_seg_y(:)
1881	torque_ring_z(ring,:) = torque_seg_z(:)
1882
1883
1884	ENDDO !-- end of loop over rings
1885
1886
1887	CALL cpu_log( log_point_s(62), 'wtm_controller', 'start' )
1888
1889
1890	IF ( speed_control ) THEN
1891	!
1892	!-- Calculation of the current generator speed for rotor speed control
1893
1894	!
1895	!-- The acceleration of the rotor speed is calculated from
1896	!-- the force balance of the accelerating torque
1897	!-- and the torque of the rotating rotor and generator
1898	om_rate = ( torque_total(inot) * air_dens * gear_eff - &
1899	gear_ratio * torque_gen_old(inot) ) / &
1900	( inertia_rot + &
1901	gear_ratio * gear_ratio * inertia_gen ) * dt_3d
1902
1903	!
1904	!-- The generator speed is given by the product of gear gear_ratio
1905	!-- and rotor speed
1906	omega_gen(inot) = gear_ratio * ( omega_rot(inot) + om_rate )
1907
1908	ENDIF
1909
1910	IF ( pitch_control ) THEN
1911
1912	!
1913	!-- If the current generator speed is above rated, the pitch is not
1914	!-- saturated and the change from the last time step is within the
1915	!-- maximum pitch rate, then the pitch loop is repeated with a pitch
1916	!-- gain
1917	IF ( ( omega_gen(inot) > rated_genspeed ) .AND. &
1918	( pitch_add(inot) < 25.0_wp ) .AND. &
1919	( pitch_add(inot) < pitch_add_old(inot) + &
1920	pitch_rate * dt_3d ) ) THEN
1921	pitch_sw = .TRUE.
1922	!
1923	!-- Go back to beginning of pit_loop
1924	CYCLE pit_loop
1925	ENDIF
1926
1927	!
1928	!-- The current pitch is saved for the next time step
1929	pitch_add_old(inot) = pitch_add(inot)
1930	pitch_sw = .FALSE.
1931	ENDIF
1932	EXIT pit_loop
1933	ENDDO pit_loop ! Recursive pitch control loop
1934
1935
1936	!
1937	!-- Call the rotor speed controller
1938
1939	IF ( speed_control ) THEN
1940	!
1941	!-- Find processor at i_hub, j_hub
1942	IF ( ( nxl <= i_hub(inot) ) .AND. ( nxr >= i_hub(inot) ) ) &
1943	THEN
1944	IF ( ( nys <= j_hub(inot) ) .AND. ( nyn >= j_hub(inot) ) )&
1945	THEN
1946	CALL wtm_speed_control( inot )
1947	ENDIF
1948	ENDIF
1949
1950	ENDIF
1951
1952
1953	CALL cpu_log( log_point_s(62), 'wtm_controller', 'stop' )
1954
1955	CALL cpu_log( log_point_s(63), 'wtm_smearing', 'start' )
1956
1957
1958	!-- !-----------------------------------------------------------------!
1959	!-- !-- Regularization kernel --!
1960	!-- !-- Smearing of the forces and interpolation to cartesian grid --!
1961	!-- !-----------------------------------------------------------------!
1962	!
1963	!-- The aerodynamic blade forces need to be distributed smoothly on
1964	!-- several mesh points in order to avoid singular behaviour
1965	!
1966	!-- Summation over sum of weighted forces. The weighting factor
1967	!-- (calculated in user_init) includes information on the distance
1968	!-- between the center of the grid cell and the rotor segment under
1969	!-- consideration
1970	!
1971	!-- To save computing time, apply smearing only for the relevant part
1972	!-- of the model domain:
1973	!
1974	!--
1975	!-- Calculation of the boundaries:
1976	i_smear(inot) = CEILING( ( rr(inot) * ABS( roty(inot,1) ) + &
1977	eps_min ) / dx )
1978	j_smear(inot) = CEILING( ( rr(inot) * ABS( roty(inot,2) ) + &
1979	eps_min ) / dy )
1980
1981	DO i = MAX( nxl, i_hub(inot) - i_smear(inot) ), &
1982	MIN( nxr, i_hub(inot) + i_smear(inot) )
1983	DO j = MAX( nys, j_hub(inot) - j_smear(inot) ), &
1984	MIN( nyn, j_hub(inot) + j_smear(inot) )
1985	! DO k = MAX( nzb_u_inner(j,i)+1, k_hub(inot) - k_smear(inot) ), &
1986	! k_hub(inot) + k_smear(inot)
1987	DO k = nzb+1, k_hub(inot) + k_smear(inot)
1988	DO ring = 1, nrings(inot)
1989	DO rseg = 1, nsegs(ring,inot)
1990	!
1991	!-- Predetermine flag to mask topography
1992	flag = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_0(k,j,i), 1 ) )
1993
1994	!
1995	!-- Determine the square of the distance between the
1996	!-- current grid point and each rotor area segment:
1997	dist_u_3d = ( i * dx - rbx(ring,rseg) )**2 + &
1998	( j * dy + 0.5_wp * dy - rby(ring,rseg) )**2 + &
1999	( k * dz - 0.5_wp * dz - rbz(ring,rseg) )**2
2000	dist_v_3d = ( i * dx + 0.5_wp * dx - rbx(ring,rseg) )**2 + &
2001	( j * dy - rby(ring,rseg) )**2 + &
2002	( k * dz - 0.5_wp * dz - rbz(ring,rseg) )**2
2003	dist_w_3d = ( i * dx + 0.5_wp * dx - rbx(ring,rseg) )**2 + &
2004	( j * dy + 0.5_wp * dy - rby(ring,rseg) )**2 + &
2005	( k * dz - rbz(ring,rseg) )**2
2006
2007	!
2008	!-- 3D-smearing of the forces with a polynomial function
2009	!-- (much faster than the old Gaussian function), using
2010	!-- some parameters that have been calculated in user_init.
2011	!-- The function is only similar to Gaussian function for
2012	!-- squared distances <= eps_min2:
2013	IF ( dist_u_3d <= eps_min2 ) THEN
2014	thrust(k,j,i) = thrust(k,j,i) + &
2015	thrust_ring(ring,rseg) * &
2016	( ( pol_a * dist_u_3d - pol_b ) * &
2017	dist_u_3d + 1.0_wp ) * eps_factor *&
2018	flag
2019	ENDIF
2020	IF ( dist_v_3d <= eps_min2 ) THEN
2021	torque_y(k,j,i) = torque_y(k,j,i) + &
2022	torque_ring_y(ring,rseg) * &
2023	( ( pol_a * dist_v_3d - pol_b ) * &
2024	dist_v_3d + 1.0_wp ) * eps_factor * &
2025	flag
2026	ENDIF
2027	IF ( dist_w_3d <= eps_min2 ) THEN
2028	torque_z(k,j,i) = torque_z(k,j,i) + &
2029	torque_ring_z(ring,rseg) * &
2030	( ( pol_a * dist_w_3d - pol_b ) * &
2031	dist_w_3d + 1.0_wp ) * eps_factor * &
2032	flag
2033	ENDIF
2034
2035	ENDDO ! End of loop over rseg
2036	ENDDO ! End of loop over ring
2037
2038	!
2039	!-- Rotation of force components:
2040	rot_tend_x(k,j,i) = rot_tend_x(k,j,i) + ( &
2041	thrust(k,j,i)*rotx(inot,1) + &
2042	torque_y(k,j,i)*roty(inot,1) + &
2043	torque_z(k,j,i)*rotz(inot,1) &
2044	) * flag
2045
2046	rot_tend_y(k,j,i) = rot_tend_y(k,j,i) + ( &
2047	thrust(k,j,i)*rotx(inot,2) + &
2048	torque_y(k,j,i)*roty(inot,2) + &
2049	torque_z(k,j,i)*rotz(inot,2) &
2050	) * flag
2051
2052	rot_tend_z(k,j,i) = rot_tend_z(k,j,i) + ( &
2053	thrust(k,j,i)*rotx(inot,3) + &
2054	torque_y(k,j,i)*roty(inot,3) + &
2055	torque_z(k,j,i)*rotz(inot,3) &
2056	) * flag
2057
2058	ENDDO ! End of loop over k
2059	ENDDO ! End of loop over j
2060	ENDDO ! End of loop over i
2061
2062	CALL cpu_log( log_point_s(63), 'wtm_smearing', 'stop' )
2063
2064	ENDDO !-- end of loop over turbines
2065
2066
2067	IF ( yaw_control ) THEN
2068	!
2069	!-- Allocate arrays for yaw control at first call
2070	!-- Can't be allocated before dt_3d is set
2071	IF ( start_up ) THEN
2072	WDLON = NINT( 30.0_wp / dt_3d ) ! 30s running mean array
2073	ALLOCATE( wd30(1:nturbines,1:WDLON) )
2074	wd30 = 999.0_wp ! Set to dummy value
2075	ALLOCATE( wd30_l(1:WDLON) )
2076
2077	WDSHO = NINT( 2.0_wp / dt_3d ) ! 2s running mean array
2078	ALLOCATE( wd2(1:nturbines,1:WDSHO) )
2079	wd2 = 999.0_wp ! Set to dummy value
2080	ALLOCATE( wd2_l(1:WDSHO) )
2081	start_up = .FALSE.
2082	ENDIF
2083
2084	!
2085	!-- Calculate the inflow wind speed
2086	!--
2087	!-- Loop over number of turbines:
2088	DO inot = 1, nturbines
2089	!
2090	!-- Find processor at i_hub, j_hub
2091	IF ( ( nxl <= i_hub(inot) ) .AND. ( nxr >= i_hub(inot) ) ) &
2092	THEN
2093	IF ( ( nys <= j_hub(inot) ) .AND. ( nyn >= j_hub(inot) ) )&
2094	THEN
2095
2096	u_inflow_l(inot) = u(k_hub(inot),j_hub(inot),i_hub(inot))
2097
2098	wdir_l(inot) = -1.0_wp * ATAN2( &
2099	0.5_wp * ( v(k_hub(inot),j_hub(inot),i_hub(inot)+1) + &
2100	v(k_hub(inot),j_hub(inot),i_hub(inot)) ) , &
2101	0.5_wp * ( u(k_hub(inot),j_hub(inot)+1,i_hub(inot)) + &
2102	u(k_hub(inot),j_hub(inot),i_hub(inot)) ) )
2103
2104	CALL wtm_yawcontrol( inot )
2105
2106	phi_yaw_l(inot) = phi_yaw(inot)
2107
2108	ENDIF
2109	ENDIF
2110
2111	ENDDO !-- end of loop over turbines
2112
2113	!
2114	!-- Transfer of information to the other cpus
2115	#if defined( __parallel )
2116	CALL MPI_ALLREDUCE( u_inflow_l, u_inflow, nturbines, MPI_REAL, &
2117	MPI_SUM, comm2d, ierr )
2118	CALL MPI_ALLREDUCE( wdir_l, wdir, nturbines, MPI_REAL, MPI_SUM, &
2119	comm2d, ierr )
2120	CALL MPI_ALLREDUCE( phi_yaw_l, phi_yaw, nturbines, MPI_REAL, &
2121	MPI_SUM, comm2d, ierr )
2122	#else
2123	u_inflow = u_inflow_l
2124	wdir = wdir_l
2125	phi_yaw = phi_yaw_l
2126
2127
2128	#endif
2129	DO inot = 1, nturbines
2130	!
2131	!-- Update rotor orientation
2132	CALL wtm_rotate_rotor( inot )
2133
2134	ENDDO ! End of loop over turbines
2135
2136	END IF ! end of yaw control
2137
2138	IF ( speed_control ) THEN
2139	!
2140	!-- Transfer of information to the other cpus
2141	! CALL MPI_ALLREDUCE( omega_gen, omega_gen_old, nturbines, &
2142	! MPI_REAL,MPI_SUM, comm2d, ierr )
2143	#if defined( __parallel )
2144	CALL MPI_ALLREDUCE( torque_gen, torque_gen_old, nturbines, &
2145	MPI_REAL, MPI_SUM, comm2d, ierr )
2146	CALL MPI_ALLREDUCE( omega_rot_l, omega_rot, nturbines, &
2147	MPI_REAL, MPI_SUM, comm2d, ierr )
2148	CALL MPI_ALLREDUCE( omega_gen_f, omega_gen_f_old, nturbines, &
2149	MPI_REAL, MPI_SUM, comm2d, ierr )
2150	#else
2151	torque_gen_old = torque_gen
2152	omega_rot = omega_rot_l
2153	omega_gen_f_old = omega_gen_f
2154	#endif
2155
2156	ENDIF
2157
2158	DO inot = 1, nturbines
2159
2160	IF ( myid == 0 ) THEN
2161	IF ( openfile_turb_mod(400+inot)%opened ) THEN
2162	WRITE ( 400+inot, 106 ) simulated_time, omega_rot(inot), &
2163	omega_gen(inot), torque_gen_old(inot), &
2164	torque_total(inot), pitch_add(inot), &
2165	torque_gen_old(inot)omega_gen(inot)gen_eff, &
2166	torque_total(inot)omega_rot(inot)air_dens, &
2167	thrust_rotor(inot), &
2168	wdir(inot)*180.0_wp/pi, &
2169	(phi_yaw(inot))*180.0_wp/pi
2170
2171	ELSE
2172
2173	WRITE ( turbine_id,'(I2.2)') inot
2174	OPEN ( 400+inot, FILE=( 'TURBINE_PARAMETERS'//turbine_id ), &
2175	FORM='FORMATTED' )
2176	WRITE ( 400+inot, 105 ) inot
2177	WRITE ( 400+inot, 106 ) simulated_time, omega_rot(inot), &
2178	omega_gen(inot), torque_gen_old(inot), &
2179	torque_total(inot), pitch_add(inot), &
2180	torque_gen_old(inot)omega_gen(inot)gen_eff, &
2181	torque_total(inot)omega_rot(inot)air_dens, &
2182	thrust_rotor(inot), &
2183	wdir(inot)*180.0_wp/pi, &
2184	(phi_yaw(inot))*180.0_wp/pi
2185	ENDIF
2186	ENDIF
2187
2188	!-- Set open flag
2189	openfile_turb_mod(400+inot)%opened = .TRUE.
2190	ENDDO !-- end of loop over turbines
2191
2192	ENDIF
2193
2194	CALL cpu_log( log_point_s(61), 'wtm_forces', 'stop' )
2195
2196	!
2197	!-- Formats
2198	105 FORMAT ('Turbine control data for turbine ',I2,1X,':'/ &
2199	&'----------------------------------------'/ &
2200	&' Time RSpeed GSpeed ', &
2201	'GenTorque AeroTorque Pitch Power(Gen) Power(Rot) ', &
2202	'RotThrust WDirection YawOrient')
2203
2204	106 FORMAT (F9.3,2X,F7.3,2X,F7.2,2X,F9.1,3X,F9.1,1X,F6.2,2X,F10.1,2X, &
2205	F10.1,1X,F9.1,2X,F7.2,1X,F7.2)
2206
2207
2208	END SUBROUTINE wtm_forces
2209
2210
2211	!------------------------------------------------------------------------------!
2212	! Description:
2213	! ------------
2214	!> Yaw controller for the wind turbine model
2215	!------------------------------------------------------------------------------!
2216	SUBROUTINE wtm_yawcontrol( inot )
2217
2218	USE constants
2219	USE kinds
2220
2221	IMPLICIT NONE
2222
2223	INTEGER(iwp) :: inot
2224	INTEGER(iwp) :: i_wd_30
2225	REAL(wp) :: missal
2226
2227	i_wd_30 = 0_iwp
2228
2229	!
2230	!-- The yaw controller computes a 30s running mean of the wind direction.
2231	!-- If the difference between turbine alignment and wind direction exceeds
2232	!-- 5Â°, the turbine is yawed. The mechanism stops as soon as the 2s-running
2233	!-- mean of the missalignment is smaller than 0.5Â°.
2234	!-- Attention: If the timestep during the simulation changes significantly
2235	!-- the lengths of the running means change and it does not correspond to
2236	!-- 30s/2s anymore.
2237	!-- ! Needs to be modified for these situations !
2238	!-- For wind from the east, the averaging of the wind direction could cause
2239	!-- problems and the yaw controller is probably flawed. -> Routine for
2240	!-- averaging needs to be improved!
2241	!
2242	!-- Check if turbine is not yawing
2243	IF ( .NOT. doyaw(inot) ) THEN
2244	!
2245	!-- Write current wind direction into array
2246	wd30_l = wd30(inot,:)
2247	wd30_l = CSHIFT( wd30_l, SHIFT=-1 )
2248	wd30_l(1) = wdir(inot)
2249	!
2250	!-- Check if array is full ( no more dummies )
2251	IF ( .NOT. ANY( wd30_l == 999.) ) THEN
2252
2253	missal = SUM( wd30_l ) / SIZE( wd30_l ) - phi_yaw(inot)
2254	!
2255	!-- Check if turbine is missaligned by more than max_miss
2256	IF ( ABS( missal ) > max_miss ) THEN
2257	!
2258	!-- Check in which direction to yaw
2259	yawdir(inot) = SIGN( 1.0_wp, missal )
2260	!
2261	!-- Start yawing of turbine
2262	phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d
2263	doyaw(inot) = .TRUE.
2264	wd30_l = 999. ! fill with dummies again
2265	ENDIF
2266	ENDIF
2267
2268	wd30(inot,:) = wd30_l
2269
2270	!
2271	!-- If turbine is already yawing:
2272	!-- Initialize 2 s running mean and yaw until the missalignment is smaller
2273	!-- than min_miss
2274
2275	ELSE
2276	!
2277	!-- Initialize 2 s running mean
2278	wd2_l = wd2(inot,:)
2279	wd2_l = CSHIFT( wd2_l, SHIFT = -1 )
2280	wd2_l(1) = wdir(inot)
2281	!
2282	!-- Check if array is full ( no more dummies )
2283	IF ( .NOT. ANY( wd2_l == 999.0_wp ) ) THEN
2284	!
2285	!-- Calculate missalignment of turbine
2286	missal = SUM( wd2_l - phi_yaw(inot) ) / SIZE( wd2_l )
2287	!
2288	!-- Check if missalignment is still larger than 0.5 degree and if the
2289	!-- yaw direction is still right
2290	IF ( ( ABS( missal ) > min_miss ) .AND. &
2291	( yawdir(inot) == SIGN( 1.0_wp, missal ) ) ) THEN
2292	!
2293	!-- Continue yawing
2294	phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d
2295	ELSE
2296	!
2297	!-- Stop yawing
2298	doyaw(inot) = .FALSE.
2299	wd2_l = 999.0_wp ! fill with dummies again
2300	ENDIF
2301	ELSE
2302	!
2303	!-- Continue yawing
2304	phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d
2305	ENDIF
2306
2307	wd2(inot,:) = wd2_l
2308
2309	ENDIF
2310
2311	END SUBROUTINE wtm_yawcontrol
2312
2313
2314	!------------------------------------------------------------------------------!
2315	! Description:
2316	! ------------
2317	!> Initialization of the speed control
2318	!------------------------------------------------------------------------------!
2319	SUBROUTINE wtm_init_speed_control
2320
2321
2322	IMPLICIT NONE
2323
2324	!
2325	!-- If speed control is set, remaining variables and control_parameters for
2326	!-- the control algorithm are calculated
2327	!
2328	!-- Calculate slope constant for region 15
2329	slope15 = ( slope2 * min_reg2 * min_reg2 ) / ( min_reg2 - min_reg15 )
2330	!
2331	!-- Calculate upper limit of slipage region
2332	vs_sysp = rated_genspeed / 1.1_wp
2333	!
2334	!-- Calculate slope of slipage region
2335	slope25 = ( rated_power / rated_genspeed ) / &
2336	( rated_genspeed - vs_sysp )
2337	!
2338	!-- Calculate lower limit of slipage region
2339	min_reg25 = ( slope25 - SQRT( slope25 * ( slope25 - 4.0_wp * &
2340	slope2 * vs_sysp ) ) ) / &
2341	( 2.0_wp * slope2 )
2342	!
2343	!-- Frequency for the simple low pass filter
2344	Fcorner = 0.25_wp
2345	!
2346	!-- At the first timestep the torque is set to its maximum to prevent
2347	!-- an overspeeding of the rotor
2348	torque_gen_old(:) = max_torque_gen
2349
2350	END SUBROUTINE wtm_init_speed_control
2351
2352
2353	!------------------------------------------------------------------------------!
2354	! Description:
2355	! ------------
2356	!> Simple controller for the regulation of the rotor speed
2357	!------------------------------------------------------------------------------!
2358	SUBROUTINE wtm_speed_control( inot )
2359
2360
2361	IMPLICIT NONE
2362
2363	INTEGER(iwp) :: inot
2364
2365
2366
2367	!
2368	!-- The controller is based on the fortran script from Jonkman
2369	!-- et al. 2009 "Definition of a 5 MW Reference Wind Turbine for
2370	!-- offshore system developement"
2371
2372	!
2373	!-- The generator speed is filtered by a low pass filter
2374	!-- for the control of the generator torque
2375	lp_coeff = EXP( -2.0_wp * 3.14_wp * dt_3d * Fcorner )
2376	omega_gen_f(inot) = ( 1.0_wp - lp_coeff ) * omega_gen(inot) + lp_coeff *&
2377	omega_gen_f_old(inot)
2378
2379	IF ( omega_gen_f(inot) <= min_reg15 ) THEN
2380	!
2381	!-- Region 1: Generator torque is set to zero to accelerate the rotor:
2382	torque_gen(inot) = 0
2383
2384	ELSEIF ( omega_gen_f(inot) <= min_reg2 ) THEN
2385	!
2386	!-- Region 1.5: Generator torque is increasing linearly with rotor speed:
2387	torque_gen(inot) = slope15 * ( omega_gen_f(inot) - min_reg15 )
2388
2389	ELSEIF ( omega_gen_f(inot) <= min_reg25 ) THEN
2390	!
2391	!-- Region 2: Generator torque is increased by the square of the generator
2392	!-- speed to keep the TSR optimal:
2393	torque_gen(inot) = slope2 * omega_gen_f(inot) * omega_gen_f(inot)
2394
2395	ELSEIF ( omega_gen_f(inot) < rated_genspeed ) THEN
2396	!
2397	!-- Region 2.5: Slipage region between 2 and 3:
2398	torque_gen(inot) = slope25 * ( omega_gen_f(inot) - vs_sysp )
2399
2400	ELSE
2401	!
2402	!-- Region 3: Generator torque is antiproportional to the rotor speed to
2403	!-- keep the power constant:
2404	torque_gen(inot) = rated_power / omega_gen_f(inot)
2405
2406	ENDIF
2407	!
2408	!-- Calculate torque rate and confine with a max
2409	trq_rate = ( torque_gen(inot) - torque_gen_old(inot) ) / dt_3d
2410	trq_rate = MIN( MAX( trq_rate, -1.0_wp * max_trq_rate ), max_trq_rate )
2411	!
2412	!-- Calculate new gen torque and confine with max torque
2413	torque_gen(inot) = torque_gen_old(inot) + trq_rate * dt_3d
2414	torque_gen(inot) = MIN( torque_gen(inot), max_torque_gen )
2415	!
2416	!-- Overwrite values for next timestep
2417	omega_rot_l(inot) = omega_gen(inot) / gear_ratio
2418
2419
2420	END SUBROUTINE wtm_speed_control
2421
2422
2423	!------------------------------------------------------------------------------!
2424	! Description:
2425	! ------------
2426	!> Application of the additional forces generated by the wind turbine on the
2427	!> flow components (tendency terms)
2428	!> Call for all grid points
2429	!------------------------------------------------------------------------------!
2430	SUBROUTINE wtm_tendencies( component )
2431
2432
2433	IMPLICIT NONE
2434
2435	INTEGER(iwp) :: component !< prognostic variable (u,v,w)
2436	INTEGER(iwp) :: i !< running index
2437	INTEGER(iwp) :: j !< running index
2438	INTEGER(iwp) :: k !< running index
2439
2440
2441	SELECT CASE ( component )
2442
2443	CASE ( 1 )
2444	!
2445	!-- Apply the x-component of the force to the u-component of the flow:
2446	IF ( simulated_time >= time_turbine_on ) THEN
2447	DO i = nxlg, nxrg
2448	DO j = nysg, nyng
2449	DO k = nzb+1, k_hub(1) + k_smear(1)
2450	!
2451	!-- Calculate the thrust generated by the nacelle and the tower
2452	tend_nac_x = 0.5_wp * nac_cd_surf(k,j,i) * &
2453	SIGN( u(k,j,i)**2 , u(k,j,i) )
2454	tend_tow_x = 0.5_wp * tow_cd_surf(k,j,i) * &
2455	SIGN( u(k,j,i)**2 , u(k,j,i) )
2456
2457	tend(k,j,i) = tend(k,j,i) + ( - rot_tend_x(k,j,i) &
2458	- tend_nac_x - tend_tow_x ) &
2459	* MERGE( 1.0_wp, 0.0_wp, &
2460	BTEST( wall_flags_0(k,j,i), 1 ) )
2461	ENDDO
2462	ENDDO
2463	ENDDO
2464	ENDIF
2465
2466	CASE ( 2 )
2467	!
2468	!-- Apply the y-component of the force to the v-component of the flow:
2469	IF ( simulated_time >= time_turbine_on ) THEN
2470	DO i = nxlg, nxrg
2471	DO j = nysg, nyng
2472	DO k = nzb+1, k_hub(1) + k_smear(1)
2473	tend_nac_y = 0.5_wp * nac_cd_surf(k,j,i) * &
2474	SIGN( v(k,j,i)**2 , v(k,j,i) )
2475	tend_tow_y = 0.5_wp * tow_cd_surf(k,j,i) * &
2476	SIGN( v(k,j,i)**2 , v(k,j,i) )
2477	tend(k,j,i) = tend(k,j,i) + ( - rot_tend_y(k,j,i) &
2478	- tend_nac_y - tend_tow_y ) &
2479	* MERGE( 1.0_wp, 0.0_wp, &
2480	BTEST( wall_flags_0(k,j,i), 2 ) )
2481	ENDDO
2482	ENDDO
2483	ENDDO
2484	ENDIF
2485
2486	CASE ( 3 )
2487	!
2488	!-- Apply the z-component of the force to the w-component of the flow:
2489	IF ( simulated_time >= time_turbine_on ) THEN
2490	DO i = nxlg, nxrg
2491	DO j = nysg, nyng
2492	DO k = nzb+1, k_hub(1) + k_smear(1)
2493	tend(k,j,i) = tend(k,j,i) - rot_tend_z(k,j,i) &
2494	* MERGE( 1.0_wp, 0.0_wp, &
2495	BTEST( wall_flags_0(k,j,i), 3 ) )
2496	ENDDO
2497	ENDDO
2498	ENDDO
2499	ENDIF
2500
2501
2502	CASE DEFAULT
2503
2504	WRITE( message_string, * ) 'unknown prognostic variable: ', component
2505	CALL message( 'wtm_tendencies', 'PA04??', 1, 2, 0, 6, 0 )
2506
2507	END SELECT
2508
2509
2510	END SUBROUTINE wtm_tendencies
2511
2512
2513	!------------------------------------------------------------------------------!
2514	! Description:
2515	! ------------
2516	!> Application of the additional forces generated by the wind turbine on the
2517	!> flow components (tendency terms)
2518	!> Call for grid point i,j
2519	!------------------------------------------------------------------------------!
2520	SUBROUTINE wtm_tendencies_ij( i, j, component )
2521
2522
2523	IMPLICIT NONE
2524
2525	INTEGER(iwp) :: component !< prognostic variable (u,v,w)
2526	INTEGER(iwp) :: i !< running index
2527	INTEGER(iwp) :: j !< running index
2528	INTEGER(iwp) :: k !< running index
2529
2530	SELECT CASE ( component )
2531
2532	CASE ( 1 )
2533	!
2534	!-- Apply the x-component of the force to the u-component of the flow:
2535	IF ( simulated_time >= time_turbine_on ) THEN
2536
2537	DO k = nzb+1, k_hub(1) + k_smear(1)
2538	!
2539	!-- Calculate the thrust generated by the nacelle and the tower
2540	tend_nac_x = 0.5_wp * nac_cd_surf(k,j,i) * &
2541	SIGN( u(k,j,i)**2 , u(k,j,i) )
2542	tend_tow_x = 0.5_wp * tow_cd_surf(k,j,i) * &
2543	SIGN( u(k,j,i)**2 , u(k,j,i) )
2544	tend(k,j,i) = tend(k,j,i) + ( - rot_tend_x(k,j,i) &
2545	- tend_nac_x - tend_tow_x ) &
2546	* MERGE( 1.0_wp, 0.0_wp, &
2547	BTEST( wall_flags_0(k,j,i), 1 ) )
2548	ENDDO
2549	ENDIF
2550
2551	CASE ( 2 )
2552	!
2553	!-- Apply the y-component of the force to the v-component of the flow:
2554	IF ( simulated_time >= time_turbine_on ) THEN
2555	DO k = nzb+1, k_hub(1) + k_smear(1)
2556	tend_nac_y = 0.5_wp * nac_cd_surf(k,j,i) * &
2557	SIGN( v(k,j,i)**2 , v(k,j,i) )
2558	tend_tow_y = 0.5_wp * tow_cd_surf(k,j,i) * &
2559	SIGN( v(k,j,i)**2 , v(k,j,i) )
2560	tend(k,j,i) = tend(k,j,i) + ( - rot_tend_y(k,j,i) &
2561	- tend_nac_y - tend_tow_y ) &
2562	* MERGE( 1.0_wp, 0.0_wp, &
2563	BTEST( wall_flags_0(k,j,i), 2 ) )
2564	ENDDO
2565	ENDIF
2566
2567	CASE ( 3 )
2568	!
2569	!-- Apply the z-component of the force to the w-component of the flow:
2570	IF ( simulated_time >= time_turbine_on ) THEN
2571	DO k = nzb+1, k_hub(1) + k_smear(1)
2572	tend(k,j,i) = tend(k,j,i) - rot_tend_z(k,j,i) &
2573	* MERGE( 1.0_wp, 0.0_wp, &
2574	BTEST( wall_flags_0(k,j,i), 3 ) )
2575	ENDDO
2576	ENDIF
2577
2578
2579	CASE DEFAULT
2580
2581	WRITE( message_string, * ) 'unknown prognostic variable: ', component
2582	CALL message( 'wtm_tendencies', 'PA04??', 1, 2, 0, 6, 0 )
2583
2584	END SELECT
2585
2586
2587	END SUBROUTINE wtm_tendencies_ij
2588
2589	END MODULE wind_turbine_model_mod

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