Home

Context Navigation

source: palm/trunk/SOURCE/wind_turbine_model_mod.f90 @ 2051

Last change on this file since 2051 was 2016, checked in by lvollmer, 8 years ago
last commit documented
Property svn:keywords set to `Id`
File size: 105.9 KB

Line
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 1997-2016 Leibniz Universitaet Hannover
18	!------------------------------------------------------------------------------!
19	!
20	! Current revisions:
21	! -----------------
22	!
23	!
24	! Former revisions:
25	! -----------------
26	! $Id: wind_turbine_model_mod.f90 2016 2016-09-28 08:51:19Z gronemeier $
27	!
28	! 2015 2016-09-28 08:45:18Z lvollmer
29	! Bugfix of pitch control
30	!
31	! 2000 2016-08-20 18:09:15Z knoop
32	! Forced header and separation lines into 80 columns
33	!
34	! 1929 2016-06-09 16:25:25Z suehring
35	! Bugfix: added preprocessor directives for parallel and serial mode
36	!
37	! 1914 2016-05-26 14:44:07Z witha
38	! Initial revision
39	!
40	!
41	! Description:
42	! ------------
43	!> This module calculates the effect of wind turbines on the flow fields. The
44	!> initial version contains only the advanced actuator disk with rotation method
45	!> (ADM-R).
46	!> The wind turbines include the tower effect, can be yawed and tilted.
47	!> The wind turbine model includes controllers for rotational speed, pitch and
48	!> yaw.
49	!> Currently some specifications of the NREL 5 MW reference turbine
50	!> are hardcoded whereas most input data comes from separate files (currently
51	!> external, planned to be included as namelist which will be read in
52	!> automatically).
53	!>
54	!> @todo Revise code according to PALM Coding Standard
55	!> @todo Implement ADM and ALM turbine models
56	!> @todo Generate header information
57	!> @todo Implement further parameter checks and error messages
58	!> @todo Revise and add code documentation
59	!> @todo Output turbine parameters as timeseries
60	!> @todo Include additional output variables
61	!> @todo Revise smearing the forces for turbines in yaw
62	!> @todo Revise nacelle and tower parameterization
63	!> @todo Allow different turbine types in one simulation
64	!
65	!------------------------------------------------------------------------------!
66	MODULE wind_turbine_model_mod
67
68	USE arrays_3d, &
69	ONLY: dd2zu, tend, u, v, w, zu, zw
70
71	USE constants
72
73	USE control_parameters, &
74	ONLY: dt_3d, dz, message_string, simulated_time
75
76	USE cpulog, &
77	ONLY: cpu_log, log_point_s
78
79	USE grid_variables, &
80	ONLY: ddx, dx, ddy, dy
81
82	USE indices, &
83	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nz, &
84	nzb, nzb_u_inner, nzb_v_inner, nzb_w_inner, nzt
85
86	USE kinds
87
88	USE pegrid
89
90
91	IMPLICIT NONE
92
93	PRIVATE
94
95	LOGICAL :: wind_turbine=.FALSE. !< switch for use of wind turbine model
96
97	!
98	!-- Variables specified in the namelist wind_turbine_par
99
100	INTEGER(iwp) :: nairfoils = 8 !< number of airfoils of the used turbine model (for ADM-R and ALM)
101	INTEGER(iwp) :: nturbines = 1 !< number of turbines
102
103	LOGICAL :: pitch_control = .FALSE. !< switch for use of pitch controller
104	LOGICAL :: speed_control = .FALSE. !< switch for use of speed controller
105	LOGICAL :: yaw_control = .FALSE. !< switch for use of yaw controller
106
107	REAL(wp) :: segment_length = 1.0_wp !< length of the segments, the rotor area is divided into
108	!< (in tangential direction, as factor of MIN(dx,dy,dz))
109	REAL(wp) :: segment_width = 0.5_wp !< width of the segments, the rotor area is divided into
110	!< (in radial direction, as factor of MIN(dx,dy,dz))
111	REAL(wp) :: time_turbine_on = 0.0_wp !< time at which turbines are started
112	REAL(wp) :: tilt = 0.0_wp !< vertical tilt of the rotor [degree] ( positive = backwards )
113
114	REAL(wp), DIMENSION(1:100) :: dtow = 0.0_wp !< tower diameter [m]
115	REAL(wp), DIMENSION(1:100) :: omega_rot = 0.0_wp !< inital or constant rotor speed [rad/s]
116	REAL(wp), DIMENSION(1:100) :: phi_yaw = 0.0_wp !< yaw angle [degree] ( clockwise, 0 = facing west )
117	REAL(wp), DIMENSION(1:100) :: pitch_add = 0.0_wp !< constant pitch angle
118	REAL(wp), DIMENSION(1:100) :: rcx = 9999999.9_wp !< position of hub in x-direction
119	REAL(wp), DIMENSION(1:100) :: rcy = 9999999.9_wp !< position of hub in y-direction
120	REAL(wp), DIMENSION(1:100) :: rcz = 9999999.9_wp !< position of hub in z-direction
121	REAL(wp), DIMENSION(1:100) :: rnac = 0.0_wp !< nacelle diameter [m]
122	REAL(wp), DIMENSION(1:100) :: rr = 63.0_wp !< rotor radius [m]
123	REAL(wp), DIMENSION(1:100) :: turb_cd_nacelle = 0.85_wp !< drag coefficient for nacelle
124	REAL(wp), DIMENSION(1:100) :: turb_cd_tower = 1.2_wp !< drag coefficient for tower
125
126	!
127	!-- Variables specified in the namelist for speed controller
128	!-- Default values are from the NREL 5MW research turbine (Jonkman, 2008)
129
130	REAL(wp) :: rated_power = 5296610.0_wp !< rated turbine power [W]
131	REAL(wp) :: gear_ratio = 97.0_wp !< Gear ratio from rotor to generator
132	REAL(wp) :: inertia_rot = 34784179.0_wp !< Inertia of the rotor [kg/m2]
133	REAL(wp) :: inertia_gen = 534.116_wp !< Inertia of the generator [kg/m2]
134	REAL(wp) :: gen_eff = 0.944_wp !< Electric efficiency of the generator
135	REAL(wp) :: gear_eff = 1.0_wp !< Loss between rotor and generator
136	REAL(wp) :: air_dens = 1.225_wp !< Air density to convert to W [kg/m3]
137	REAL(wp) :: rated_genspeed = 121.6805_wp !< Rated generator speed [rad/s]
138	REAL(wp) :: max_torque_gen = 47402.91_wp !< Maximum of the generator torque [Nm]
139	REAL(wp) :: slope2 = 2.332287_wp !< Slope constant for region 2
140	REAL(wp) :: min_reg2 = 91.21091_wp !< Lower generator speed boundary of region 2 [rad/s]
141	REAL(wp) :: min_reg15 = 70.16224_wp !< Lower generator speed boundary of region 1.5 [rad/s]
142	REAL(wp) :: max_trq_rate = 15000.0_wp !< Max generator torque increase [Nm/s]
143	REAL(wp) :: pitch_rate = 8.0_wp !< Max pitch rate [degree/s]
144
145
146	!
147	!-- Variables specified in the namelist for yaw control
148
149	REAL(wp) :: yaw_speed = 0.005236_wp !< speed of the yaw actuator [rad/s]
150	REAL(wp) :: max_miss = 0.08726_wp !< maximum tolerated yaw missalignment [rad]
151	REAL(wp) :: min_miss = 0.008726_wp !< minimum yaw missalignment for which the actuator stops [rad]
152
153	!
154	!-- Set flag for output files TURBINE_PARAMETERS
155	TYPE file_status
156	LOGICAL :: opened, opened_before
157	END TYPE file_status
158
159	TYPE(file_status), DIMENSION(500) :: openfile_turb_mod = &
160	file_status(.FALSE.,.FALSE.)
161
162	!
163	!-- Variables for initialization of the turbine model
164
165	INTEGER(iwp) :: inot !< turbine loop index (turbine id)
166	INTEGER(iwp) :: nsegs_max !< maximum number of segments (all turbines, required for allocation of arrays)
167	INTEGER(iwp) :: nrings_max !< maximum number of rings (all turbines, required for allocation of arrays)
168	INTEGER(iwp) :: ring !< ring loop index (ring number)
169	INTEGER(iwp) :: rr_int !<
170	INTEGER(iwp) :: upper_end !<
171
172	INTEGER(iwp), DIMENSION(1) :: lct !<
173
174	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: i_hub !< index belonging to x-position of the turbine
175	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: i_smear !< index defining the area for the smearing of the forces (x-direction)
176	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: j_hub !< index belonging to y-position of the turbine
177	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: j_smear !< index defining the area for the smearing of the forces (y-direction)
178	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: k_hub !< index belonging to hub height
179	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: k_smear !< index defining the area for the smearing of the forces (z-direction)
180	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nrings !< number of rings per turbine
181	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nsegs_total !< total number of segments per turbine
182
183	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: nsegs !< number of segments per ring and turbine
184
185	!
186	!- parameters for the smearing from the rotor to the cartesian grid
187	REAL(wp) :: pol_a !< parameter for the polynomial smearing fct
188	REAL(wp) :: pol_b !< parameter for the polynomial smearing fct
189	REAL(wp) :: delta_t_factor !<
190	REAL(wp) :: eps_factor !<
191	REAL(wp) :: eps_min !<
192	REAL(wp) :: eps_min2 !<
193	REAL(wp) :: sqrt_arg !<
194
195	!
196	!-- Variables for the calculation of lift and drag coefficients
197	REAL(wp), DIMENSION(:), ALLOCATABLE :: ard !<
198	REAL(wp), DIMENSION(:), ALLOCATABLE :: crd !<
199	REAL(wp), DIMENSION(:), ALLOCATABLE :: delta_r !< radial segment length
200	REAL(wp), DIMENSION(:), ALLOCATABLE :: lrd !<
201
202	REAL(wp) :: accu_cl_cd_tab = 0.1_wp !< Accuracy of the interpolation of
203	!< the lift and drag coeff [deg]
204
205	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cd_tab !< table of the blade drag coefficient
206	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cl_tab !< table of the blade lift coefficient
207
208	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: nac_cd_surf !< 3d field of the tower drag coefficient
209	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: tow_cd_surf !< 3d field of the nacelle drag coefficient
210
211	!
212	!-- Variables for the calculation of the forces
213
214	REAL(wp) :: cur_r !<
215	REAL(wp) :: delta_t !< tangential segment length
216	REAL(wp) :: phi_rotor !<
217	REAL(wp) :: pre_factor !<
218	REAL(wp) :: torque_seg !<
219	REAL(wp) :: u_int_l !<
220	REAL(wp) :: u_int_u !<
221	REAL(wp) :: u_rot !<
222	REAL(wp) :: v_int_l !<
223	REAL(wp) :: v_int_u !<
224	REAL(wp) :: w_int_l !<
225	REAL(wp) :: w_int_u !<
226	!
227	!- Tendencies from the nacelle and tower thrust
228	REAL(wp) :: tend_nac_x = 0.0_wp !<
229	REAL(wp) :: tend_tow_x = 0.0_wp !<
230	REAL(wp) :: tend_nac_y = 0.0_wp !<
231	REAL(wp) :: tend_tow_y = 0.0_wp !<
232
233	REAL(wp), DIMENSION(:), ALLOCATABLE :: alpha_attack !<
234	REAL(wp), DIMENSION(:), ALLOCATABLE :: chord !<
235	REAL(wp), DIMENSION(:), ALLOCATABLE :: omega_gen !< curr. generator speed
236	REAL(wp), DIMENSION(:), ALLOCATABLE :: phi_rel !<
237	REAL(wp), DIMENSION(:), ALLOCATABLE :: pitch_add_old!<
238	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_total !<
239	REAL(wp), DIMENSION(:), ALLOCATABLE :: thrust_rotor !<
240	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl !<
241	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd !<
242	REAL(wp), DIMENSION(:), ALLOCATABLE :: vrel !<
243	REAL(wp), DIMENSION(:), ALLOCATABLE :: vtheta !<
244
245	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: rbx, rby, rbz !< coordinates of the blade elements
246	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: rotx, roty, rotz !< normal vectors to the rotor coordinates
247
248	!
249	!- Fields for the interpolation of velocities on the rotor grid
250	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: u_int !<
251	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: u_int_1_l !<
252	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: v_int !<
253	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: v_int_1_l !<
254	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: w_int !<
255	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: w_int_1_l !<
256
257	!
258	!- rotor tendencies on the segments
259	REAL(wp), DIMENSION(:), ALLOCATABLE :: thrust_seg !<
260	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_seg_y !<
261	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_seg_z !<
262
263	!
264	!- rotor tendencies on the rings
265	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: thrust_ring !<
266	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: torque_ring_y !<
267	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: torque_ring_z !<
268
269	!
270	!- rotor tendencies on rotor grids for all turbines
271	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: thrust !<
272	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: torque_y !<
273	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: torque_z !<
274
275	!
276	!- rotor tendencies on coordinate grid
277	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_x !<
278	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_y !<
279	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_z !<
280	!
281	!- variables for the rotation of the rotor coordinates
282	REAL(wp), DIMENSION(1:100,1:3,1:3) :: rot_coord_trans !< matrix for rotation of rotor coordinates
283
284	REAL(wp), DIMENSION(1:3) :: rot_eigen_rad !<
285	REAL(wp), DIMENSION(1:3) :: rot_eigen_azi !<
286	REAL(wp), DIMENSION(1:3) :: rot_eigen_nor !<
287	REAL(wp), DIMENSION(1:3) :: re !<
288	REAL(wp), DIMENSION(1:3) :: rea !<
289	REAL(wp), DIMENSION(1:3) :: ren !<
290	REAL(wp), DIMENSION(1:3) :: rote !<
291	REAL(wp), DIMENSION(1:3) :: rota !<
292	REAL(wp), DIMENSION(1:3) :: rotn !<
293
294	!
295	!-- Fixed variables for the speed controller
296
297	LOGICAL :: start_up = .TRUE. !<
298
299	REAL(wp) :: Fcorner !< corner freq for the controller low pass filter
300	REAL(wp) :: min_reg25 !< min region 2.5
301	REAL(wp) :: om_rate !< rotor speed change
302	REAL(wp) :: slope15 !< slope in region 1.5
303	REAL(wp) :: slope25 !< slope in region 2.5
304	REAL(wp) :: trq_rate !< torque change
305	REAL(wp) :: vs_sysp !<
306	REAL(wp) :: lp_coeff !< coeff for the controller low pass filter
307
308	REAL(wp), DIMENSION(:), ALLOCATABLE :: omega_gen_old !< last gen. speed
309	REAL(wp), DIMENSION(:), ALLOCATABLE :: omega_gen_f !< filtered gen. sp
310	REAL(wp), DIMENSION(:), ALLOCATABLE :: omega_gen_f_old !< last filt. gen. sp
311	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_gen !< generator torque
312	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_gen_old !< last gen. torque
313
314	REAL(wp), DIMENSION(100) :: omega_rot_l = 0.0_wp !< local rot speed [rad/s]
315	!
316	!-- Fixed variables for the yaw controller
317
318	REAL(wp), DIMENSION(:) , ALLOCATABLE :: yawdir !< direction to yaw
319	REAL(wp), DIMENSION(:) , ALLOCATABLE :: phi_yaw_l !< local (cpu) yaw angle
320	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wd30_l !< local (cpu) long running avg of the wd
321	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wd2_l !< local (cpu) short running avg of the wd
322	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wdir !< wind direction at hub
323	REAL(wp), DIMENSION(:) , ALLOCATABLE :: u_inflow !< wind speed at hub
324	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wdir_l !<
325	REAL(wp), DIMENSION(:) , ALLOCATABLE :: u_inflow_l !<
326	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: wd30 !<
327	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: wd2 !<
328	LOGICAL, DIMENSION(1:100) :: doyaw = .FALSE. !<
329	INTEGER(iwp) :: WDLON !<
330	INTEGER(iwp) :: WDSHO !<
331
332
333	SAVE
334
335
336	INTERFACE wtm_parin
337	MODULE PROCEDURE wtm_parin
338	END INTERFACE wtm_parin
339
340	INTERFACE wtm_check_parameters
341	MODULE PROCEDURE wtm_check_parameters
342	END INTERFACE wtm_check_parameters
343
344	INTERFACE wtm_init_arrays
345	MODULE PROCEDURE wtm_init_arrays
346	END INTERFACE wtm_init_arrays
347
348	INTERFACE wtm_init
349	MODULE PROCEDURE wtm_init
350	END INTERFACE wtm_init
351
352	INTERFACE wtm_read_blade_tables
353	MODULE PROCEDURE wtm_read_blade_tables
354	END INTERFACE wtm_read_blade_tables
355
356	INTERFACE wtm_forces
357	MODULE PROCEDURE wtm_forces
358	MODULE PROCEDURE wtm_yawcontrol
359	END INTERFACE wtm_forces
360
361	INTERFACE wtm_rotate_rotor
362	MODULE PROCEDURE wtm_rotate_rotor
363	END INTERFACE wtm_rotate_rotor
364
365	INTERFACE wtm_speed_control
366	MODULE PROCEDURE wtm_init_speed_control
367	MODULE PROCEDURE wtm_speed_control
368	END INTERFACE wtm_speed_control
369
370	INTERFACE wtm_tendencies
371	MODULE PROCEDURE wtm_tendencies
372	MODULE PROCEDURE wtm_tendencies_ij
373	END INTERFACE wtm_tendencies
374
375
376	PUBLIC wtm_check_parameters, wtm_forces, wtm_init, wtm_init_arrays, &
377	wtm_parin, wtm_tendencies, wtm_tendencies_ij, wind_turbine
378
379	CONTAINS
380
381
382	!------------------------------------------------------------------------------!
383	! Description:
384	! ------------
385	!> Parin for &wind_turbine_par for wind turbine model
386	!------------------------------------------------------------------------------!
387	SUBROUTINE wtm_parin
388
389
390	IMPLICIT NONE
391
392	INTEGER(iwp) :: ierrn !<
393
394	CHARACTER (LEN=80) :: line !< dummy string that contains the current line of the parameter file
395
396	NAMELIST /wind_turbine_par/ air_dens, dtow, gear_eff, gear_ratio, &
397	gen_eff, inertia_gen, inertia_rot, max_miss, &
398	max_torque_gen, max_trq_rate, min_miss, &
399	min_reg15, min_reg2, nairfoils, nturbines, &
400	omega_rot, phi_yaw, pitch_add, pitch_control,&
401	rated_genspeed, rated_power, rcx, rcy, rcz, &
402	rnac, rr, segment_length, segment_width, &
403	slope2, speed_control, tilt, time_turbine_on,&
404	turb_cd_nacelle, turb_cd_tower, &
405	yaw_control, yaw_speed
406
407	!
408	!-- Try to find wind turbine model package
409	REWIND ( 11 )
410	line = ' '
411	DO WHILE ( INDEX( line, '&wind_turbine_par' ) == 0 )
412	READ ( 11, '(A)', END=10 ) line
413	ENDDO
414	BACKSPACE ( 11 )
415
416	!
417	!-- Read user-defined namelist
418	READ ( 11, wind_turbine_par, IOSTAT=ierrn )
419
420	IF ( ierrn < 0 ) THEN
421	message_string = 'errors in \$wind_turbine_par'
422	CALL message( 'wtm_parin', 'PA0???', 1, 2, 0, 6, 0 )
423	ENDIF
424
425	!
426	!-- Set flag that indicates that the wind turbine model is switched on
427	wind_turbine = .TRUE.
428
429	10 CONTINUE ! TBD Change from continue, mit ierrn machen
430
431
432	END SUBROUTINE wtm_parin
433
434	SUBROUTINE wtm_check_parameters
435
436
437	IMPLICIT NONE
438
439	IF ( ( .NOT.speed_control ) .AND. pitch_control ) THEN
440	message_string = 'pitch_control = .TRUE. requires '// &
441	'speed_control = .TRUE.'
442	CALL message( 'wtm_check_parameters', 'PA0???', 1, 2, 0, 6, 0 )
443	ENDIF
444
445	IF ( ANY( omega_rot(1:nturbines) <= 0.0 ) ) THEN
446	message_string = 'omega_rot <= 0.0, Please set omega_rot to ' // &
447	'a value larger than zero'
448	CALL message( 'wtm_check_parameters', 'PA0???', 1, 2, 0, 6, 0 )
449	ENDIF
450
451
452	IF ( ANY( rcx(1:nturbines) == 9999999.9_wp ) .OR. &
453	ANY( rcy(1:nturbines) == 9999999.9_wp ) .OR. &
454	ANY( rcz(1:nturbines) == 9999999.9_wp ) ) THEN
455
456	message_string = 'rcx, rcy, rcz ' // &
457	'have to be given for each turbine.'
458	CALL message( 'wtm_check_parameters', 'PA0???', 1, 2, 0, 6, 0 )
459
460	ENDIF
461
462
463	END SUBROUTINE wtm_check_parameters
464
465
466	!------------------------------------------------------------------------------!
467	! Description:
468	! ------------
469	!> Allocate wind turbine model arrays
470	!------------------------------------------------------------------------------!
471	SUBROUTINE wtm_init_arrays
472
473
474	IMPLICIT NONE
475
476	REAL(wp) :: delta_r_factor !<
477	REAL(wp) :: delta_r_init !<
478
479	!
480	!-- To be able to allocate arrays with dimension of rotor rings and segments,
481	!-- the maximum possible numbers of rings and segments have to be calculated:
482
483	ALLOCATE( nrings(1:nturbines) )
484	ALLOCATE( delta_r(1:nturbines) )
485
486	nrings(:) = 0
487	delta_r(:) = 0.0_wp
488
489	!
490	!-- Thickness (radial) of each ring and length (tangential) of each segment:
491	delta_r_factor = segment_width
492	delta_t_factor = segment_length
493	delta_r_init = delta_r_factor * MIN( dx, dy, dz)
494	delta_t = delta_t_factor * MIN( dx, dy, dz)
495
496	DO inot = 1, nturbines
497	!
498	!-- Determine number of rings:
499	nrings(inot) = NINT( rr(inot) / delta_r_init )
500
501	delta_r(inot) = rr(inot) / nrings(inot)
502
503	ENDDO
504
505	nrings_max = MAXVAL(nrings)
506
507	ALLOCATE( nsegs(1:nrings_max,1:nturbines) )
508	ALLOCATE( nsegs_total(1:nturbines) )
509
510	nsegs(:,:) = 0
511	nsegs_total(:) = 0
512
513
514	DO inot = 1, nturbines
515	DO ring = 1, nrings(inot)
516	!
517	!-- Determine number of segments for each ring:
518	nsegs(ring,inot) = MAX( 8, CEILING( delta_r_factor * pi * &
519	( 2.0_wp * ring - 1.0_wp ) / &
520	delta_t_factor ) )
521	ENDDO
522	!
523	!-- Total sum of all rotor segments:
524	nsegs_total(inot) = SUM( nsegs(:,inot) )
525
526	ENDDO
527
528	!
529	!-- Maximum number of segments per ring:
530	nsegs_max = MAXVAL(nsegs)
531
532	!!
533	!!-- TODO: Folgendes im Header ausgeben!
534	! IF ( myid == 0 ) THEN
535	! PRINT*, 'nrings(1) = ', nrings(1)
536	! PRINT*, '--------------------------------------------------'
537	! PRINT*, 'nsegs(:,1) = ', nsegs(:,1)
538	! PRINT*, '--------------------------------------------------'
539	! PRINT*, 'nrings_max = ', nrings_max
540	! PRINT*, 'nsegs_max = ', nsegs_max
541	! PRINT*, 'nsegs_total(1) = ', nsegs_total(1)
542	! ENDIF
543
544
545	!
546	!-- Allocate 1D arrays (dimension = number of turbines)
547	ALLOCATE( i_hub(1:nturbines) )
548	ALLOCATE( i_smear(1:nturbines) )
549	ALLOCATE( j_hub(1:nturbines) )
550	ALLOCATE( j_smear(1:nturbines) )
551	ALLOCATE( k_hub(1:nturbines) )
552	ALLOCATE( k_smear(1:nturbines) )
553	ALLOCATE( torque_total(1:nturbines) )
554	ALLOCATE( thrust_rotor(1:nturbines) )
555
556	!
557	!-- Allocation of the 1D arrays for speed pitch_control
558	ALLOCATE( omega_gen(1:nturbines) )
559	ALLOCATE( omega_gen_old(1:nturbines) )
560	ALLOCATE( omega_gen_f(1:nturbines) )
561	ALLOCATE( omega_gen_f_old(1:nturbines) )
562	ALLOCATE( pitch_add_old(1:nturbines) )
563	ALLOCATE( torque_gen(1:nturbines) )
564	ALLOCATE( torque_gen_old(1:nturbines) )
565
566	!
567	!-- Allocation of the 1D arrays for yaw control
568	ALLOCATE( yawdir(1:nturbines) )
569	ALLOCATE( u_inflow(1:nturbines) )
570	ALLOCATE( wdir(1:nturbines) )
571	ALLOCATE( u_inflow_l(1:nturbines) )
572	ALLOCATE( wdir_l(1:nturbines) )
573	ALLOCATE( phi_yaw_l(1:nturbines) )
574
575	!
576	!-- Allocate 1D arrays (dimension = number of rotor segments)
577	ALLOCATE( alpha_attack(1:nsegs_max) )
578	ALLOCATE( chord(1:nsegs_max) )
579	ALLOCATE( phi_rel(1:nsegs_max) )
580	ALLOCATE( thrust_seg(1:nsegs_max) )
581	ALLOCATE( torque_seg_y(1:nsegs_max) )
582	ALLOCATE( torque_seg_z(1:nsegs_max) )
583	ALLOCATE( turb_cd(1:nsegs_max) )
584	ALLOCATE( turb_cl(1:nsegs_max) )
585	ALLOCATE( vrel(1:nsegs_max) )
586	ALLOCATE( vtheta(1:nsegs_max) )
587
588	!
589	!-- Allocate 2D arrays (dimension = number of rotor rings and segments)
590	ALLOCATE( rbx(1:nrings_max,1:nsegs_max) )
591	ALLOCATE( rby(1:nrings_max,1:nsegs_max) )
592	ALLOCATE( rbz(1:nrings_max,1:nsegs_max) )
593	ALLOCATE( thrust_ring(1:nrings_max,1:nsegs_max) )
594	ALLOCATE( torque_ring_y(1:nrings_max,1:nsegs_max) )
595	ALLOCATE( torque_ring_z(1:nrings_max,1:nsegs_max) )
596
597	!
598	!-- Allocate additional 2D arrays
599	ALLOCATE( rotx(1:nturbines,1:3) )
600	ALLOCATE( roty(1:nturbines,1:3) )
601	ALLOCATE( rotz(1:nturbines,1:3) )
602
603	!
604	!-- Allocate 3D arrays (dimension = number of grid points)
605	ALLOCATE( nac_cd_surf(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
606	ALLOCATE( rot_tend_x(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
607	ALLOCATE( rot_tend_y(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
608	ALLOCATE( rot_tend_z(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
609	ALLOCATE( thrust(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
610	ALLOCATE( torque_y(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
611	ALLOCATE( torque_z(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
612	ALLOCATE( tow_cd_surf(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
613
614	!
615	!-- Allocate additional 3D arrays
616	ALLOCATE( u_int(1:nturbines,1:nrings_max,1:nsegs_max) )
617	ALLOCATE( u_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) )
618	ALLOCATE( v_int(1:nturbines,1:nrings_max,1:nsegs_max) )
619	ALLOCATE( v_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) )
620	ALLOCATE( w_int(1:nturbines,1:nrings_max,1:nsegs_max) )
621	ALLOCATE( w_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) )
622
623	!
624	!-- All of the arrays are initialized with a value of zero:
625	i_hub(:) = 0
626	i_smear(:) = 0
627	j_hub(:) = 0
628	j_smear(:) = 0
629	k_hub(:) = 0
630	k_smear(:) = 0
631
632	torque_total(:) = 0.0_wp
633	thrust_rotor(:) = 0.0_wp
634
635	omega_gen(:) = 0.0_wp
636	omega_gen_old(:) = 0.0_wp
637	omega_gen_f(:) = 0.0_wp
638	omega_gen_f_old(:) = 0.0_wp
639	pitch_add_old(:) = 0.0_wp
640	torque_gen(:) = 0.0_wp
641	torque_gen_old(:) = 0.0_wp
642
643	yawdir(:) = 0.0_wp
644	wdir(:) = 0.0_wp
645	u_inflow(:) = 0.0_wp
646
647	!
648	!-- Allocate 1D arrays (dimension = number of rotor segments)
649	alpha_attack(:) = 0.0_wp
650	chord(:) = 0.0_wp
651	phi_rel(:) = 0.0_wp
652	thrust_seg(:) = 0.0_wp
653	torque_seg_y(:) = 0.0_wp
654	torque_seg_z(:) = 0.0_wp
655	turb_cd(:) = 0.0_wp
656	turb_cl(:) = 0.0_wp
657	vrel(:) = 0.0_wp
658	vtheta(:) = 0.0_wp
659
660	rbx(:,:) = 0.0_wp
661	rby(:,:) = 0.0_wp
662	rbz(:,:) = 0.0_wp
663	thrust_ring(:,:) = 0.0_wp
664	torque_ring_y(:,:) = 0.0_wp
665	torque_ring_z(:,:) = 0.0_wp
666
667	rotx(:,:) = 0.0_wp
668	roty(:,:) = 0.0_wp
669	rotz(:,:) = 0.0_wp
670	turb_cl_tab(:,:) = 0.0_wp
671	turb_cd_tab(:,:) = 0.0_wp
672
673	nac_cd_surf(:,:,:) = 0.0_wp
674	rot_tend_x(:,:,:) = 0.0_wp
675	rot_tend_y(:,:,:) = 0.0_wp
676	rot_tend_z(:,:,:) = 0.0_wp
677	thrust(:,:,:) = 0.0_wp
678	torque_y(:,:,:) = 0.0_wp
679	torque_z(:,:,:) = 0.0_wp
680	tow_cd_surf(:,:,:) = 0.0_wp
681
682	u_int(:,:,:) = 0.0_wp
683	u_int_1_l(:,:,:) = 0.0_wp
684	v_int(:,:,:) = 0.0_wp
685	v_int_1_l(:,:,:) = 0.0_wp
686	w_int(:,:,:) = 0.0_wp
687	w_int_1_l(:,:,:) = 0.0_wp
688
689
690	END SUBROUTINE wtm_init_arrays
691
692
693	!------------------------------------------------------------------------------!
694	! Description:
695	! ------------
696	!> Initialization of the wind turbine model
697	!------------------------------------------------------------------------------!
698	SUBROUTINE wtm_init
699
700
701	IMPLICIT NONE
702
703	INTEGER(iwp) :: i !< running index
704	INTEGER(iwp) :: j !< running index
705	INTEGER(iwp) :: k !< running index
706
707	!
708	!-- Help variables for the smearing function
709	REAL(wp) :: eps_kernel !<
710
711	!
712	!-- Help variables for calculation of the tower drag
713	INTEGER(iwp) :: tower_n !<
714	INTEGER(iwp) :: tower_s !<
715	!
716	!-- Help variables for the calulaction of the nacelle drag
717	INTEGER(iwp) :: i_ip !<
718	INTEGER(iwp) :: i_ipg !<
719
720	REAL(wp) :: yvalue
721	REAL(wp) :: dy_int !<
722	REAL(wp) :: dz_int !<
723
724	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: circle_points !<
725
726	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nacb !<
727	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nacl !<
728	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nacr !<
729	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nact !<
730
731	ALLOCATE( index_nacb(1:nturbines) )
732	ALLOCATE( index_nacl(1:nturbines) )
733	ALLOCATE( index_nacr(1:nturbines) )
734	ALLOCATE( index_nact(1:nturbines) )
735
736
737	IF ( speed_control) THEN
738
739	CALL wtm_speed_control
740
741	ENDIF
742
743	!
744	!------------------------------------------------------------------------------!
745	!-- Calculation of parameters for the regularization kernel
746	!-- (smearing of the forces)
747	!------------------------------------------------------------------------------!
748	!
749	!-- In the following, some of the required parameters for the smearing will
750	!-- be calculated:
751
752	!-- The kernel is set equal to twice the grid spacing which has turned out to
753	!-- be a reasonable value (see e.g. Troldborg et al. (2013), Wind Energy,
754	!-- DOI: 10.1002/we.1608):
755	eps_kernel = 2.0_wp * dx
756	!
757	!-- The zero point (eps_min) of the polynomial function must be the following
758	!-- if the integral of the polynomial function (for values < eps_min) shall
759	!-- be equal to the integral of the Gaussian function used before:
760	eps_min = ( 105.0_wp / 32.0_wp )*( 1.0_wp / 3.0_wp ) &
761	pi*( 1.0_wp / 6.0_wp ) eps_kernel
762	!
763	!-- Square of eps_min:
764	eps_min2 = eps_min**2
765	!
766	!-- Parameters in the polynomial function:
767	pol_a = 1.0_wp / eps_min**4
768	pol_b = 2.0_wp / eps_min**2
769	!
770	!-- Normalization factor which is the inverse of the integral of the smearing
771	!-- function:
772	eps_factor = 105.0_wp / ( 32.0_wp * pi * eps_min**3 )
773
774	!-- Change tilt angle to rad:
775	tilt = tilt * pi / 180.0_wp
776
777	!
778	!-- Change yaw angle to rad:
779	phi_yaw(:) = phi_yaw(:) * pi / 180.0_wp
780
781
782	DO inot = 1, nturbines
783	!
784	!-- Rotate the rotor coordinates in case yaw and tilt are defined
785	CALL wtm_rotate_rotor( inot )
786
787	!
788	!-- Determine the indices of the hub height
789	i_hub(inot) = INT( rcx(inot) / dx )
790	j_hub(inot) = INT( ( rcy(inot) + 0.5_wp * dy ) / dy )
791	k_hub(inot) = INT( ( rcz(inot) + 0.5_wp * dz ) / dz )
792
793	!
794	!-- Determining the area to which the smearing of the forces is applied.
795	!-- As smearing now is effectively applied only for distances smaller than
796	!-- eps_min, the smearing area can be further limited and regarded as a
797	!-- function of eps_min:
798	i_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dx )
799	j_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dy )
800	k_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dz )
801
802	ENDDO
803
804	!
805	!------------------------------------------------------------------------------!
806	!-- Determine the area within each grid cell that overlaps with the area
807	!-- of the nacelle and the tower (needed for calculation of the forces)
808	!------------------------------------------------------------------------------!
809	!
810	!-- Note: so far this is only a 2D version, in that the mean flow is
811	!-- perpendicular to the rotor area.
812
813	!
814	!-- Allocation of the array containing information on the intersection points
815	!-- between rotor disk and the numerical grid:
816	upper_end = ( ny + 1 ) * 10000
817
818	ALLOCATE( circle_points(1:2,1:upper_end) )
819
820	circle_points(:,:) = 0.0_wp
821
822
823	DO inot = 1, nturbines ! loop over number of turbines
824	!
825	!-- Determine the grid index (u-grid) that corresponds to the location of
826	!-- the rotor center (reduces the amount of calculations in the case that
827	!-- the mean flow is perpendicular to the rotor area):
828	i = i_hub(inot)
829
830	!
831	!-- Determine the left and the right edge of the nacelle (corresponding
832	!-- grid point indices):
833	index_nacl(inot) = INT( ( rcy(inot) - rnac(inot) + 0.5_wp * dy ) / dy )
834	index_nacr(inot) = INT( ( rcy(inot) + rnac(inot) + 0.5_wp * dy ) / dy )
835	!
836	!-- Determine the bottom and the top edge of the nacelle (corresponding
837	!-- grid point indices).The grid point index has to be increased by 1, as
838	!-- the first level for the u-component (index 0) is situated below the
839	!-- surface. All points between z=0 and z=dz/s would already be contained
840	!-- in grid box 1.
841	index_nacb(inot) = INT( ( rcz(inot) - rnac(inot) ) / dz ) + 1
842	index_nact(inot) = INT( ( rcz(inot) + rnac(inot) ) / dz ) + 1
843
844	!
845	!-- Determine the indices of the grid boxes containing the left and
846	!-- the right boundaries of the tower:
847	tower_n = ( rcy(inot) + 0.5_wp * dtow(inot) - 0.5_wp * dy ) / dy
848	tower_s = ( rcy(inot) - 0.5_wp * dtow(inot) - 0.5_wp * dy ) / dy
849
850	!
851	!-- Determine the fraction of the grid box area overlapping with the tower
852	!-- area and multiply it with the drag of the tower:
853	IF ( ( nxlg <= i ) .AND. ( nxrg >= i ) ) THEN
854
855	DO j = nys, nyn
856	!
857	!-- Loop from south to north boundary of tower
858	IF ( ( j >= tower_s ) .AND. ( j <= tower_n ) ) THEN
859
860	DO k = nzb, nzt
861
862	IF ( k == k_hub(inot) ) THEN
863	IF ( tower_n - tower_s >= 1 ) THEN
864	!
865	!-- leftmost and rightmost grid box:
866	IF ( j == tower_s ) THEN
867	tow_cd_surf(k,j,i) = ( rcz(inot) - &
868	( k_hub(inot) * dz - 0.5_wp * dz ) ) * & ! extension in z-direction
869	( ( tower_s + 1.0_wp + 0.5_wp ) * dy - &
870	( rcy(inot) - 0.5_wp * dtow(inot) ) ) * & ! extension in y-direction
871	turb_cd_tower(inot)
872	ELSEIF ( j == tower_n ) THEN
873	tow_cd_surf(k,j,i) = ( rcz(inot) - &
874	( k_hub(inot) * dz - 0.5_wp * dz ) ) * & ! extension in z-direction
875	( ( rcy(inot) + 0.5_wp * dtow(inot) ) - &
876	( tower_n + 0.5_wp ) * dy ) * & ! extension in y-direction
877	turb_cd_tower(inot)
878	!
879	!-- grid boxes inbetween
880	!-- (where tow_cd_surf = grid box area):
881	ELSE
882	tow_cd_surf(k,j,i) = ( rcz(inot) - &
883	( k_hub(inot) * dz - 0.5_wp * dz ) ) * &
884	dy * turb_cd_tower(inot)
885	ENDIF
886	!
887	!-- tower lies completely within one grid box:
888	ELSE
889	tow_cd_surf(k,j,i) = ( rcz(inot) - &
890	( k_hub(inot) * dz - 0.5_wp * dz ) ) * &
891	dtow(inot) * turb_cd_tower(inot)
892	ENDIF
893	!
894	!-- In case that k is smaller than k_hub the following actions
895	!-- are carried out:
896	ELSEIF ( k < k_hub(inot) ) THEN
897
898	IF ( ( tower_n - tower_s ) >= 1 ) THEN
899	!
900	!-- leftmost and rightmost grid box:
901	IF ( j == tower_s ) THEN
902	tow_cd_surf(k,j,i) = dz * ( &
903	( tower_s + 1 + 0.5_wp ) * dy - &
904	( rcy(inot) - 0.5_wp * dtow(inot) ) &
905	) * turb_cd_tower(inot)
906	ELSEIF ( j == tower_n ) THEN
907	tow_cd_surf(k,j,i) = dz * ( &
908	( rcy(inot) + 0.5_wp * dtow(inot) ) - &
909	( tower_n + 0.5_wp ) * dy &
910	) * turb_cd_tower(inot)
911	!
912	!-- grid boxes inbetween
913	!-- (where tow_cd_surf = grid box area):
914	ELSE
915	tow_cd_surf(k,j,i) = dz * dy * turb_cd_tower(inot)
916	ENDIF
917	!
918	!-- tower lies completely within one grid box:
919	ELSE
920	tow_cd_surf(k,j,i) = dz * dtow(inot) * &
921	turb_cd_tower(inot)
922	ENDIF ! end if larger than grid box
923
924	ENDIF ! end if k == k_hub
925
926	ENDDO ! end loop over k
927
928	ENDIF ! end if inside north and south boundary of tower
929
930	ENDDO ! end loop over j
931
932	ENDIF ! end if hub inside domain + ghostpoints
933
934
935	CALL exchange_horiz( tow_cd_surf, nbgp )
936
937	!
938	!-- Calculation of the nacelle area
939	!-- CAUTION: Currently disabled due to segmentation faults on the FLOW HPC
940	!-- cluster (Oldenburg)
941	!!
942	!!-- Tabulate the points on the circle that are required in the following for
943	!!-- the calculation of the Riemann integral (node points; they are called
944	!!-- circle_points in the following):
945	!
946	! dy_int = dy / 10000.0_wp
947	!
948	! DO i_ip = 1, upper_end
949	! yvalue = dy_int * ( i_ip - 0.5_wp ) + 0.5_wp * dy !<--- segmentation fault
950	! sqrt_arg = rnac(inot)2 - ( yvalue - rcy(inot) )2 !<--- segmentation fault
951	! IF ( sqrt_arg >= 0.0_wp ) THEN
952	!!
953	!!-- bottom intersection point
954	! circle_points(1,i_ip) = rcz(inot) - SQRT( sqrt_arg )
955	!!
956	!!-- top intersection point
957	! circle_points(2,i_ip) = rcz(inot) + SQRT( sqrt_arg ) !<--- segmentation fault
958	! ELSE
959	! circle_points(:,i_ip) = -111111 !<--- segmentation fault
960	! ENDIF
961	! ENDDO
962	!
963	!
964	! DO j = nys, nyn
965	!!
966	!!-- In case that the grid box is located completely outside the nacelle
967	!!-- (y) it can automatically be stated that there is no overlap between
968	!!-- the grid box and the nacelle and consequently we can set
969	!!-- nac_cd_surf(:,j,i) = 0.0:
970	! IF ( ( j >= index_nacl(inot) ) .AND. ( j <= index_nacr(inot) ) ) THEN
971	! DO k = nzb+1, nzt
972	!!
973	!!-- In case that the grid box is located completely outside the
974	!!-- nacelle (z) it can automatically be stated that there is no
975	!!-- overlap between the grid box and the nacelle and consequently
976	!!-- we can set nac_cd_surf(k,j,i) = 0.0:
977	! IF ( ( k >= index_nacb(inot) ) .OR. &
978	! ( k <= index_nact(inot) ) ) THEN
979	!!
980	!!-- For all other cases Riemann integrals are calculated.
981	!!-- Here, the points on the circle that have been determined
982	!!-- above are used in order to calculate the overlap between the
983	!!-- gridbox and the nacelle area (area approached by 10000
984	!!-- rectangulars dz_int * dy_int):
985	! DO i_ipg = 1, 10000
986	! dz_int = dz
987	! i_ip = j * 10000 + i_ipg
988	!!
989	!!-- Determine the vertical extension dz_int of the circle
990	!!-- within the current grid box:
991	! IF ( ( circle_points(2,i_ip) < zw(k) ) .AND. & !<--- segmentation fault
992	! ( circle_points(2,i_ip) >= zw(k-1) ) ) THEN
993	! dz_int = dz_int - & !<--- segmentation fault
994	! ( zw(k) - circle_points(2,i_ip) )
995	! ENDIF
996	! IF ( ( circle_points(1,i_ip) <= zw(k) ) .AND. & !<--- segmentation fault
997	! ( circle_points(1,i_ip) > zw(k-1) ) ) THEN
998	! dz_int = dz_int - &
999	! ( circle_points(1,i_ip) - zw(k-1) )
1000	! ENDIF
1001	! IF ( zw(k-1) > circle_points(2,i_ip) ) THEN
1002	! dz_int = 0.0_wp
1003	! ENDIF
1004	! IF ( zw(k) < circle_points(1,i_ip) ) THEN
1005	! dz_int = 0.0_wp
1006	! ENDIF
1007	! IF ( ( nxlg <= i ) .AND. ( nxrg >= i ) ) THEN
1008	! nac_cd_surf(k,j,i) = nac_cd_surf(k,j,i) + & !<--- segmentation fault
1009	! dy_int * dz_int * turb_cd_nacelle(inot)
1010	! ENDIF
1011	! ENDDO
1012	! ENDIF
1013	! ENDDO
1014	! ENDIF
1015	!
1016	! ENDDO
1017	!
1018	! CALL exchange_horiz( nac_cd_surf, nbgp ) !<--- segmentation fault
1019
1020	ENDDO ! end of loop over turbines
1021
1022	tow_cd_surf = tow_cd_surf / ( dx * dy * dz ) ! Normalize tower drag
1023	nac_cd_surf = nac_cd_surf / ( dx * dy * dz ) ! Normalize nacelle drag
1024
1025	CALL wtm_read_blade_tables
1026
1027	END SUBROUTINE wtm_init
1028
1029
1030	!------------------------------------------------------------------------------!
1031	! Description:
1032	! ------------
1033	!> Read in layout of the rotor blade , the lift and drag tables
1034	!> and the distribution of lift and drag tables along the blade
1035	!------------------------------------------------------------------------------!
1036	!
1037	SUBROUTINE wtm_read_blade_tables
1038
1039
1040	IMPLICIT NONE
1041
1042	INTEGER(iwp) :: ii !< running index
1043	INTEGER(iwp) :: jj !< running index
1044
1045	INTEGER(iwp) :: ierrn !<
1046
1047	CHARACTER(200) :: chmess !< Read in string
1048
1049	INTEGER(iwp) :: dlen !< no. rows of local table
1050	INTEGER(iwp) :: dlenbl !< no. rows of cd, cl table
1051	INTEGER(iwp) :: ialpha !< table position of current alpha value
1052	INTEGER(iwp) :: iialpha !<
1053	INTEGER(iwp) :: iir !<
1054	INTEGER(iwp) :: radres !< radial resolution
1055	INTEGER(iwp) :: t1 !< no. of airfoil
1056	INTEGER(iwp) :: t2 !< no. of airfoil
1057	INTEGER(iwp) :: trow !<
1058	INTEGER(iwp) :: dlenbl_int !< no. rows of interpolated cd, cl tables
1059
1060	REAL(wp) :: alpha_attack_i !<
1061	REAL(wp) :: weight_a !<
1062	REAL(wp) :: weight_b !<
1063
1064	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: ttoint1 !<
1065	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: ttoint2 !<
1066
1067	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd_sel1 !<
1068	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd_sel2 !<
1069	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl_sel1 !<
1070	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl_sel2 !<
1071	REAL(wp), DIMENSION(:), ALLOCATABLE :: read_cl_cd !< read in var array
1072
1073	REAL(wp), DIMENSION(:), ALLOCATABLE :: alpha_attack_tab !<
1074	REAL(wp), DIMENSION(:), ALLOCATABLE :: trad1 !<
1075	REAL(wp), DIMENSION(:), ALLOCATABLE :: trad2 !<
1076	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cd_table !<
1077	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cl_table !<
1078
1079	ALLOCATE ( read_cl_cd(1:2*nairfoils+1) )
1080
1081	!
1082	!-- Read in the distribution of lift and drag tables along the blade, the
1083	!-- layout of the rotor blade and the lift and drag tables:
1084
1085	OPEN ( 201, FILE='WTM_DATA', STATUS='OLD', FORM='FORMATTED', IOSTAT=ierrn )
1086
1087	IF ( ierrn /= 0 ) THEN
1088	message_string = 'file WTM_DATA does not exist'
1089	CALL message( 'wtm_init', 'PA0???', 1, 2, 0, 6, 0 )
1090	ENDIF
1091	!
1092	!-- Read distribution table:
1093
1094	dlen = 0
1095
1096	READ ( 201, '(3/)' )
1097
1098	rloop3: DO
1099	READ ( 201, *, IOSTAT=ierrn ) chmess
1100	IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop3
1101	dlen = dlen + 1
1102	ENDDO rloop3
1103
1104	ALLOCATE( trad1(1:dlen), trad2(1:dlen), ttoint1(1:dlen), ttoint2(1:dlen))
1105
1106	DO jj = 1,dlen+1
1107	BACKSPACE ( 201, IOSTAT=ierrn )
1108	ENDDO
1109
1110	DO jj = 1,dlen
1111	READ ( 201, * ) trad1(jj), trad2(jj), ttoint1(jj), ttoint2(jj)
1112	ENDDO
1113
1114	!
1115	!-- Read layout table:
1116
1117	dlen = 0
1118
1119	READ ( 201, '(3/)')
1120
1121	rloop1: DO
1122	READ ( 201, *, IOSTAT=ierrn ) chmess
1123	IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop1
1124	dlen = dlen + 1
1125	ENDDO rloop1
1126
1127	ALLOCATE( lrd(1:dlen), ard(1:dlen), crd(1:dlen) )
1128	DO jj = 1, dlen+1
1129	BACKSPACE ( 201, IOSTAT=ierrn )
1130	ENDDO
1131	DO jj = 1, dlen
1132	READ ( 201, * ) lrd(jj), ard(jj), crd(jj)
1133	ENDDO
1134
1135	!
1136	!-- Read tables (turb_cl(alpha),turb_cd(alpha) for the different profiles:
1137
1138	dlen = 0
1139
1140	READ ( 201, '(3/)' )
1141
1142	rloop2: DO
1143	READ ( 201, *, IOSTAT=ierrn ) chmess
1144	IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop2
1145	dlen = dlen + 1
1146	ENDDO rloop2
1147
1148	ALLOCATE( alpha_attack_tab(1:dlen), turb_cl_table(1:dlen,1:nairfoils), &
1149	turb_cd_table(1:dlen,1:nairfoils) )
1150
1151	DO jj = 1,dlen+1
1152	BACKSPACE ( 201, IOSTAT=ierrn )
1153	ENDDO
1154
1155	DO jj = 1,dlen
1156	READ ( 201, * ) read_cl_cd
1157	alpha_attack_tab(jj) = read_cl_cd(1)
1158	DO ii= 1, nairfoils
1159	turb_cl_table(jj,ii) = read_cl_cd(ii*2)
1160	turb_cd_table(jj,ii) = read_cl_cd(ii*2+1)
1161	ENDDO
1162
1163	ENDDO
1164
1165	dlenbl = dlen
1166
1167	CLOSE ( 201 )
1168
1169	!
1170	!-- For each possible radial position (resolution: 0.1 m --> 630 values) and
1171	!-- each possible angle of attack (resolution: 0.01 degrees --> 36000 values!)
1172	!-- determine the lift and drag coefficient by interpolating between the
1173	!-- tabulated values of each table (interpolate to current angle of attack)
1174	!-- and between the tables (interpolate to current radial position):
1175
1176	ALLOCATE( turb_cl_sel1(0:dlenbl) )
1177	ALLOCATE( turb_cl_sel2(0:dlenbl) )
1178	ALLOCATE( turb_cd_sel1(0:dlenbl) )
1179	ALLOCATE( turb_cd_sel2(0:dlenbl) )
1180
1181	radres = INT( rr(1) * 10.0_wp ) + 1_iwp
1182	dlenbl_int = INT( 360.0_wp / accu_cl_cd_tab ) + 1_iwp
1183
1184
1185	ALLOCATE( turb_cl_tab(0:dlenbl_int,1:radres) )
1186	ALLOCATE( turb_cd_tab(0:dlenbl_int,1:radres) )
1187
1188
1189	DO iir = 1, radres ! loop over radius
1190
1191	DO iialpha = 1, dlenbl_int ! loop over angles
1192
1193	cur_r = ( iir - 1_iwp ) * 0.1_wp
1194	alpha_attack_i = -180.0_wp + REAL( iialpha-1 ) * accu_cl_cd_tab
1195	ialpha = 1
1196
1197	DO WHILE ( alpha_attack_i > alpha_attack_tab(ialpha) )
1198	ialpha = ialpha + 1
1199	ENDDO
1200	!
1201	!-- Find position in table
1202	lct = MINLOC( ABS( trad1 - cur_r ) )
1203	! lct(1) = lct(1)
1204
1205	IF ( ( trad1(lct(1)) - cur_r ) .GT. 0.0 ) THEN
1206	lct(1) = lct(1) - 1
1207	ENDIF
1208
1209	trow = lct(1)
1210	!
1211	!-- Calculate weights for interpolation
1212	weight_a = ( trad2(trow) - cur_r ) / ( trad2(trow) - trad1(trow) )
1213	weight_b = ( cur_r - trad1(trow) ) / ( trad2(trow) - trad1(trow) )
1214	t1 = ttoint1(trow)
1215	t2 = ttoint2(trow)
1216
1217	IF ( t1 .EQ. t2 ) THEN ! if both are the same, the weights are NaN
1218	weight_a = 0.5_wp ! then do interpolate in between same twice
1219	weight_b = 0.5_wp ! using 0.5 as weight
1220	ENDIF
1221
1222	IF ( t1 == 0 .AND. t2 == 0 ) THEN
1223	turb_cd_sel1 = 0.0_wp
1224	turb_cd_sel2 = 0.0_wp
1225	turb_cl_sel1 = 0.0_wp
1226	turb_cl_sel2 = 0.0_wp
1227	ELSE
1228	turb_cd_sel1 = turb_cd_table(:,t1)
1229	turb_cd_sel2 = turb_cd_table(:,t2)
1230	turb_cl_sel1 = turb_cl_table(:,t1)
1231	turb_cl_sel2 = turb_cl_table(:,t2)
1232	ENDIF
1233
1234	!
1235	!-- Interpolation of lift and drag coefficiencts on fine grid of radius
1236	!-- segments and angles of attack
1237
1238	turb_cl_tab(iialpha,iir) = ( alpha_attack_tab(ialpha) - &
1239	alpha_attack_i ) / &
1240	( alpha_attack_tab(ialpha) - &
1241	alpha_attack_tab(ialpha-1) ) * &
1242	( weight_a * turb_cl_sel1(ialpha-1) + &
1243	weight_b * turb_cl_sel2(ialpha-1) ) +&
1244	( alpha_attack_i - &
1245	alpha_attack_tab(ialpha-1) ) / &
1246	( alpha_attack_tab(ialpha) - &
1247	alpha_attack_tab(ialpha-1) ) * &
1248	( weight_a * turb_cl_sel1(ialpha) + &
1249	weight_b * turb_cl_sel2(ialpha) )
1250	turb_cd_tab(iialpha,iir) = ( alpha_attack_tab(ialpha) - &
1251	alpha_attack_i ) / &
1252	( alpha_attack_tab(ialpha) - &
1253	alpha_attack_tab(ialpha-1) ) * &
1254	( weight_a * turb_cd_sel1(ialpha-1) + &
1255	weight_b * turb_cd_sel2(ialpha-1) ) +&
1256	( alpha_attack_i - &
1257	alpha_attack_tab(ialpha-1) ) / &
1258	( alpha_attack_tab(ialpha) - &
1259	alpha_attack_tab(ialpha-1) ) * &
1260	( weight_a * turb_cd_sel1(ialpha) + &
1261	weight_b * turb_cd_sel2(ialpha) )
1262
1263	ENDDO ! end loop over angles of attack
1264
1265	ENDDO ! end loop over radius
1266
1267	END SUBROUTINE wtm_read_blade_tables
1268
1269
1270	!------------------------------------------------------------------------------!
1271	! Description:
1272	! ------------
1273	!> The projection matrix for the coordinate system of therotor disc in respect
1274	!> to the yaw and tilt angle of the rotor is calculated
1275	!------------------------------------------------------------------------------!
1276	SUBROUTINE wtm_rotate_rotor( inot )
1277
1278
1279	IMPLICIT NONE
1280
1281	INTEGER(iwp) :: inot
1282	!
1283	!-- Calculation of the rotation matrix for the application of the tilt to
1284	!-- the rotors
1285	rot_eigen_rad(1) = SIN( phi_yaw(inot) ) ! x-component of the radial eigenvector
1286	rot_eigen_rad(2) = COS( phi_yaw(inot) ) ! y-component of the radial eigenvector
1287	rot_eigen_rad(3) = 0.0_wp ! z-component of the radial eigenvector
1288
1289	rot_eigen_azi(1) = 0.0_wp ! x-component of the azimuth eigenvector
1290	rot_eigen_azi(2) = 0.0_wp ! y-component of the azimuth eigenvector
1291	rot_eigen_azi(3) = 1.0_wp ! z-component of the azimuth eigenvector
1292
1293	rot_eigen_nor(1) = COS( phi_yaw(inot) ) ! x-component of the normal eigenvector
1294	rot_eigen_nor(2) = -SIN( phi_yaw(inot) ) ! y-component of the normal eigenvector
1295	rot_eigen_nor(3) = 0.0_wp ! z-component of the normal eigenvector
1296
1297	!
1298	!-- Calculation of the coordinate transformation matrix to apply a tilt to
1299	!-- the rotor. If tilt = 0, rot_coord_trans is a unit matrix.
1300
1301	rot_coord_trans(inot,1,1) = rot_eigen_rad(1)*2 &
1302	( 1.0_wp - COS( tilt ) ) + COS( tilt )
1303	rot_coord_trans(inot,1,2) = rot_eigen_rad(1) * rot_eigen_rad(2) * &
1304	( 1.0_wp - COS( tilt ) ) - &
1305	rot_eigen_rad(3) * SIN( tilt )
1306	rot_coord_trans(inot,1,3) = rot_eigen_rad(1) * rot_eigen_rad(3) * &
1307	( 1.0_wp - COS( tilt ) ) + &
1308	rot_eigen_rad(2) * SIN( tilt )
1309	rot_coord_trans(inot,2,1) = rot_eigen_rad(2) * rot_eigen_rad(1) * &
1310	( 1.0_wp - COS( tilt ) ) + &
1311	rot_eigen_rad(3) * SIN( tilt )
1312	rot_coord_trans(inot,2,2) = rot_eigen_rad(2)*2 &
1313	( 1.0_wp - COS( tilt ) ) + COS( tilt )
1314	rot_coord_trans(inot,2,3) = rot_eigen_rad(2) * rot_eigen_rad(3) * &
1315	( 1.0_wp - COS( tilt ) ) - &
1316	rot_eigen_rad(1) * SIN( tilt )
1317	rot_coord_trans(inot,3,1) = rot_eigen_rad(3) * rot_eigen_rad(1) * &
1318	( 1.0_wp - COS( tilt ) ) - &
1319	rot_eigen_rad(2) * SIN( tilt )
1320	rot_coord_trans(inot,3,2) = rot_eigen_rad(3) * rot_eigen_rad(2) * &
1321	( 1.0_wp - COS( tilt ) ) + &
1322	rot_eigen_rad(1) * SIN( tilt )
1323	rot_coord_trans(inot,3,3) = rot_eigen_rad(3)*2 &
1324	( 1.0_wp - COS( tilt ) ) + COS( tilt )
1325
1326	!
1327	!-- Vectors for the Transformation of forces from the rotor's spheric
1328	!-- coordinate system to the cartesian coordinate system
1329	rotx(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_nor )
1330	roty(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_rad )
1331	rotz(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_azi )
1332
1333	END SUBROUTINE wtm_rotate_rotor
1334
1335
1336	!------------------------------------------------------------------------------!
1337	! Description:
1338	! ------------
1339	!> Calculation of the forces generated by the wind turbine
1340	!------------------------------------------------------------------------------!
1341	SUBROUTINE wtm_forces
1342
1343
1344	IMPLICIT NONE
1345
1346	CHARACTER (LEN=2) :: turbine_id
1347
1348	INTEGER(iwp) :: i, j, k !< loop indices
1349	INTEGER(iwp) :: inot !< turbine loop index (turbine id)
1350	INTEGER(iwp) :: iialpha, iir !<
1351	INTEGER(iwp) :: rseg, rseg_int !<
1352	INTEGER(iwp) :: ring, ring_int !<
1353	INTEGER(iwp) :: ii, jj, kk !<
1354
1355	REAL(wp) :: sin_rot, cos_rot !<
1356	REAL(wp) :: sin_yaw, cos_yaw !<
1357
1358	REAL(wp) :: aa, bb, cc, dd !< interpolation distances
1359	REAL(wp) :: gg !< interpolation volume var
1360
1361	REAL(wp) :: dist_u_3d, dist_v_3d, dist_w_3d !< smearing distances
1362
1363
1364	!
1365	! Variables for pitch control
1366	REAL(wp) :: torque_max=0.0_wp
1367	LOGICAL :: pitch_sw=.FALSE.
1368
1369	INTEGER(iwp), DIMENSION(1) :: lct=0
1370	REAL(wp), DIMENSION(1) :: rad_d=0.0_wp
1371
1372
1373	CALL cpu_log( log_point_s(61), 'wtm_forces', 'start' )
1374
1375
1376	IF ( simulated_time >= time_turbine_on ) THEN
1377
1378	!
1379	!-- Set forces to zero for each new time step:
1380	thrust(:,:,:) = 0.0_wp
1381	torque_y(:,:,:) = 0.0_wp
1382	torque_z(:,:,:) = 0.0_wp
1383	torque_total(:) = 0.0_wp
1384	rot_tend_x(:,:,:) = 0.0_wp
1385	rot_tend_y(:,:,:) = 0.0_wp
1386	rot_tend_z(:,:,:) = 0.0_wp
1387	thrust_rotor(:) = 0.0_wp
1388	!
1389	!-- Loop over number of turbines:
1390	DO inot = 1, nturbines
1391
1392	cos_yaw = COS(phi_yaw(inot))
1393	sin_yaw = SIN(phi_yaw(inot))
1394	!
1395	!-- Loop over rings of each turbine:
1396	DO ring = 1, nrings(inot)
1397
1398	thrust_seg(:) = 0.0_wp
1399	torque_seg_y(:) = 0.0_wp
1400	torque_seg_z(:) = 0.0_wp
1401	!
1402	!-- Determine distance between each ring (center) and the hub:
1403	cur_r = (ring - 0.5_wp) * delta_r(inot)
1404
1405	!
1406	!-- Loop over segments of each ring of each turbine:
1407	DO rseg = 1, nsegs(ring,inot)
1408	!
1409	!-- !-----------------------------------------------------------!
1410	!-- !-- Determine coordinates of the ring segments --!
1411	!-- !-----------------------------------------------------------!
1412	!
1413	!-- Determine angle of ring segment towards zero degree angle of
1414	!-- rotor system (at zero degree rotor direction vectors aligned
1415	!-- with y-axis):
1416	phi_rotor = rseg * 2.0_wp * pi / nsegs(ring,inot)
1417	cos_rot = COS( phi_rotor )
1418	sin_rot = SIN( phi_rotor )
1419
1420	!-- Now the direction vectors can be determined with respect to
1421	!-- the yaw and tilt angle:
1422	re(1) = cos_rot * sin_yaw
1423	re(2) = cos_rot * cos_yaw
1424	re(3) = sin_rot
1425
1426	rote = MATMUL( rot_coord_trans(inot,:,:), re )
1427	!
1428	!-- Coordinates of the single segments (center points):
1429	rbx(ring,rseg) = rcx(inot) + cur_r * rote(1)
1430	rby(ring,rseg) = rcy(inot) + cur_r * rote(2)
1431	rbz(ring,rseg) = rcz(inot) + cur_r * rote(3)
1432
1433	!-- !-----------------------------------------------------------!
1434	!-- !-- Interpolation of the velocity components from the --!
1435	!-- !-- cartesian grid point to the coordinates of each ring --!
1436	!-- !-- segment (follows a method used in the particle model) --!
1437	!-- !-----------------------------------------------------------!
1438
1439	u_int(inot,ring,rseg) = 0.0_wp
1440	u_int_1_l(inot,ring,rseg) = 0.0_wp
1441
1442	v_int(inot,ring,rseg) = 0.0_wp
1443	v_int_1_l(inot,ring,rseg) = 0.0_wp
1444
1445	w_int(inot,ring,rseg) = 0.0_wp
1446	w_int_1_l(inot,ring,rseg) = 0.0_wp
1447
1448	!
1449	!-- Interpolation of the u-component:
1450
1451	ii = rbx(ring,rseg) * ddx
1452	jj = ( rby(ring,rseg) - 0.5_wp * dy ) * ddy
1453	kk = ( rbz(ring,rseg) - 0.5_wp * dz ) / dz
1454	!
1455	!-- Interpolate only if all required information is available on
1456	!-- the current PE:
1457	IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN
1458	IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN
1459
1460	aa = ( ( ii + 1 ) * dx - rbx(ring,rseg) ) * &
1461	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1462	bb = ( rbx(ring,rseg) - ii * dx ) * &
1463	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1464	cc = ( ( ii+1 ) * dx - rbx(ring,rseg) ) * &
1465	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1466	dd = ( rbx(ring,rseg) - ii * dx ) * &
1467	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1468	gg = dx * dy
1469
1470	u_int_l = ( aa * u(kk,jj,ii) + &
1471	bb * u(kk,jj,ii+1) + &
1472	cc * u(kk,jj+1,ii) + &
1473	dd * u(kk,jj+1,ii+1) &
1474	) / gg
1475
1476	u_int_u = ( aa * u(kk+1,jj,ii) + &
1477	bb * u(kk+1,jj,ii+1) + &
1478	cc * u(kk+1,jj+1,ii) + &
1479	dd * u(kk+1,jj+1,ii+1) &
1480	) / gg
1481
1482	u_int_1_l(inot,ring,rseg) = u_int_l + &
1483	( rbz(ring,rseg) - zu(kk) ) / dz * &
1484	( u_int_u - u_int_l )
1485
1486	ELSE
1487	u_int_1_l(inot,ring,rseg) = 0.0_wp
1488	ENDIF
1489	ELSE
1490	u_int_1_l(inot,ring,rseg) = 0.0_wp
1491	ENDIF
1492
1493
1494	!
1495	!-- Interpolation of the v-component:
1496	ii = ( rbx(ring,rseg) - 0.5_wp * dx ) * ddx
1497	jj = rby(ring,rseg) * ddy
1498	kk = ( rbz(ring,rseg) + 0.5_wp * dz ) / dz
1499	!
1500	!-- Interpolate only if all required information is available on
1501	!-- the current PE:
1502	IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN
1503	IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN
1504
1505	aa = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1506	( ( jj + 1 ) * dy - rby(ring,rseg) )
1507	bb = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1508	( ( jj + 1 ) * dy - rby(ring,rseg) )
1509	cc = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1510	( rby(ring,rseg) - jj * dy )
1511	dd = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1512	( rby(ring,rseg) - jj * dy )
1513	gg = dx * dy
1514
1515	v_int_l = ( aa * v(kk,jj,ii) + &
1516	bb * v(kk,jj,ii+1) + &
1517	cc * v(kk,jj+1,ii) + &
1518	dd * v(kk,jj+1,ii+1) &
1519	) / gg
1520
1521	v_int_u = ( aa * v(kk+1,jj,ii) + &
1522	bb * v(kk+1,jj,ii+1) + &
1523	cc * v(kk+1,jj+1,ii) + &
1524	dd * v(kk+1,jj+1,ii+1) &
1525	) / gg
1526
1527	v_int_1_l(inot,ring,rseg) = v_int_l + &
1528	( rbz(ring,rseg) - zu(kk) ) / dz * &
1529	( v_int_u - v_int_l )
1530
1531	ELSE
1532	v_int_1_l(inot,ring,rseg) = 0.0_wp
1533	ENDIF
1534	ELSE
1535	v_int_1_l(inot,ring,rseg) = 0.0_wp
1536	ENDIF
1537
1538
1539	!
1540	!-- Interpolation of the w-component:
1541	ii = ( rbx(ring,rseg) - 0.5_wp * dx ) * ddx
1542	jj = ( rby(ring,rseg) - 0.5_wp * dy ) * ddy
1543	kk = rbz(ring,rseg) / dz
1544	!
1545	!-- Interpolate only if all required information is available on
1546	!-- the current PE:
1547	IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN
1548	IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN
1549
1550	aa = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1551	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1552	bb = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1553	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1554	cc = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1555	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1556	dd = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1557	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1558	gg = dx * dy
1559
1560	w_int_l = ( aa * w(kk,jj,ii) + &
1561	bb * w(kk,jj,ii+1) + &
1562	cc * w(kk,jj+1,ii) + &
1563	dd * w(kk,jj+1,ii+1) &
1564	) / gg
1565
1566	w_int_u = ( aa * w(kk+1,jj,ii) + &
1567	bb * w(kk+1,jj,ii+1) + &
1568	cc * w(kk+1,jj+1,ii) + &
1569	dd * w(kk+1,jj+1,ii+1) &
1570	) / gg
1571
1572	w_int_1_l(inot,ring,rseg) = w_int_l + &
1573	( rbz(ring,rseg) - zw(kk) ) / dz * &
1574	( w_int_u - w_int_l )
1575	ELSE
1576	w_int_1_l(inot,ring,rseg) = 0.0_wp
1577	ENDIF
1578	ELSE
1579	w_int_1_l(inot,ring,rseg) = 0.0_wp
1580	ENDIF
1581
1582	ENDDO
1583	ENDDO
1584
1585	ENDDO
1586
1587	!
1588	!-- Exchange between PEs (information required on each PE):
1589	#if defined( __parallel )
1590	CALL MPI_ALLREDUCE( u_int_1_l, u_int, nturbines * MAXVAL(nrings) * &
1591	MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr )
1592	CALL MPI_ALLREDUCE( v_int_1_l, v_int, nturbines * MAXVAL(nrings) * &
1593	MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr )
1594	CALL MPI_ALLREDUCE( w_int_1_l, w_int, nturbines * MAXVAL(nrings) * &
1595	MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr )
1596	#else
1597	u_int = u_int_1_l
1598	v_int = v_int_1_l
1599	w_int = w_int_1_l
1600	#endif
1601
1602
1603	!
1604	!-- Loop over number of turbines:
1605
1606	DO inot = 1, nturbines
1607	pit_loop: DO
1608
1609	IF ( pitch_sw ) THEN
1610	torque_total(inot) = 0.0_wp
1611	thrust_rotor(inot) = 0.0_wp
1612	pitch_add(inot) = pitch_add(inot) + 0.25_wp
1613	! IF ( myid == 0 ) PRINT*, 'Pitch', inot, pitch_add(inot)
1614	ELSE
1615	cos_yaw = COS(phi_yaw(inot))
1616	sin_yaw = SIN(phi_yaw(inot))
1617	IF ( pitch_control ) THEN
1618	pitch_add(inot) = MAX(pitch_add_old(inot) - pitch_rate * &
1619	dt_3d , 0.0_wp )
1620	ENDIF
1621	ENDIF
1622
1623	!
1624	!-- Loop over rings of each turbine:
1625	DO ring = 1, nrings(inot)
1626	!
1627	!-- Determine distance between each ring (center) and the hub:
1628	cur_r = (ring - 0.5_wp) * delta_r(inot)
1629	!
1630	!-- Loop over segments of each ring of each turbine:
1631	DO rseg = 1, nsegs(ring,inot)
1632	!
1633	!-- Determine angle of ring segment towards zero degree angle of
1634	!-- rotor system (at zero degree rotor direction vectors aligned
1635	!-- with y-axis):
1636	phi_rotor = rseg * 2.0_wp * pi / nsegs(ring,inot)
1637	cos_rot = COS(phi_rotor)
1638	sin_rot = SIN(phi_rotor)
1639	!
1640	!-- Now the direction vectors can be determined with respect to
1641	!-- the yaw and tilt angle:
1642	re(1) = cos_rot * sin_yaw
1643	re(2) = cos_rot * cos_yaw
1644	re(3) = sin_rot
1645
1646	! The current unit vector in azimuthal direction:
1647	rea(1) = - sin_rot * sin_yaw
1648	rea(2) = - sin_rot * cos_yaw
1649	rea(3) = cos_rot
1650
1651	!
1652	!-- To respect the yawing angle for the calculations of
1653	!-- velocities and forces the unit vectors perpendicular to the
1654	!-- rotor area in direction of the positive yaw angle are defined:
1655	ren(1) = cos_yaw
1656	ren(2) = - sin_yaw
1657	ren(3) = 0.0_wp
1658	!
1659	!-- Multiplication with the coordinate transformation matrix
1660	!-- gives the final unit vector with consideration of the rotor
1661	!-- tilt:
1662	rote = MATMUL( rot_coord_trans(inot,:,:), re )
1663	rota = MATMUL( rot_coord_trans(inot,:,:), rea )
1664	rotn = MATMUL( rot_coord_trans(inot,:,:), ren )
1665	!
1666	!-- Coordinates of the single segments (center points):
1667	rbx(ring,rseg) = rcx(inot) + cur_r * rote(1)
1668
1669	rby(ring,rseg) = rcy(inot) + cur_r * rote(2)
1670
1671	rbz(ring,rseg) = rcz(inot) + cur_r * rote(3)
1672
1673	!
1674	!-- !-----------------------------------------------------------!
1675	!-- !-- Calculation of various angles and relative velocities --!
1676	!-- !-----------------------------------------------------------!
1677	!
1678	!-- In the following the 3D-velocity field is projected its
1679	!-- components perpedicular and parallel to the rotor area
1680	!-- The calculation of forces will be done in the rotor-
1681	!-- coordinates y' and z.
1682	!-- The yaw angle will be reintroduced when the force is applied
1683	!-- on the hydrodynamic equations
1684	!
1685	!-- Projection of the xy-velocities relative to the rotor area
1686	!
1687	!-- Velocity perpendicular to the rotor area:
1688	u_rot = u_int(inot,ring,rseg)*rotn(1) + &
1689	v_int(inot,ring,rseg)*rotn(2) + &
1690	w_int(inot,ring,rseg)*rotn(3)
1691	!
1692	!-- Projection of the 3D-velocity vector in the azimuthal
1693	!-- direction:
1694	vtheta(rseg) = rota(1) * u_int(inot,ring,rseg) + &
1695	rota(2) * v_int(inot,ring,rseg) + &
1696	rota(3) * w_int(inot,ring,rseg)
1697	!
1698	!-- Determination of the angle phi_rel between the rotor plane
1699	!-- and the direction of the flow relative to the rotor:
1700
1701	phi_rel(rseg) = ATAN( u_rot / &
1702	( omega_rot(inot) * cur_r - &
1703	vtheta(rseg) ) )
1704
1705	!
1706	!-- Interpolation of the local pitch angle from tabulated values
1707	!-- to the current radial position:
1708
1709	lct=minloc(ABS(cur_r-lrd))
1710	rad_d=cur_r-lrd(lct)
1711
1712	IF (cur_r == 0.0_wp) THEN
1713	alpha_attack(rseg) = 0.0_wp
1714	ELSE IF (cur_r >= lrd(size(ard))) THEN
1715	alpha_attack(rseg) = ( ard(size(ard)) + &
1716	ard(size(ard)-1) ) / 2.0_wp
1717	ELSE
1718	alpha_attack(rseg) = ( ard(lct(1)) * &
1719	( ( lrd(lct(1)+1) - cur_r ) / &
1720	( lrd(lct(1)+1) - lrd(lct(1)) ) &
1721	) ) + ( ard(lct(1)+1) * &
1722	( ( cur_r - lrd(lct(1)) ) / &
1723	( lrd(lct(1)+1) - lrd(lct(1)) ) ) )
1724	ENDIF
1725
1726	!
1727	!-- In Fortran radian instead of degree is used as unit for all
1728	!-- angles. Therefore, a transformation from angles given in
1729	!-- degree to angles given in radian is necessary here:
1730	alpha_attack(rseg) = alpha_attack(rseg) * &
1731	( (2.0_wp*pi) / 360.0_wp )
1732	!
1733	!-- Substraction of the local pitch angle to obtain the local
1734	!-- angle of attack:
1735	alpha_attack(rseg) = phi_rel(rseg) - alpha_attack(rseg)
1736	!
1737	!-- Preliminary transformation back from angles given in radian
1738	!-- to angles given in degree:
1739	alpha_attack(rseg) = alpha_attack(rseg) * &
1740	( 360.0_wp / (2.0_wp*pi) )
1741	!
1742	!-- Correct with collective pitch angle:
1743	alpha_attack = alpha_attack - pitch_add(inot)
1744
1745	!
1746	!-- Determination of the magnitude of the flow velocity relative
1747	!-- to the rotor:
1748	vrel(rseg) = SQRT( u_rot**2 + &
1749	( omega_rot(inot) * cur_r - &
1750	vtheta(rseg) )**2 )
1751
1752	!
1753	!-- !-----------------------------------------------------------!
1754	!-- !-- Interpolation of chord as well as lift and drag --!
1755	!-- !-- coefficients from tabulated values --!
1756	!-- !-----------------------------------------------------------!
1757
1758	!
1759	!-- Interpolation of the chord_length from tabulated values to
1760	!-- the current radial position:
1761
1762	IF (cur_r == 0.0_wp) THEN
1763	chord(rseg) = 0.0_wp
1764	ELSE IF (cur_r >= lrd(size(crd))) THEN
1765	chord(rseg) = (crd(size(crd)) + ard(size(crd)-1)) / 2.0_wp
1766	ELSE
1767	chord(rseg) = ( crd(lct(1)) * &
1768	( ( lrd(lct(1)+1) - cur_r ) / &
1769	( lrd(lct(1)+1) - lrd(lct(1)) ) ) ) + &
1770	( crd(lct(1)+1) * &
1771	( ( cur_r-lrd(lct(1)) ) / &
1772	( lrd(lct(1)+1) - lrd(lct(1)) ) ) )
1773	ENDIF
1774
1775	!
1776	!-- Determine index of current angle of attack, needed for
1777	!-- finding the appropriate interpolated values of the lift and
1778	!-- drag coefficients (-180.0 degrees = 0, +180.0 degrees = 36000,
1779	!-- so one index every 0.01 degrees):
1780	iialpha = CEILING( ( alpha_attack(rseg) + 180.0_wp ) &
1781	* ( 1.0_wp / accu_cl_cd_tab ) )
1782	!
1783	!-- Determine index of current radial position, needed for
1784	!-- finding the appropriate interpolated values of the lift and
1785	!-- drag coefficients (one index every 0.1 m):
1786	iir = CEILING( cur_r * 10.0_wp )
1787	!
1788	!-- Read in interpolated values of the lift and drag coefficients
1789	!-- for the current radial position and angle of attack:
1790	turb_cl(rseg) = turb_cl_tab(iialpha,iir)
1791	turb_cd(rseg) = turb_cd_tab(iialpha,iir)
1792
1793	!
1794	!-- Final transformation back from angles given in degree to
1795	!-- angles given in radian:
1796	alpha_attack(rseg) = alpha_attack(rseg) * &
1797	( (2.0_wp*pi) / 360.0_wp )
1798
1799	!
1800	!-- !-----------------------------------------------------!
1801	!-- !-- Calculation of the forces --!
1802	!-- !-----------------------------------------------------!
1803
1804	!
1805	!-- Calculate the pre_factor for the thrust and torque forces:
1806
1807	pre_factor = 0.5_wp * (vrel(rseg)*2) 3.0_wp * &
1808	chord(rseg) * delta_r(inot) / nsegs(ring,inot)
1809
1810	!
1811	!-- Calculate the thrust force (x-component of the total force)
1812	!-- for each ring segment:
1813	thrust_seg(rseg) = pre_factor * &
1814	( turb_cl(rseg) * COS(phi_rel(rseg)) + &
1815	turb_cd(rseg) * SIN(phi_rel(rseg)) )
1816
1817	!
1818	!-- Determination of the second of the additional forces acting
1819	!-- on the flow in the azimuthal direction: force vector as basis
1820	!-- for torque (torque itself would be the vector product of the
1821	!-- radius vector and the force vector):
1822	torque_seg = pre_factor * &
1823	( turb_cl(rseg) * SIN(phi_rel(rseg)) - &
1824	turb_cd(rseg) * COS(phi_rel(rseg)) )
1825	!
1826	!-- Decomposition of the force vector into two parts:
1827	!-- One acting along the y-direction and one acting along the
1828	!-- z-direction of the rotor coordinate system:
1829
1830	torque_seg_y(rseg) = -torque_seg * sin_rot
1831	torque_seg_z(rseg) = torque_seg * cos_rot
1832
1833	!
1834	!-- Add the segment thrust to the thrust of the whole rotor
1835	thrust_rotor(inot) = thrust_rotor(inot) + &
1836	thrust_seg(rseg)
1837
1838
1839	torque_total(inot) = torque_total(inot) + (torque_seg * cur_r)
1840
1841	ENDDO !-- end of loop over ring segments
1842
1843	!
1844	!-- Restore the forces into arrays containing all the segments of
1845	!-- each ring:
1846	thrust_ring(ring,:) = thrust_seg(:)
1847	torque_ring_y(ring,:) = torque_seg_y(:)
1848	torque_ring_z(ring,:) = torque_seg_z(:)
1849
1850
1851	ENDDO !-- end of loop over rings
1852
1853
1854	CALL cpu_log( log_point_s(62), 'wtm_controller', 'start' )
1855
1856
1857	IF ( speed_control ) THEN
1858	!
1859	!-- Calculation of the current generator speed for rotor speed control
1860
1861	!
1862	!-- The acceleration of the rotor speed is calculated from
1863	!-- the force balance of the accelerating torque
1864	!-- and the torque of the rotating rotor and generator
1865	om_rate = ( torque_total(inot) * air_dens * gear_eff - &
1866	gear_ratio * torque_gen_old(inot) ) / &
1867	( inertia_rot + &
1868	gear_ratio * gear_ratio * inertia_gen ) * dt_3d
1869
1870	!
1871	!-- The generator speed is given by the product of gear gear_ratio
1872	!-- and rotor speed
1873	omega_gen(inot) = gear_ratio * ( omega_rot(inot) + om_rate )
1874
1875	ENDIF
1876
1877	IF ( pitch_control ) THEN
1878
1879	!
1880	!-- If the current generator speed is above rated, the pitch is not
1881	!-- saturated and the change from the last time step is within the
1882	!-- maximum pitch rate, then the pitch loop is repeated with a pitch
1883	!-- gain
1884	IF ( ( omega_gen(inot) > rated_genspeed ) .AND. &
1885	( pitch_add(inot) < 25.0_wp ) .AND. &
1886	( pitch_add(inot) < pitch_add_old(inot) + &
1887	pitch_rate * dt_3d ) ) THEN
1888	pitch_sw = .TRUE.
1889	!
1890	!-- Go back to beginning of pit_loop
1891	CYCLE pit_loop
1892	ENDIF
1893
1894	!
1895	!-- The current pitch is saved for the next time step
1896	pitch_add_old(inot) = pitch_add(inot)
1897	pitch_sw = .FALSE.
1898	ENDIF
1899	EXIT pit_loop
1900	ENDDO pit_loop ! Recursive pitch control loop
1901
1902
1903	!
1904	!-- Call the rotor speed controller
1905
1906	IF ( speed_control ) THEN
1907	!
1908	!-- Find processor at i_hub, j_hub
1909	IF ( ( nxl <= i_hub(inot) ) .AND. ( nxr >= i_hub(inot) ) ) &
1910	THEN
1911	IF ( ( nys <= j_hub(inot) ) .AND. ( nyn >= j_hub(inot) ) )&
1912	THEN
1913	CALL wtm_speed_control( inot )
1914	ENDIF
1915	ENDIF
1916
1917	ENDIF
1918
1919
1920	CALL cpu_log( log_point_s(62), 'wtm_controller', 'stop' )
1921
1922	CALL cpu_log( log_point_s(63), 'wtm_smearing', 'start' )
1923
1924
1925	!-- !-----------------------------------------------------------------!
1926	!-- !-- Regularization kernel --!
1927	!-- !-- Smearing of the forces and interpolation to cartesian grid --!
1928	!-- !-----------------------------------------------------------------!
1929	!
1930	!-- The aerodynamic blade forces need to be distributed smoothly on
1931	!-- several mesh points in order to avoid singular behaviour
1932	!
1933	!-- Summation over sum of weighted forces. The weighting factor
1934	!-- (calculated in user_init) includes information on the distance
1935	!-- between the center of the grid cell and the rotor segment under
1936	!-- consideration
1937	!
1938	!-- To save computing time, apply smearing only for the relevant part
1939	!-- of the model domain:
1940	!
1941	!--
1942	!-- Calculation of the boundaries:
1943	i_smear(inot) = CEILING( ( rr(inot) * ABS( roty(inot,1) ) + &
1944	eps_min ) / dx )
1945	j_smear(inot) = CEILING( ( rr(inot) * ABS( roty(inot,2) ) + &
1946	eps_min ) / dy )
1947
1948	DO i = MAX( nxl, i_hub(inot) - i_smear(inot) ), &
1949	MIN( nxr, i_hub(inot) + i_smear(inot) )
1950	DO j = MAX( nys, j_hub(inot) - j_smear(inot) ), &
1951	MIN( nyn, j_hub(inot) + j_smear(inot) )
1952	DO k = MAX( nzb_u_inner(j,i)+1, k_hub(inot) - k_smear(inot) ), &
1953	k_hub(inot) + k_smear(inot)
1954	DO ring = 1, nrings(inot)
1955	DO rseg = 1, nsegs(ring,inot)
1956	!
1957	!-- Determine the square of the distance between the
1958	!-- current grid point and each rotor area segment:
1959	dist_u_3d = ( i * dx - rbx(ring,rseg) )**2 + &
1960	( j * dy + 0.5_wp * dy - rby(ring,rseg) )**2 + &
1961	( k * dz - 0.5_wp * dz - rbz(ring,rseg) )**2
1962	dist_v_3d = ( i * dx + 0.5_wp * dx - rbx(ring,rseg) )**2 + &
1963	( j * dy - rby(ring,rseg) )**2 + &
1964	( k * dz - 0.5_wp * dz - rbz(ring,rseg) )**2
1965	dist_w_3d = ( i * dx + 0.5_wp * dx - rbx(ring,rseg) )**2 + &
1966	( j * dy + 0.5_wp * dy - rby(ring,rseg) )**2 + &
1967	( k * dz - rbz(ring,rseg) )**2
1968
1969	!
1970	!-- 3D-smearing of the forces with a polynomial function
1971	!-- (much faster than the old Gaussian function), using
1972	!-- some parameters that have been calculated in user_init.
1973	!-- The function is only similar to Gaussian function for
1974	!-- squared distances <= eps_min2:
1975	IF ( dist_u_3d <= eps_min2 ) THEN
1976	thrust(k,j,i) = thrust(k,j,i) + &
1977	thrust_ring(ring,rseg) * &
1978	( ( pol_a * dist_u_3d - pol_b ) * &
1979	dist_u_3d + 1.0_wp ) * eps_factor
1980	ENDIF
1981	IF ( dist_v_3d <= eps_min2 ) THEN
1982	torque_y(k,j,i) = torque_y(k,j,i) + &
1983	torque_ring_y(ring,rseg) * &
1984	( ( pol_a * dist_v_3d - pol_b ) *&
1985	dist_v_3d + 1.0_wp ) * eps_factor
1986	ENDIF
1987	IF ( dist_w_3d <= eps_min2 ) THEN
1988	torque_z(k,j,i) = torque_z(k,j,i) + &
1989	torque_ring_z(ring,rseg) * &
1990	( ( pol_a * dist_w_3d - pol_b ) *&
1991	dist_w_3d + 1.0_wp ) * eps_factor
1992	ENDIF
1993
1994	ENDDO ! End of loop over rseg
1995	ENDDO ! End of loop over ring
1996
1997	!
1998	!-- Rotation of force components:
1999	rot_tend_x(k,j,i) = rot_tend_x(k,j,i) + &
2000	thrust(k,j,i)*rotx(inot,1) + &
2001	torque_y(k,j,i)*roty(inot,1) + &
2002	torque_z(k,j,i)*rotz(inot,1)
2003
2004	rot_tend_y(k,j,i) = rot_tend_y(k,j,i) + &
2005	thrust(k,j,i)*rotx(inot,2) + &
2006	torque_y(k,j,i)*roty(inot,2) + &
2007	torque_z(k,j,i)*rotz(inot,2)
2008
2009	rot_tend_z(k,j,i) = rot_tend_z(k,j,i) + &
2010	thrust(k,j,i)*rotx(inot,3) + &
2011	torque_y(k,j,i)*roty(inot,3) + &
2012	torque_z(k,j,i)*rotz(inot,3)
2013
2014	ENDDO ! End of loop over k
2015	ENDDO ! End of loop over j
2016	ENDDO ! End of loop over i
2017
2018	CALL cpu_log( log_point_s(63), 'wtm_smearing', 'stop' )
2019
2020	ENDDO !-- end of loop over turbines
2021
2022
2023	IF ( yaw_control ) THEN
2024	!
2025	!-- Allocate arrays for yaw control at first call
2026	!-- Can't be allocated before dt_3d is set
2027	IF ( start_up ) THEN
2028	WDLON = NINT( 30.0_wp / dt_3d ) ! 30s running mean array
2029	ALLOCATE( wd30(1:nturbines,1:WDLON) )
2030	wd30 = 999.0_wp ! Set to dummy value
2031	ALLOCATE( wd30_l(1:WDLON) )
2032
2033	WDSHO = NINT( 2.0_wp / dt_3d ) ! 2s running mean array
2034	ALLOCATE( wd2(1:nturbines,1:WDSHO) )
2035	wd2 = 999.0_wp ! Set to dummy value
2036	ALLOCATE( wd2_l(1:WDSHO) )
2037	start_up = .FALSE.
2038	ENDIF
2039
2040	!
2041	!-- Calculate the inflow wind speed
2042	!--
2043	!-- Loop over number of turbines:
2044	DO inot = 1, nturbines
2045	!
2046	!-- Find processor at i_hub, j_hub
2047	IF ( ( nxl <= i_hub(inot) ) .AND. ( nxr >= i_hub(inot) ) ) &
2048	THEN
2049	IF ( ( nys <= j_hub(inot) ) .AND. ( nyn >= j_hub(inot) ) )&
2050	THEN
2051
2052	u_inflow_l(inot) = u(k_hub(inot),j_hub(inot),i_hub(inot))
2053
2054	wdir_l(inot) = -1.0_wp * ATAN2( &
2055	0.5_wp * ( v(k_hub(inot),j_hub(inot),i_hub(inot)+1) + &
2056	v(k_hub(inot),j_hub(inot),i_hub(inot)) ) , &
2057	0.5_wp * ( u(k_hub(inot),j_hub(inot)+1,i_hub(inot)) + &
2058	u(k_hub(inot),j_hub(inot),i_hub(inot)) ) )
2059
2060	CALL wtm_yawcontrol( inot )
2061
2062	phi_yaw_l(inot) = phi_yaw(inot)
2063
2064	ENDIF
2065	ENDIF
2066
2067	ENDDO !-- end of loop over turbines
2068
2069	!
2070	!-- Transfer of information to the other cpus
2071	#if defined( __parallel )
2072	CALL MPI_ALLREDUCE( u_inflow_l, u_inflow, nturbines, MPI_REAL, &
2073	MPI_SUM, comm2d, ierr )
2074	CALL MPI_ALLREDUCE( wdir_l, wdir, nturbines, MPI_REAL, MPI_SUM, &
2075	comm2d, ierr )
2076	CALL MPI_ALLREDUCE( phi_yaw_l, phi_yaw, nturbines, MPI_REAL, &
2077	MPI_SUM, comm2d, ierr )
2078	#else
2079	u_inflow = u_inflow_l
2080	wdir = wdir_l
2081	phi_yaw = phi_yaw_l
2082
2083
2084	#endif
2085	DO inot = 1, nturbines
2086	!
2087	!-- Update rotor orientation
2088	CALL wtm_rotate_rotor( inot )
2089
2090	ENDDO ! End of loop over turbines
2091
2092	END IF
2093
2094	IF ( speed_control ) THEN
2095	!
2096	!-- Transfer of information to the other cpus
2097	! CALL MPI_ALLREDUCE( omega_gen, omega_gen_old, nturbines, &
2098	! MPI_REAL,MPI_SUM, comm2d, ierr )
2099	#if defined( __parallel )
2100	CALL MPI_ALLREDUCE( torque_gen, torque_gen_old, nturbines, &
2101	MPI_REAL, MPI_SUM, comm2d, ierr )
2102	CALL MPI_ALLREDUCE( omega_rot_l, omega_rot, nturbines, &
2103	MPI_REAL, MPI_SUM, comm2d, ierr )
2104	CALL MPI_ALLREDUCE( omega_gen_f, omega_gen_f_old, nturbines, &
2105	MPI_REAL, MPI_SUM, comm2d, ierr )
2106	#else
2107	torque_gen_old = torque_gen
2108	omega_rot = omega_rot_l
2109	omega_gen_f_old = omega_gen_f
2110	#endif
2111
2112	ENDIF
2113
2114	DO inot = 1, nturbines
2115
2116	IF ( myid == 0 ) THEN
2117	IF ( openfile_turb_mod(400+inot)%opened ) THEN
2118	WRITE ( 400+inot, 106 ) simulated_time, omega_rot(inot), &
2119	omega_gen(inot), torque_gen_old(inot), &
2120	torque_total(inot), pitch_add(inot), &
2121	torque_gen_old(inot)omega_gen(inot)gen_eff, &
2122	torque_total(inot)omega_rot(inot)air_dens, &
2123	thrust_rotor(inot), &
2124	wdir(inot)*180.0_wp/pi, &
2125	(phi_yaw(inot))*180.0_wp/pi
2126
2127	ELSE
2128
2129	WRITE ( turbine_id,'(I2.2)') inot
2130	OPEN ( 400+inot, FILE=( 'TURBINE_PARAMETERS'//turbine_id ), &
2131	FORM='FORMATTED' )
2132	WRITE ( 400+inot, 105 ) inot
2133	WRITE ( 400+inot, 106 ) simulated_time, omega_rot(inot), &
2134	omega_gen(inot), torque_gen_old(inot), &
2135	torque_total(inot), pitch_add(inot), &
2136	torque_gen_old(inot)omega_gen(inot)gen_eff, &
2137	torque_total(inot)omega_rot(inot)air_dens, &
2138	thrust_rotor(inot), &
2139	wdir(inot)*180.0_wp/pi, &
2140	(phi_yaw(inot))*180.0_wp/pi
2141	ENDIF
2142	ENDIF
2143
2144	!-- Set open flag
2145	openfile_turb_mod(400+inot)%opened = .TRUE.
2146	ENDDO !-- end of loop over turbines
2147
2148	ENDIF
2149
2150	CALL cpu_log( log_point_s(61), 'wtm_forces', 'stop' )
2151
2152	!
2153	!-- Formats
2154	105 FORMAT ('Turbine control data for turbine ',I2,1X,':'/ &
2155	&'----------------------------------------'/ &
2156	&' Time RSpeed GSpeed ', &
2157	'GenTorque AeroTorque Pitch Power(Gen) Power(Rot) ', &
2158	'RotThrust WDirection YawOrient')
2159
2160	106 FORMAT (F9.3,2X,F7.3,2X,F7.2,2X,F9.1,3X,F9.1,1X,F6.2,2X,F10.1,2X, &
2161	F10.1,1X,F9.1,2X,F7.2,1X,F7.2)
2162
2163
2164	END SUBROUTINE wtm_forces
2165
2166
2167	!------------------------------------------------------------------------------!
2168	! Description:
2169	! ------------
2170	!> Yaw controller for the wind turbine model
2171	!------------------------------------------------------------------------------!
2172	SUBROUTINE wtm_yawcontrol( inot )
2173
2174	USE constants
2175	USE kinds
2176
2177	IMPLICIT NONE
2178
2179	INTEGER(iwp) :: inot
2180	INTEGER(iwp) :: i_wd_30
2181	REAL(wp) :: missal
2182
2183	i_wd_30 = 0_iwp
2184
2185	!
2186	!-- The yaw controller computes a 30s running mean of the wind direction.
2187	!-- If the difference between turbine alignment and wind direction exceeds
2188	!-- 5Â°, the turbine is yawed. The mechanism stops as soon as the 2s-running
2189	!-- mean of the missalignment is smaller than 0.5Â°.
2190	!-- Attention: If the timestep during the simulation changes significantly
2191	!-- the lengths of the running means change and it does not correspond to
2192	!-- 30s/2s anymore.
2193	!-- ! Needs to be modified for these situations !
2194	!-- For wind from the east, the averaging of the wind direction could cause
2195	!-- problems and the yaw controller is probably flawed. -> Routine for
2196	!-- averaging needs to be improved!
2197	!
2198	!-- Check if turbine is not yawing
2199	IF ( .NOT. doyaw(inot) ) THEN
2200	!
2201	!-- Write current wind direction into array
2202	wd30_l = wd30(inot,:)
2203	wd30_l = CSHIFT( wd30_l, SHIFT=-1 )
2204	wd30_l(1) = wdir(inot)
2205	!
2206	!-- Check if array is full ( no more dummies )
2207	IF ( .NOT. ANY( wd30_l == 999.) ) THEN
2208
2209	missal = SUM( wd30_l ) / SIZE( wd30_l ) - phi_yaw(inot)
2210	!
2211	!-- Check if turbine is missaligned by more than max_miss
2212	IF ( ABS( missal ) > max_miss ) THEN
2213	!
2214	!-- Check in which direction to yaw
2215	yawdir(inot) = SIGN( 1.0_wp, missal )
2216	!
2217	!-- Start yawing of turbine
2218	phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d
2219	doyaw(inot) = .TRUE.
2220	wd30_l = 999. ! fill with dummies again
2221	ENDIF
2222	ENDIF
2223
2224	wd30(inot,:) = wd30_l
2225
2226	!
2227	!-- If turbine is already yawing:
2228	!-- Initialize 2 s running mean and yaw until the missalignment is smaller
2229	!-- than min_miss
2230
2231	ELSE
2232	!
2233	!-- Initialize 2 s running mean
2234	wd2_l = wd2(inot,:)
2235	wd2_l = CSHIFT( wd2_l, SHIFT = -1 )
2236	wd2_l(1) = wdir(inot)
2237	!
2238	!-- Check if array is full ( no more dummies )
2239	IF ( .NOT. ANY( wd2_l == 999.0_wp ) ) THEN
2240	!
2241	!-- Calculate missalignment of turbine
2242	missal = SUM( wd2_l - phi_yaw(inot) ) / SIZE( wd2_l )
2243	!
2244	!-- Check if missalignment is still larger than 0.5 degree and if the
2245	!-- yaw direction is still right
2246	IF ( ( ABS( missal ) > min_miss ) .AND. &
2247	( yawdir(inot) == SIGN( 1.0_wp, missal ) ) ) THEN
2248	!
2249	!-- Continue yawing
2250	phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d
2251	ELSE
2252	!
2253	!-- Stop yawing
2254	doyaw(inot) = .FALSE.
2255	wd2_l = 999.0_wp ! fill with dummies again
2256	ENDIF
2257	ELSE
2258	!
2259	!-- Continue yawing
2260	phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d
2261	ENDIF
2262
2263	wd2(inot,:) = wd2_l
2264
2265	ENDIF
2266
2267	END SUBROUTINE wtm_yawcontrol
2268
2269
2270	!------------------------------------------------------------------------------!
2271	! Description:
2272	! ------------
2273	!> Initialization of the speed control
2274	!------------------------------------------------------------------------------!
2275	SUBROUTINE wtm_init_speed_control
2276
2277
2278	IMPLICIT NONE
2279
2280	!
2281	!-- If speed control is set, remaining variables and control_parameters for
2282	!-- the control algorithm are calculated
2283	!
2284	!-- Calculate slope constant for region 15
2285	slope15 = ( slope2 * min_reg2 * min_reg2 ) / ( min_reg2 - min_reg15 )
2286	!
2287	!-- Calculate upper limit of slipage region
2288	vs_sysp = rated_genspeed / 1.1_wp
2289	!
2290	!-- Calculate slope of slipage region
2291	slope25 = ( rated_power / rated_genspeed ) / &
2292	( rated_genspeed - vs_sysp )
2293	!
2294	!-- Calculate lower limit of slipage region
2295	min_reg25 = ( slope25 - SQRT( slope25 * ( slope25 - 4.0_wp * &
2296	slope2 * vs_sysp ) ) ) / &
2297	( 2.0_wp * slope2 )
2298	!
2299	!-- Frequency for the simple low pass filter
2300	Fcorner = 0.25_wp
2301	!
2302	!-- At the first timestep the torque is set to its maximum to prevent
2303	!-- an overspeeding of the rotor
2304	torque_gen_old(:) = max_torque_gen
2305
2306	END SUBROUTINE wtm_init_speed_control
2307
2308
2309	!------------------------------------------------------------------------------!
2310	! Description:
2311	! ------------
2312	!> Simple controller for the regulation of the rotor speed
2313	!------------------------------------------------------------------------------!
2314	SUBROUTINE wtm_speed_control( inot )
2315
2316
2317	IMPLICIT NONE
2318
2319	INTEGER(iwp) :: inot
2320
2321
2322
2323	!
2324	!-- The controller is based on the fortran script from Jonkman
2325	!-- et al. 2009 "Definition of a 5 MW Reference Wind Turbine for
2326	!-- offshore system developement"
2327
2328	!
2329	!-- The generator speed is filtered by a low pass filter
2330	!-- for the control of the generator torque
2331	lp_coeff = EXP( -2.0_wp * 3.14_wp * dt_3d * Fcorner )
2332	omega_gen_f(inot) = ( 1.0_wp - lp_coeff ) * omega_gen(inot) + lp_coeff *&
2333	omega_gen_f_old(inot)
2334
2335	IF ( omega_gen_f(inot) <= min_reg15 ) THEN
2336	!
2337	!-- Region 1: Generator torque is set to zero to accelerate the rotor:
2338	torque_gen(inot) = 0
2339
2340	ELSEIF ( omega_gen_f(inot) <= min_reg2 ) THEN
2341	!
2342	!-- Region 1.5: Generator torque is increasing linearly with rotor speed:
2343	torque_gen(inot) = slope15 * ( omega_gen_f(inot) - min_reg15 )
2344
2345	ELSEIF ( omega_gen_f(inot) <= min_reg25 ) THEN
2346	!
2347	!-- Region 2: Generator torque is increased by the square of the generator
2348	!-- speed to keep the TSR optimal:
2349	torque_gen(inot) = slope2 * omega_gen_f(inot) * omega_gen_f(inot)
2350
2351	ELSEIF ( omega_gen_f(inot) < rated_genspeed ) THEN
2352	!
2353	!-- Region 2.5: Slipage region between 2 and 3:
2354	torque_gen(inot) = slope25 * ( omega_gen_f(inot) - vs_sysp )
2355
2356	ELSE
2357	!
2358	!-- Region 3: Generator torque is antiproportional to the rotor speed to
2359	!-- keep the power constant:
2360	torque_gen(inot) = rated_power / omega_gen_f(inot)
2361
2362	ENDIF
2363	!
2364	!-- Calculate torque rate and confine with a max
2365	trq_rate = ( torque_gen(inot) - torque_gen_old(inot) ) / dt_3d
2366	trq_rate = MIN( MAX( trq_rate, -1.0_wp * max_trq_rate ), max_trq_rate )
2367	!
2368	!-- Calculate new gen torque and confine with max torque
2369	torque_gen(inot) = torque_gen_old(inot) + trq_rate * dt_3d
2370	torque_gen(inot) = MIN( torque_gen(inot), max_torque_gen )
2371	!
2372	!-- Overwrite values for next timestep
2373	omega_rot_l(inot) = omega_gen(inot) / gear_ratio
2374
2375
2376	END SUBROUTINE wtm_speed_control
2377
2378
2379	!------------------------------------------------------------------------------!
2380	! Description:
2381	! ------------
2382	!> Application of the additional forces generated by the wind turbine on the
2383	!> flow components (tendency terms)
2384	!> Call for all grid points
2385	!------------------------------------------------------------------------------!
2386	SUBROUTINE wtm_tendencies( component )
2387
2388
2389	IMPLICIT NONE
2390
2391	INTEGER(iwp) :: component !< prognostic variable (u,v,w)
2392	INTEGER(iwp) :: i !< running index
2393	INTEGER(iwp) :: j !< running index
2394	INTEGER(iwp) :: k !< running index
2395
2396
2397	SELECT CASE ( component )
2398
2399	CASE ( 1 )
2400	!
2401	!-- Apply the x-component of the force to the u-component of the flow:
2402	IF ( simulated_time >= time_turbine_on ) THEN
2403	DO i = nxlg, nxrg
2404	DO j = nysg, nyng
2405	DO k = nzb_u_inner(j,i)+1, k_hub(1) + k_smear(1)
2406	!
2407	!-- Calculate the thrust generated by the nacelle and the tower
2408	tend_nac_x = 0.5_wp * nac_cd_surf(k,j,i) * &
2409	SIGN( u(k,j,i)**2 , u(k,j,i) )
2410	tend_tow_x = 0.5_wp * tow_cd_surf(k,j,i) * &
2411	SIGN( u(k,j,i)**2 , u(k,j,i) )
2412
2413	tend(k,j,i) = tend(k,j,i) - rot_tend_x(k,j,i) &
2414	- tend_nac_x - tend_tow_x
2415	ENDDO
2416	ENDDO
2417	ENDDO
2418	ENDIF
2419
2420	CASE ( 2 )
2421	!
2422	!-- Apply the y-component of the force to the v-component of the flow:
2423	IF ( simulated_time >= time_turbine_on ) THEN
2424	DO i = nxlg, nxrg
2425	DO j = nysg, nyng
2426	DO k = nzb_v_inner(j,i)+1, k_hub(1) + k_smear(1)
2427	tend_nac_y = 0.5_wp * nac_cd_surf(k,j,i) * &
2428	SIGN( v(k,j,i)**2 , v(k,j,i) )
2429	tend_tow_y = 0.5_wp * tow_cd_surf(k,j,i) * &
2430	SIGN( v(k,j,i)**2 , v(k,j,i) )
2431	tend(k,j,i) = tend(k,j,i) - rot_tend_y(k,j,i) &
2432	- tend_nac_y - tend_tow_y
2433	ENDDO
2434	ENDDO
2435	ENDDO
2436	ENDIF
2437
2438	CASE ( 3 )
2439	!
2440	!-- Apply the z-component of the force to the w-component of the flow:
2441	IF ( simulated_time >= time_turbine_on ) THEN
2442	DO i = nxlg, nxrg
2443	DO j = nysg, nyng
2444	DO k = nzb_w_inner(j,i)+1, k_hub(1) + k_smear(1)
2445	tend(k,j,i) = tend(k,j,i) - rot_tend_z(k,j,i)
2446	ENDDO
2447	ENDDO
2448	ENDDO
2449	ENDIF
2450
2451
2452	CASE DEFAULT
2453
2454	WRITE( message_string, * ) 'unknown prognostic variable: ', component
2455	CALL message( 'wtm_tendencies', 'PA04??', 1, 2, 0, 6, 0 )
2456
2457	END SELECT
2458
2459
2460	END SUBROUTINE wtm_tendencies
2461
2462
2463	!------------------------------------------------------------------------------!
2464	! Description:
2465	! ------------
2466	!> Application of the additional forces generated by the wind turbine on the
2467	!> flow components (tendency terms)
2468	!> Call for grid point i,j
2469	!------------------------------------------------------------------------------!
2470	SUBROUTINE wtm_tendencies_ij( i, j, component )
2471
2472
2473	IMPLICIT NONE
2474
2475	INTEGER(iwp) :: component !< prognostic variable (u,v,w)
2476	INTEGER(iwp) :: i !< running index
2477	INTEGER(iwp) :: j !< running index
2478	INTEGER(iwp) :: k !< running index
2479
2480	SELECT CASE ( component )
2481
2482	CASE ( 1 )
2483	!
2484	!-- Apply the x-component of the force to the u-component of the flow:
2485	IF ( simulated_time >= time_turbine_on ) THEN
2486
2487	DO k = nzb_u_inner(j,i)+1, k_hub(1) + k_smear(1)
2488	!
2489	!-- Calculate the thrust generated by the nacelle and the tower
2490	tend_nac_x = 0.5_wp * nac_cd_surf(k,j,i) * &
2491	SIGN( u(k,j,i)**2 , u(k,j,i) )
2492	tend_tow_x = 0.5_wp * tow_cd_surf(k,j,i) * &
2493	SIGN( u(k,j,i)**2 , u(k,j,i) )
2494	tend(k,j,i) = tend(k,j,i) - rot_tend_x(k,j,i) &
2495	- tend_nac_x - tend_tow_x
2496	ENDDO
2497	ENDIF
2498
2499	CASE ( 2 )
2500	!
2501	!-- Apply the y-component of the force to the v-component of the flow:
2502	IF ( simulated_time >= time_turbine_on ) THEN
2503	DO k = nzb_v_inner(j,i)+1, k_hub(1) + k_smear(1)
2504	tend_nac_y = 0.5_wp * nac_cd_surf(k,j,i) * &
2505	SIGN( v(k,j,i)**2 , v(k,j,i) )
2506	tend_tow_y = 0.5_wp * tow_cd_surf(k,j,i) * &
2507	SIGN( v(k,j,i)**2 , v(k,j,i) )
2508	tend(k,j,i) = tend(k,j,i) - rot_tend_y(k,j,i) &
2509	- tend_nac_y - tend_tow_y
2510	ENDDO
2511	ENDIF
2512
2513	CASE ( 3 )
2514	!
2515	!-- Apply the z-component of the force to the w-component of the flow:
2516	IF ( simulated_time >= time_turbine_on ) THEN
2517	DO k = nzb_w_inner(j,i)+1, k_hub(1) + k_smear(1)
2518	tend(k,j,i) = tend(k,j,i) - rot_tend_z(k,j,i)
2519	ENDDO
2520	ENDIF
2521
2522
2523	CASE DEFAULT
2524
2525	WRITE( message_string, * ) 'unknown prognostic variable: ', component
2526	CALL message( 'wtm_tendencies', 'PA04??', 1, 2, 0, 6, 0 )
2527
2528	END SELECT
2529
2530
2531	END SUBROUTINE wtm_tendencies_ij
2532
2533	END MODULE wind_turbine_model_mod

Note: See TracBrowser for help on using the repository browser.

Download in other formats:

| Impressum | ©Leibniz Universität Hannover |