Home

Context Navigation

source: palm/trunk/SOURCE/wind_turbine_model_mod.f90 @ 1925

Last change on this file since 1925 was 1917, checked in by witha, 9 years ago
Corrected documented changes in the file headers
Property svn:keywords set to `Id`
File size: 105.3 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 terms
6	! of the GNU General Public License as published by the Free Software Foundation,
7	! either version 3 of the License, or (at your option) any later version.
8	!
9	! PALM is distributed in the hope that it will be useful, but WITHOUT ANY
10	! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
11	! A PARTICULAR PURPOSE. See the GNU General Public License for more details.
12	!
13	! You should have received a copy of the GNU General Public License along with
14	! PALM. If not, see <http://www.gnu.org/licenses/>.
15	!
16	! Copyright 1997-2016 Leibniz Universitaet Hannover
17	!------------------------------------------------------------------------------!
18	!
19	! Current revisions:
20	! -----------------
21	!
22	!
23	! Former revisions:
24	! -----------------
25	! $Id: wind_turbine_model_mod.f90 1917 2016-05-27 14:28:12Z hellstea $
26	!
27	! 1914 2016-05-26 14:44:07Z witha
28	! Initial revision
29	!
30	!
31	! Description:
32	! ------------
33	!> This module calculates the effect of wind turbines on the flow fields. The
34	!> initial version contains only the advanced actuator disk with rotation method
35	!> (ADM-R).
36	!> The wind turbines include the tower effect, can be yawed and tilted.
37	!> The wind turbine model includes controllers for rotational speed, pitch and
38	!> yaw.
39	!> Currently some specifications of the NREL 5 MW reference turbine
40	!> are hardcoded whereas most input data comes from separate files (currently
41	!> external, planned to be included as namelist which will be read in
42	!> automatically).
43	!>
44	!> @todo Revise code according to PALM Coding Standard
45	!> @todo Implement ADM and ALM turbine models
46	!> @todo Generate header information
47	!> @todo Implement further parameter checks and error messages
48	!> @todo Revise and add code documentation
49	!> @todo Output turbine parameters as timeseries
50	!> @todo Include additional output variables
51	!> @todo Revise smearing the forces for turbines in yaw
52	!> @todo Revise nacelle and tower parameterization
53	!> @todo Allow different turbine types in one simulation
54	!
55	!------------------------------------------------------------------------------!
56	MODULE wind_turbine_model_mod
57
58	USE arrays_3d, &
59	ONLY: dd2zu, tend, u, v, w, zu, zw
60
61	USE constants
62
63	USE control_parameters, &
64	ONLY: dt_3d, dz, message_string, simulated_time
65
66	USE cpulog, &
67	ONLY: cpu_log, log_point_s
68
69	USE grid_variables, &
70	ONLY: ddx, dx, ddy, dy
71
72	USE indices, &
73	ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nz, &
74	nzb, nzb_u_inner, nzb_v_inner, nzb_w_inner, nzt
75
76	USE kinds
77
78	USE pegrid
79
80
81	IMPLICIT NONE
82
83	PRIVATE
84
85	LOGICAL :: wind_turbine=.FALSE. !< switch for use of wind turbine model
86
87	!
88	!-- Variables specified in the namelist wind_turbine_par
89
90	INTEGER(iwp) :: nairfoils = 8 !< number of airfoils of the used turbine model (for ADM-R and ALM)
91	INTEGER(iwp) :: nturbines = 1 !< number of turbines
92
93	LOGICAL :: pitch_control = .FALSE. !< switch for use of pitch controller
94	LOGICAL :: speed_control = .FALSE. !< switch for use of speed controller
95	LOGICAL :: yaw_control = .FALSE. !< switch for use of yaw controller
96
97	REAL(wp) :: segment_length = 1.0_wp !< length of the segments, the rotor area is divided into
98	!< (in tangential direction, as factor of MIN(dx,dy,dz))
99	REAL(wp) :: segment_width = 0.5_wp !< width of the segments, the rotor area is divided into
100	!< (in radial direction, as factor of MIN(dx,dy,dz))
101	REAL(wp) :: time_turbine_on = 0.0_wp !< time at which turbines are started
102	REAL(wp) :: tilt = 0.0_wp !< vertical tilt of the rotor [degree] ( positive = backwards )
103
104	REAL(wp), DIMENSION(1:100) :: dtow = 0.0_wp !< tower diameter [m]
105	REAL(wp), DIMENSION(1:100) :: omega_rot = 0.0_wp !< inital or constant rotor speed [rad/s]
106	REAL(wp), DIMENSION(1:100) :: phi_yaw = 0.0_wp !< yaw angle [degree] ( clockwise, 0 = facing west )
107	REAL(wp), DIMENSION(1:100) :: pitch_add = 0.0_wp !< constant pitch angle
108	REAL(wp), DIMENSION(1:100) :: rcx = 9999999.9_wp !< position of hub in x-direction
109	REAL(wp), DIMENSION(1:100) :: rcy = 9999999.9_wp !< position of hub in y-direction
110	REAL(wp), DIMENSION(1:100) :: rcz = 9999999.9_wp !< position of hub in z-direction
111	REAL(wp), DIMENSION(1:100) :: rnac = 0.0_wp !< nacelle diameter [m]
112	REAL(wp), DIMENSION(1:100) :: rr = 63.0_wp !< rotor radius [m]
113	REAL(wp), DIMENSION(1:100) :: turb_cd_nacelle = 0.85_wp !< drag coefficient for nacelle
114	REAL(wp), DIMENSION(1:100) :: turb_cd_tower = 1.2_wp !< drag coefficient for tower
115
116	!
117	!-- Variables specified in the namelist for speed controller
118	!-- Default values are from the NREL 5MW research turbine (Jonkman, 2008)
119
120	REAL(wp) :: rated_power = 5296610.0_wp !< rated turbine power [W]
121	REAL(wp) :: gear_ratio = 97.0_wp !< Gear ratio from rotor to generator
122	REAL(wp) :: inertia_rot = 34784179.0_wp !< Inertia of the rotor [kg/m2]
123	REAL(wp) :: inertia_gen = 534.116_wp !< Inertia of the generator [kg/m2]
124	REAL(wp) :: gen_eff = 0.944_wp !< Electric efficiency of the generator
125	REAL(wp) :: gear_eff = 1.0_wp !< Loss between rotor and generator
126	REAL(wp) :: air_dens = 1.225_wp !< Air density to convert to W [kg/m3]
127	REAL(wp) :: rated_genspeed = 121.6805_wp !< Rated generator speed [rad/s]
128	REAL(wp) :: max_torque_gen = 47402.91_wp !< Maximum of the generator torque [Nm]
129	REAL(wp) :: slope2 = 2.332287_wp !< Slope constant for region 2
130	REAL(wp) :: min_reg2 = 91.21091_wp !< Lower generator speed boundary of region 2 [rad/s]
131	REAL(wp) :: min_reg15 = 70.16224_wp !< Lower generator speed boundary of region 1.5 [rad/s]
132	REAL(wp) :: max_trq_rate = 15000.0_wp !< Max generator torque increase [Nm/s]
133	REAL(wp) :: pitch_rate = 8.0_wp !< Max pitch rate [degree/s]
134
135
136	!
137	!-- Variables specified in the namelist for yaw control
138
139	REAL(wp) :: yaw_speed = 0.005236_wp !< speed of the yaw actuator [rad/s]
140	REAL(wp) :: max_miss = 0.08726_wp !< maximum tolerated yaw missalignment [rad]
141	REAL(wp) :: min_miss = 0.008726_wp !< minimum yaw missalignment for which the actuator stops [rad]
142
143	!
144	!-- Set flag for output files TURBINE_PARAMETERS
145	TYPE file_status
146	LOGICAL :: opened, opened_before
147	END TYPE file_status
148
149	TYPE(file_status), DIMENSION(500) :: openfile_turb_mod = &
150	file_status(.FALSE.,.FALSE.)
151
152	!
153	!-- Variables for initialization of the turbine model
154
155	INTEGER(iwp) :: inot !< turbine loop index (turbine id)
156	INTEGER(iwp) :: nsegs_max !< maximum number of segments (all turbines, required for allocation of arrays)
157	INTEGER(iwp) :: nrings_max !< maximum number of rings (all turbines, required for allocation of arrays)
158	INTEGER(iwp) :: ring !< ring loop index (ring number)
159	INTEGER(iwp) :: rr_int !<
160	INTEGER(iwp) :: upper_end !<
161
162	INTEGER(iwp), DIMENSION(1) :: lct !<
163
164	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: i_hub !< index belonging to x-position of the turbine
165	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: i_smear !< index defining the area for the smearing of the forces (x-direction)
166	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: j_hub !< index belonging to y-position of the turbine
167	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: j_smear !< index defining the area for the smearing of the forces (y-direction)
168	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: k_hub !< index belonging to hub height
169	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: k_smear !< index defining the area for the smearing of the forces (z-direction)
170	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nrings !< number of rings per turbine
171	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nsegs_total !< total number of segments per turbine
172
173	INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: nsegs !< number of segments per ring and turbine
174
175	!
176	!- parameters for the smearing from the rotor to the cartesian grid
177	REAL(wp) :: pol_a !< parameter for the polynomial smearing fct
178	REAL(wp) :: pol_b !< parameter for the polynomial smearing fct
179	REAL(wp) :: delta_t_factor !<
180	REAL(wp) :: eps_factor !<
181	REAL(wp) :: eps_min !<
182	REAL(wp) :: eps_min2 !<
183	REAL(wp) :: sqrt_arg !<
184
185	!
186	!-- Variables for the calculation of lift and drag coefficients
187	REAL(wp), DIMENSION(:), ALLOCATABLE :: ard !<
188	REAL(wp), DIMENSION(:), ALLOCATABLE :: crd !<
189	REAL(wp), DIMENSION(:), ALLOCATABLE :: delta_r !< radial segment length
190	REAL(wp), DIMENSION(:), ALLOCATABLE :: lrd !<
191
192	REAL(wp) :: accu_cl_cd_tab = 0.1_wp !< Accuracy of the interpolation of
193	!< the lift and drag coeff [deg]
194
195	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cd_tab !< table of the blade drag coefficient
196	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cl_tab !< table of the blade lift coefficient
197
198	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: nac_cd_surf !< 3d field of the tower drag coefficient
199	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: tow_cd_surf !< 3d field of the nacelle drag coefficient
200
201	!
202	!-- Variables for the calculation of the forces
203
204	REAL(wp) :: cur_r !<
205	REAL(wp) :: delta_t !< tangential segment length
206	REAL(wp) :: phi_rotor !<
207	REAL(wp) :: pre_factor !<
208	REAL(wp) :: torque_seg !<
209	REAL(wp) :: u_int_l !<
210	REAL(wp) :: u_int_u !<
211	REAL(wp) :: u_rot !<
212	REAL(wp) :: v_int_l !<
213	REAL(wp) :: v_int_u !<
214	REAL(wp) :: w_int_l !<
215	REAL(wp) :: w_int_u !<
216	!
217	!- Tendencies from the nacelle and tower thrust
218	REAL(wp) :: tend_nac_x = 0.0_wp !<
219	REAL(wp) :: tend_tow_x = 0.0_wp !<
220	REAL(wp) :: tend_nac_y = 0.0_wp !<
221	REAL(wp) :: tend_tow_y = 0.0_wp !<
222
223	REAL(wp), DIMENSION(:), ALLOCATABLE :: alpha_attack !<
224	REAL(wp), DIMENSION(:), ALLOCATABLE :: chord !<
225	REAL(wp), DIMENSION(:), ALLOCATABLE :: omega_gen !< curr. generator speed
226	REAL(wp), DIMENSION(:), ALLOCATABLE :: phi_rel !<
227	REAL(wp), DIMENSION(:), ALLOCATABLE :: pitch_add_old!<
228	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_total !<
229	REAL(wp), DIMENSION(:), ALLOCATABLE :: thrust_rotor !<
230	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl !<
231	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd !<
232	REAL(wp), DIMENSION(:), ALLOCATABLE :: vrel !<
233	REAL(wp), DIMENSION(:), ALLOCATABLE :: vtheta !<
234
235	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: rbx, rby, rbz !< coordinates of the blade elements
236	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: rotx, roty, rotz !< normal vectors to the rotor coordinates
237
238	!
239	!- Fields for the interpolation of velocities on the rotor grid
240	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: u_int !<
241	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: u_int_1_l !<
242	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: v_int !<
243	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: v_int_1_l !<
244	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: w_int !<
245	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: w_int_1_l !<
246
247	!
248	!- rotor tendencies on the segments
249	REAL(wp), DIMENSION(:), ALLOCATABLE :: thrust_seg !<
250	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_seg_y !<
251	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_seg_z !<
252
253	!
254	!- rotor tendencies on the rings
255	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: thrust_ring !<
256	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: torque_ring_y !<
257	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: torque_ring_z !<
258
259	!
260	!- rotor tendencies on rotor grids for all turbines
261	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: thrust !<
262	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: torque_y !<
263	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: torque_z !<
264
265	!
266	!- rotor tendencies on coordinate grid
267	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_x !<
268	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_y !<
269	REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_z !<
270	!
271	!- variables for the rotation of the rotor coordinates
272	REAL(wp), DIMENSION(1:100,1:3,1:3) :: rot_coord_trans !< matrix for rotation of rotor coordinates
273
274	REAL(wp), DIMENSION(1:3) :: rot_eigen_rad !<
275	REAL(wp), DIMENSION(1:3) :: rot_eigen_azi !<
276	REAL(wp), DIMENSION(1:3) :: rot_eigen_nor !<
277	REAL(wp), DIMENSION(1:3) :: re !<
278	REAL(wp), DIMENSION(1:3) :: rea !<
279	REAL(wp), DIMENSION(1:3) :: ren !<
280	REAL(wp), DIMENSION(1:3) :: rote !<
281	REAL(wp), DIMENSION(1:3) :: rota !<
282	REAL(wp), DIMENSION(1:3) :: rotn !<
283
284	!
285	!-- Fixed variables for the speed controller
286
287	LOGICAL :: start_up = .TRUE. !<
288
289	REAL(wp) :: Fcorner !< corner freq for the controller low pass filter
290	REAL(wp) :: min_reg25 !< min region 2.5
291	REAL(wp) :: om_rate !< rotor speed change
292	REAL(wp) :: slope15 !< slope in region 1.5
293	REAL(wp) :: slope25 !< slope in region 2.5
294	REAL(wp) :: trq_rate !< torque change
295	REAL(wp) :: vs_sysp !<
296	REAL(wp) :: lp_coeff !< coeff for the controller low pass filter
297
298	REAL(wp), DIMENSION(:), ALLOCATABLE :: omega_gen_old !< last gen. speed
299	REAL(wp), DIMENSION(:), ALLOCATABLE :: omega_gen_f !< filtered gen. sp
300	REAL(wp), DIMENSION(:), ALLOCATABLE :: omega_gen_f_old !< last filt. gen. sp
301	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_gen !< generator torque
302	REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_gen_old !< last gen. torque
303
304	REAL(wp), DIMENSION(100) :: omega_rot_l = 0.0_wp !< local rot speed [rad/s]
305	!
306	!-- Fixed variables for the yaw controller
307
308	REAL(wp), DIMENSION(:) , ALLOCATABLE :: yawdir !< direction to yaw
309	REAL(wp), DIMENSION(:) , ALLOCATABLE :: phi_yaw_l !< local (cpu) yaw angle
310	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wd30_l !< local (cpu) long running avg of the wd
311	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wd2_l !< local (cpu) short running avg of the wd
312	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wdir !< wind direction at hub
313	REAL(wp), DIMENSION(:) , ALLOCATABLE :: u_inflow !< wind speed at hub
314	REAL(wp), DIMENSION(:) , ALLOCATABLE :: wdir_l !<
315	REAL(wp), DIMENSION(:) , ALLOCATABLE :: u_inflow_l !<
316	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: wd30 !<
317	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: wd2 !<
318	LOGICAL, DIMENSION(1:100) :: doyaw = .FALSE. !<
319	INTEGER(iwp) :: WDLON !<
320	INTEGER(iwp) :: WDSHO !<
321
322
323	SAVE
324
325
326	INTERFACE wtm_parin
327	MODULE PROCEDURE wtm_parin
328	END INTERFACE wtm_parin
329
330	INTERFACE wtm_check_parameters
331	MODULE PROCEDURE wtm_check_parameters
332	END INTERFACE wtm_check_parameters
333
334	INTERFACE wtm_init_arrays
335	MODULE PROCEDURE wtm_init_arrays
336	END INTERFACE wtm_init_arrays
337
338	INTERFACE wtm_init
339	MODULE PROCEDURE wtm_init
340	END INTERFACE wtm_init
341
342	INTERFACE wtm_read_blade_tables
343	MODULE PROCEDURE wtm_read_blade_tables
344	END INTERFACE wtm_read_blade_tables
345
346	INTERFACE wtm_forces
347	MODULE PROCEDURE wtm_forces
348	MODULE PROCEDURE wtm_yawcontrol
349	END INTERFACE wtm_forces
350
351	INTERFACE wtm_rotate_rotor
352	MODULE PROCEDURE wtm_rotate_rotor
353	END INTERFACE wtm_rotate_rotor
354
355	INTERFACE wtm_speed_control
356	MODULE PROCEDURE wtm_init_speed_control
357	MODULE PROCEDURE wtm_speed_control
358	END INTERFACE wtm_speed_control
359
360	INTERFACE wtm_tendencies
361	MODULE PROCEDURE wtm_tendencies
362	MODULE PROCEDURE wtm_tendencies_ij
363	END INTERFACE wtm_tendencies
364
365
366	PUBLIC wtm_check_parameters, wtm_forces, wtm_init, wtm_init_arrays, &
367	wtm_parin, wtm_tendencies, wtm_tendencies_ij, wind_turbine
368
369	CONTAINS
370
371
372	!------------------------------------------------------------------------------!
373	! Description:
374	! ------------
375	!> Parin for &wind_turbine_par for wind turbine model
376	!------------------------------------------------------------------------------!
377	SUBROUTINE wtm_parin
378
379
380	IMPLICIT NONE
381
382	INTEGER(iwp) :: ierrn !<
383
384	CHARACTER (LEN=80) :: line !< dummy string that contains the current line of the parameter file
385
386	NAMELIST /wind_turbine_par/ air_dens, dtow, gear_eff, gear_ratio, &
387	gen_eff, inertia_gen, inertia_rot, max_miss, &
388	max_torque_gen, max_trq_rate, min_miss, &
389	min_reg15, min_reg2, nairfoils, nturbines, &
390	omega_rot, phi_yaw, pitch_add, pitch_control,&
391	rated_genspeed, rated_power, rcx, rcy, rcz, &
392	rnac, rr, segment_length, segment_width, &
393	slope2, speed_control, tilt, time_turbine_on,&
394	turb_cd_nacelle, turb_cd_tower, &
395	yaw_control, yaw_speed
396
397	!
398	!-- Try to find wind turbine model package
399	REWIND ( 11 )
400	line = ' '
401	DO WHILE ( INDEX( line, '&wind_turbine_par' ) == 0 )
402	READ ( 11, '(A)', END=10 ) line
403	ENDDO
404	BACKSPACE ( 11 )
405
406	!
407	!-- Read user-defined namelist
408	READ ( 11, wind_turbine_par, IOSTAT=ierrn )
409
410	IF ( ierrn < 0 ) THEN
411	message_string = 'errors in \$wind_turbine_par'
412	CALL message( 'wtm_parin', 'PA0???', 1, 2, 0, 6, 0 )
413	ENDIF
414
415	!
416	!-- Set flag that indicates that the wind turbine model is switched on
417	wind_turbine = .TRUE.
418
419	10 CONTINUE ! TBD Change from continue, mit ierrn machen
420
421
422	END SUBROUTINE wtm_parin
423
424	SUBROUTINE wtm_check_parameters
425
426
427	IMPLICIT NONE
428
429	IF ( ( .NOT.speed_control ) .AND. pitch_control ) THEN
430	message_string = 'pitch_control = .TRUE. requires '// &
431	'speed_control = .TRUE.'
432	CALL message( 'wtm_check_parameters', 'PA0???', 1, 2, 0, 6, 0 )
433	ENDIF
434
435	IF ( ANY( omega_rot(1:nturbines) <= 0.0 ) ) THEN
436	message_string = 'omega_rot <= 0.0, Please set omega_rot to ' // &
437	'a value larger than zero'
438	CALL message( 'wtm_check_parameters', 'PA0???', 1, 2, 0, 6, 0 )
439	ENDIF
440
441
442	IF ( ANY( rcx(1:nturbines) == 9999999.9_wp ) .OR. &
443	ANY( rcy(1:nturbines) == 9999999.9_wp ) .OR. &
444	ANY( rcz(1:nturbines) == 9999999.9_wp ) ) THEN
445
446	message_string = 'rcx, rcy, rcz ' // &
447	'have to be given for each turbine.'
448	CALL message( 'wtm_check_parameters', 'PA0???', 1, 2, 0, 6, 0 )
449
450	ENDIF
451
452
453	END SUBROUTINE wtm_check_parameters
454
455
456	!------------------------------------------------------------------------------!
457	! Description:
458	! ------------
459	!> Allocate wind turbine model arrays
460	!------------------------------------------------------------------------------!
461	SUBROUTINE wtm_init_arrays
462
463
464	IMPLICIT NONE
465
466	REAL(wp) :: delta_r_factor !<
467	REAL(wp) :: delta_r_init !<
468
469	!
470	!-- To be able to allocate arrays with dimension of rotor rings and segments,
471	!-- the maximum possible numbers of rings and segments have to be calculated:
472
473	ALLOCATE( nrings(1:nturbines) )
474	ALLOCATE( delta_r(1:nturbines) )
475
476	nrings(:) = 0
477	delta_r(:) = 0.0_wp
478
479	!
480	!-- Thickness (radial) of each ring and length (tangential) of each segment:
481	delta_r_factor = segment_width
482	delta_t_factor = segment_length
483	delta_r_init = delta_r_factor * MIN( dx, dy, dz)
484	delta_t = delta_t_factor * MIN( dx, dy, dz)
485
486	DO inot = 1, nturbines
487	!
488	!-- Determine number of rings:
489	nrings(inot) = NINT( rr(inot) / delta_r_init )
490
491	delta_r(inot) = rr(inot) / nrings(inot)
492
493	ENDDO
494
495	nrings_max = MAXVAL(nrings)
496
497	ALLOCATE( nsegs(1:nrings_max,1:nturbines) )
498	ALLOCATE( nsegs_total(1:nturbines) )
499
500	nsegs(:,:) = 0
501	nsegs_total(:) = 0
502
503
504	DO inot = 1, nturbines
505	DO ring = 1, nrings(inot)
506	!
507	!-- Determine number of segments for each ring:
508	nsegs(ring,inot) = MAX( 8, CEILING( delta_r_factor * pi * &
509	( 2.0_wp * ring - 1.0_wp ) / &
510	delta_t_factor ) )
511	ENDDO
512	!
513	!-- Total sum of all rotor segments:
514	nsegs_total(inot) = SUM( nsegs(:,inot) )
515
516	ENDDO
517
518	!
519	!-- Maximum number of segments per ring:
520	nsegs_max = MAXVAL(nsegs)
521
522	!!
523	!!-- TODO: Folgendes im Header ausgeben!
524	! IF ( myid == 0 ) THEN
525	! PRINT*, 'nrings(1) = ', nrings(1)
526	! PRINT*, '--------------------------------------------------'
527	! PRINT*, 'nsegs(:,1) = ', nsegs(:,1)
528	! PRINT*, '--------------------------------------------------'
529	! PRINT*, 'nrings_max = ', nrings_max
530	! PRINT*, 'nsegs_max = ', nsegs_max
531	! PRINT*, 'nsegs_total(1) = ', nsegs_total(1)
532	! ENDIF
533
534
535	!
536	!-- Allocate 1D arrays (dimension = number of turbines)
537	ALLOCATE( i_hub(1:nturbines) )
538	ALLOCATE( i_smear(1:nturbines) )
539	ALLOCATE( j_hub(1:nturbines) )
540	ALLOCATE( j_smear(1:nturbines) )
541	ALLOCATE( k_hub(1:nturbines) )
542	ALLOCATE( k_smear(1:nturbines) )
543	ALLOCATE( torque_total(1:nturbines) )
544	ALLOCATE( thrust_rotor(1:nturbines) )
545
546	!
547	!-- Allocation of the 1D arrays for speed pitch_control
548	ALLOCATE( omega_gen(1:nturbines) )
549	ALLOCATE( omega_gen_old(1:nturbines) )
550	ALLOCATE( omega_gen_f(1:nturbines) )
551	ALLOCATE( omega_gen_f_old(1:nturbines) )
552	ALLOCATE( pitch_add_old(1:nturbines) )
553	ALLOCATE( torque_gen(1:nturbines) )
554	ALLOCATE( torque_gen_old(1:nturbines) )
555
556	!
557	!-- Allocation of the 1D arrays for yaw control
558	ALLOCATE( yawdir(1:nturbines) )
559	ALLOCATE( u_inflow(1:nturbines) )
560	ALLOCATE( wdir(1:nturbines) )
561	ALLOCATE( u_inflow_l(1:nturbines) )
562	ALLOCATE( wdir_l(1:nturbines) )
563	ALLOCATE( phi_yaw_l(1:nturbines) )
564
565	!
566	!-- Allocate 1D arrays (dimension = number of rotor segments)
567	ALLOCATE( alpha_attack(1:nsegs_max) )
568	ALLOCATE( chord(1:nsegs_max) )
569	ALLOCATE( phi_rel(1:nsegs_max) )
570	ALLOCATE( thrust_seg(1:nsegs_max) )
571	ALLOCATE( torque_seg_y(1:nsegs_max) )
572	ALLOCATE( torque_seg_z(1:nsegs_max) )
573	ALLOCATE( turb_cd(1:nsegs_max) )
574	ALLOCATE( turb_cl(1:nsegs_max) )
575	ALLOCATE( vrel(1:nsegs_max) )
576	ALLOCATE( vtheta(1:nsegs_max) )
577
578	!
579	!-- Allocate 2D arrays (dimension = number of rotor rings and segments)
580	ALLOCATE( rbx(1:nrings_max,1:nsegs_max) )
581	ALLOCATE( rby(1:nrings_max,1:nsegs_max) )
582	ALLOCATE( rbz(1:nrings_max,1:nsegs_max) )
583	ALLOCATE( thrust_ring(1:nrings_max,1:nsegs_max) )
584	ALLOCATE( torque_ring_y(1:nrings_max,1:nsegs_max) )
585	ALLOCATE( torque_ring_z(1:nrings_max,1:nsegs_max) )
586
587	!
588	!-- Allocate additional 2D arrays
589	ALLOCATE( rotx(1:nturbines,1:3) )
590	ALLOCATE( roty(1:nturbines,1:3) )
591	ALLOCATE( rotz(1:nturbines,1:3) )
592
593	!
594	!-- Allocate 3D arrays (dimension = number of grid points)
595	ALLOCATE( nac_cd_surf(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
596	ALLOCATE( rot_tend_x(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
597	ALLOCATE( rot_tend_y(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
598	ALLOCATE( rot_tend_z(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
599	ALLOCATE( thrust(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
600	ALLOCATE( torque_y(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
601	ALLOCATE( torque_z(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
602	ALLOCATE( tow_cd_surf(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
603
604	!
605	!-- Allocate additional 3D arrays
606	ALLOCATE( u_int(1:nturbines,1:nrings_max,1:nsegs_max) )
607	ALLOCATE( u_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) )
608	ALLOCATE( v_int(1:nturbines,1:nrings_max,1:nsegs_max) )
609	ALLOCATE( v_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) )
610	ALLOCATE( w_int(1:nturbines,1:nrings_max,1:nsegs_max) )
611	ALLOCATE( w_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) )
612
613	!
614	!-- All of the arrays are initialized with a value of zero:
615	i_hub(:) = 0
616	i_smear(:) = 0
617	j_hub(:) = 0
618	j_smear(:) = 0
619	k_hub(:) = 0
620	k_smear(:) = 0
621
622	torque_total(:) = 0.0_wp
623	thrust_rotor(:) = 0.0_wp
624
625	omega_gen(:) = 0.0_wp
626	omega_gen_old(:) = 0.0_wp
627	omega_gen_f(:) = 0.0_wp
628	omega_gen_f_old(:) = 0.0_wp
629	pitch_add_old(:) = 0.0_wp
630	torque_gen(:) = 0.0_wp
631	torque_gen_old(:) = 0.0_wp
632
633	yawdir(:) = 0.0_wp
634	wdir(:) = 0.0_wp
635	u_inflow(:) = 0.0_wp
636
637	!
638	!-- Allocate 1D arrays (dimension = number of rotor segments)
639	alpha_attack(:) = 0.0_wp
640	chord(:) = 0.0_wp
641	phi_rel(:) = 0.0_wp
642	thrust_seg(:) = 0.0_wp
643	torque_seg_y(:) = 0.0_wp
644	torque_seg_z(:) = 0.0_wp
645	turb_cd(:) = 0.0_wp
646	turb_cl(:) = 0.0_wp
647	vrel(:) = 0.0_wp
648	vtheta(:) = 0.0_wp
649
650	rbx(:,:) = 0.0_wp
651	rby(:,:) = 0.0_wp
652	rbz(:,:) = 0.0_wp
653	thrust_ring(:,:) = 0.0_wp
654	torque_ring_y(:,:) = 0.0_wp
655	torque_ring_z(:,:) = 0.0_wp
656
657	rotx(:,:) = 0.0_wp
658	roty(:,:) = 0.0_wp
659	rotz(:,:) = 0.0_wp
660	turb_cl_tab(:,:) = 0.0_wp
661	turb_cd_tab(:,:) = 0.0_wp
662
663	nac_cd_surf(:,:,:) = 0.0_wp
664	rot_tend_x(:,:,:) = 0.0_wp
665	rot_tend_y(:,:,:) = 0.0_wp
666	rot_tend_z(:,:,:) = 0.0_wp
667	thrust(:,:,:) = 0.0_wp
668	torque_y(:,:,:) = 0.0_wp
669	torque_z(:,:,:) = 0.0_wp
670	tow_cd_surf(:,:,:) = 0.0_wp
671
672	u_int(:,:,:) = 0.0_wp
673	u_int_1_l(:,:,:) = 0.0_wp
674	v_int(:,:,:) = 0.0_wp
675	v_int_1_l(:,:,:) = 0.0_wp
676	w_int(:,:,:) = 0.0_wp
677	w_int_1_l(:,:,:) = 0.0_wp
678
679
680	END SUBROUTINE wtm_init_arrays
681
682
683	!------------------------------------------------------------------------------!
684	! Description:
685	! ------------
686	!> Initialization of the wind turbine model
687	!------------------------------------------------------------------------------!
688	SUBROUTINE wtm_init
689
690
691	IMPLICIT NONE
692
693	INTEGER(iwp) :: i !< running index
694	INTEGER(iwp) :: j !< running index
695	INTEGER(iwp) :: k !< running index
696
697	!
698	!-- Help variables for the smearing function
699	REAL(wp) :: eps_kernel !<
700
701	!
702	!-- Help variables for calculation of the tower drag
703	INTEGER(iwp) :: tower_n !<
704	INTEGER(iwp) :: tower_s !<
705	!
706	!-- Help variables for the calulaction of the nacelle drag
707	INTEGER(iwp) :: i_ip !<
708	INTEGER(iwp) :: i_ipg !<
709
710	REAL(wp) :: yvalue
711	REAL(wp) :: dy_int !<
712	REAL(wp) :: dz_int !<
713
714	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: circle_points !<
715
716	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nacb !<
717	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nacl !<
718	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nacr !<
719	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nact !<
720
721	ALLOCATE( index_nacb(1:nturbines) )
722	ALLOCATE( index_nacl(1:nturbines) )
723	ALLOCATE( index_nacr(1:nturbines) )
724	ALLOCATE( index_nact(1:nturbines) )
725
726
727	IF ( speed_control) THEN
728
729	CALL wtm_speed_control
730
731	ENDIF
732
733	!
734	!------------------------------------------------------------------------------!
735	!-- Calculation of parameters for the regularization kernel
736	!-- (smearing of the forces)
737	!------------------------------------------------------------------------------!
738	!
739	!-- In the following, some of the required parameters for the smearing will
740	!-- be calculated:
741
742	!-- The kernel is set equal to twice the grid spacing which has turned out to
743	!-- be a reasonable value (see e.g. Troldborg et al. (2013), Wind Energy,
744	!-- DOI: 10.1002/we.1608):
745	eps_kernel = 2.0_wp * dx
746	!
747	!-- The zero point (eps_min) of the polynomial function must be the following
748	!-- if the integral of the polynomial function (for values < eps_min) shall
749	!-- be equal to the integral of the Gaussian function used before:
750	eps_min = ( 105.0_wp / 32.0_wp )*( 1.0_wp / 3.0_wp ) &
751	pi*( 1.0_wp / 6.0_wp ) eps_kernel
752	!
753	!-- Square of eps_min:
754	eps_min2 = eps_min**2
755	!
756	!-- Parameters in the polynomial function:
757	pol_a = 1.0_wp / eps_min**4
758	pol_b = 2.0_wp / eps_min**2
759	!
760	!-- Normalization factor which is the inverse of the integral of the smearing
761	!-- function:
762	eps_factor = 105.0_wp / ( 32.0_wp * pi * eps_min**3 )
763
764	!-- Change tilt angle to rad:
765	tilt = tilt * pi / 180.0_wp
766
767	!
768	!-- Change yaw angle to rad:
769	phi_yaw(:) = phi_yaw(:) * pi / 180.0_wp
770
771
772	DO inot = 1, nturbines
773	!
774	!-- Rotate the rotor coordinates in case yaw and tilt are defined
775	CALL wtm_rotate_rotor( inot )
776
777	!
778	!-- Determine the indices of the hub height
779	i_hub(inot) = INT( rcx(inot) / dx )
780	j_hub(inot) = INT( ( rcy(inot) + 0.5_wp * dy ) / dy )
781	k_hub(inot) = INT( ( rcz(inot) + 0.5_wp * dz ) / dz )
782
783	!
784	!-- Determining the area to which the smearing of the forces is applied.
785	!-- As smearing now is effectively applied only for distances smaller than
786	!-- eps_min, the smearing area can be further limited and regarded as a
787	!-- function of eps_min:
788	i_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dx )
789	j_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dy )
790	k_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dz )
791
792	ENDDO
793
794	!
795	!------------------------------------------------------------------------------!
796	!-- Determine the area within each grid cell that overlaps with the area
797	!-- of the nacelle and the tower (needed for calculation of the forces)
798	!------------------------------------------------------------------------------!
799	!
800	!-- Note: so far this is only a 2D version, in that the mean flow is
801	!-- perpendicular to the rotor area.
802
803	!
804	!-- Allocation of the array containing information on the intersection points
805	!-- between rotor disk and the numerical grid:
806	upper_end = ( ny + 1 ) * 10000
807
808	ALLOCATE( circle_points(1:2,1:upper_end) )
809
810	circle_points(:,:) = 0.0_wp
811
812
813	DO inot = 1, nturbines ! loop over number of turbines
814	!
815	!-- Determine the grid index (u-grid) that corresponds to the location of
816	!-- the rotor center (reduces the amount of calculations in the case that
817	!-- the mean flow is perpendicular to the rotor area):
818	i = i_hub(inot)
819
820	!
821	!-- Determine the left and the right edge of the nacelle (corresponding
822	!-- grid point indices):
823	index_nacl(inot) = INT( ( rcy(inot) - rnac(inot) + 0.5_wp * dy ) / dy )
824	index_nacr(inot) = INT( ( rcy(inot) + rnac(inot) + 0.5_wp * dy ) / dy )
825	!
826	!-- Determine the bottom and the top edge of the nacelle (corresponding
827	!-- grid point indices).The grid point index has to be increased by 1, as
828	!-- the first level for the u-component (index 0) is situated below the
829	!-- surface. All points between z=0 and z=dz/s would already be contained
830	!-- in grid box 1.
831	index_nacb(inot) = INT( ( rcz(inot) - rnac(inot) ) / dz ) + 1
832	index_nact(inot) = INT( ( rcz(inot) + rnac(inot) ) / dz ) + 1
833
834	!
835	!-- Determine the indices of the grid boxes containing the left and
836	!-- the right boundaries of the tower:
837	tower_n = ( rcy(inot) + 0.5_wp * dtow(inot) - 0.5_wp * dy ) / dy
838	tower_s = ( rcy(inot) - 0.5_wp * dtow(inot) - 0.5_wp * dy ) / dy
839
840	!
841	!-- Determine the fraction of the grid box area overlapping with the tower
842	!-- area and multiply it with the drag of the tower:
843	IF ( ( nxlg <= i ) .AND. ( nxrg >= i ) ) THEN
844
845	DO j = nys, nyn
846	!
847	!-- Loop from south to north boundary of tower
848	IF ( ( j >= tower_s ) .AND. ( j <= tower_n ) ) THEN
849
850	DO k = nzb, nzt
851
852	IF ( k == k_hub(inot) ) THEN
853	IF ( tower_n - tower_s >= 1 ) THEN
854	!
855	!-- leftmost and rightmost grid box:
856	IF ( j == tower_s ) THEN
857	tow_cd_surf(k,j,i) = ( rcz(inot) - &
858	( k_hub(inot) * dz - 0.5_wp * dz ) ) * & ! extension in z-direction
859	( ( tower_s + 1.0_wp + 0.5_wp ) * dy - &
860	( rcy(inot) - 0.5_wp * dtow(inot) ) ) * & ! extension in y-direction
861	turb_cd_tower(inot)
862	ELSEIF ( j == tower_n ) THEN
863	tow_cd_surf(k,j,i) = ( rcz(inot) - &
864	( k_hub(inot) * dz - 0.5_wp * dz ) ) * & ! extension in z-direction
865	( ( rcy(inot) + 0.5_wp * dtow(inot) ) - &
866	( tower_n + 0.5_wp ) * dy ) * & ! extension in y-direction
867	turb_cd_tower(inot)
868	!
869	!-- grid boxes inbetween
870	!-- (where tow_cd_surf = grid box area):
871	ELSE
872	tow_cd_surf(k,j,i) = ( rcz(inot) - &
873	( k_hub(inot) * dz - 0.5_wp * dz ) ) * &
874	dy * turb_cd_tower(inot)
875	ENDIF
876	!
877	!-- tower lies completely within one grid box:
878	ELSE
879	tow_cd_surf(k,j,i) = ( rcz(inot) - &
880	( k_hub(inot) * dz - 0.5_wp * dz ) ) * &
881	dtow(inot) * turb_cd_tower(inot)
882	ENDIF
883	!
884	!-- In case that k is smaller than k_hub the following actions
885	!-- are carried out:
886	ELSEIF ( k < k_hub(inot) ) THEN
887
888	IF ( ( tower_n - tower_s ) >= 1 ) THEN
889	!
890	!-- leftmost and rightmost grid box:
891	IF ( j == tower_s ) THEN
892	tow_cd_surf(k,j,i) = dz * ( &
893	( tower_s + 1 + 0.5_wp ) * dy - &
894	( rcy(inot) - 0.5_wp * dtow(inot) ) &
895	) * turb_cd_tower(inot)
896	ELSEIF ( j == tower_n ) THEN
897	tow_cd_surf(k,j,i) = dz * ( &
898	( rcy(inot) + 0.5_wp * dtow(inot) ) - &
899	( tower_n + 0.5_wp ) * dy &
900	) * turb_cd_tower(inot)
901	!
902	!-- grid boxes inbetween
903	!-- (where tow_cd_surf = grid box area):
904	ELSE
905	tow_cd_surf(k,j,i) = dz * dy * turb_cd_tower(inot)
906	ENDIF
907	!
908	!-- tower lies completely within one grid box:
909	ELSE
910	tow_cd_surf(k,j,i) = dz * dtow(inot) * &
911	turb_cd_tower(inot)
912	ENDIF ! end if larger than grid box
913
914	ENDIF ! end if k == k_hub
915
916	ENDDO ! end loop over k
917
918	ENDIF ! end if inside north and south boundary of tower
919
920	ENDDO ! end loop over j
921
922	ENDIF ! end if hub inside domain + ghostpoints
923
924
925	CALL exchange_horiz( tow_cd_surf, nbgp )
926
927	!
928	!-- Calculation of the nacelle area
929	!-- CAUTION: Currently disabled due to segmentation faults on the FLOW HPC
930	!-- cluster (Oldenburg)
931	!!
932	!!-- Tabulate the points on the circle that are required in the following for
933	!!-- the calculation of the Riemann integral (node points; they are called
934	!!-- circle_points in the following):
935	!
936	! dy_int = dy / 10000.0_wp
937	!
938	! DO i_ip = 1, upper_end
939	! yvalue = dy_int * ( i_ip - 0.5_wp ) + 0.5_wp * dy !<--- segmentation fault
940	! sqrt_arg = rnac(inot)2 - ( yvalue - rcy(inot) )2 !<--- segmentation fault
941	! IF ( sqrt_arg >= 0.0_wp ) THEN
942	!!
943	!!-- bottom intersection point
944	! circle_points(1,i_ip) = rcz(inot) - SQRT( sqrt_arg )
945	!!
946	!!-- top intersection point
947	! circle_points(2,i_ip) = rcz(inot) + SQRT( sqrt_arg ) !<--- segmentation fault
948	! ELSE
949	! circle_points(:,i_ip) = -111111 !<--- segmentation fault
950	! ENDIF
951	! ENDDO
952	!
953	!
954	! DO j = nys, nyn
955	!!
956	!!-- In case that the grid box is located completely outside the nacelle
957	!!-- (y) it can automatically be stated that there is no overlap between
958	!!-- the grid box and the nacelle and consequently we can set
959	!!-- nac_cd_surf(:,j,i) = 0.0:
960	! IF ( ( j >= index_nacl(inot) ) .AND. ( j <= index_nacr(inot) ) ) THEN
961	! DO k = nzb+1, nzt
962	!!
963	!!-- In case that the grid box is located completely outside the
964	!!-- nacelle (z) it can automatically be stated that there is no
965	!!-- overlap between the grid box and the nacelle and consequently
966	!!-- we can set nac_cd_surf(k,j,i) = 0.0:
967	! IF ( ( k >= index_nacb(inot) ) .OR. &
968	! ( k <= index_nact(inot) ) ) THEN
969	!!
970	!!-- For all other cases Riemann integrals are calculated.
971	!!-- Here, the points on the circle that have been determined
972	!!-- above are used in order to calculate the overlap between the
973	!!-- gridbox and the nacelle area (area approached by 10000
974	!!-- rectangulars dz_int * dy_int):
975	! DO i_ipg = 1, 10000
976	! dz_int = dz
977	! i_ip = j * 10000 + i_ipg
978	!!
979	!!-- Determine the vertical extension dz_int of the circle
980	!!-- within the current grid box:
981	! IF ( ( circle_points(2,i_ip) < zw(k) ) .AND. & !<--- segmentation fault
982	! ( circle_points(2,i_ip) >= zw(k-1) ) ) THEN
983	! dz_int = dz_int - & !<--- segmentation fault
984	! ( zw(k) - circle_points(2,i_ip) )
985	! ENDIF
986	! IF ( ( circle_points(1,i_ip) <= zw(k) ) .AND. & !<--- segmentation fault
987	! ( circle_points(1,i_ip) > zw(k-1) ) ) THEN
988	! dz_int = dz_int - &
989	! ( circle_points(1,i_ip) - zw(k-1) )
990	! ENDIF
991	! IF ( zw(k-1) > circle_points(2,i_ip) ) THEN
992	! dz_int = 0.0_wp
993	! ENDIF
994	! IF ( zw(k) < circle_points(1,i_ip) ) THEN
995	! dz_int = 0.0_wp
996	! ENDIF
997	! IF ( ( nxlg <= i ) .AND. ( nxrg >= i ) ) THEN
998	! nac_cd_surf(k,j,i) = nac_cd_surf(k,j,i) + & !<--- segmentation fault
999	! dy_int * dz_int * turb_cd_nacelle(inot)
1000	! ENDIF
1001	! ENDDO
1002	! ENDIF
1003	! ENDDO
1004	! ENDIF
1005	!
1006	! ENDDO
1007	!
1008	! CALL exchange_horiz( nac_cd_surf, nbgp ) !<--- segmentation fault
1009
1010	ENDDO ! end of loop over turbines
1011
1012	tow_cd_surf = tow_cd_surf / ( dx * dy * dz ) ! Normalize tower drag
1013	nac_cd_surf = nac_cd_surf / ( dx * dy * dz ) ! Normalize nacelle drag
1014
1015	CALL wtm_read_blade_tables
1016
1017	END SUBROUTINE wtm_init
1018
1019
1020	!------------------------------------------------------------------------------!
1021	! Description:
1022	! ------------
1023	!> Read in layout of the rotor blade , the lift and drag tables
1024	!> and the distribution of lift and drag tables along the blade
1025	!------------------------------------------------------------------------------!
1026	!
1027	SUBROUTINE wtm_read_blade_tables
1028
1029
1030	IMPLICIT NONE
1031
1032	INTEGER(iwp) :: ii !< running index
1033	INTEGER(iwp) :: jj !< running index
1034
1035	INTEGER(iwp) :: ierrn !<
1036
1037	CHARACTER(200) :: chmess !< Read in string
1038
1039	INTEGER(iwp) :: dlen !< no. rows of local table
1040	INTEGER(iwp) :: dlenbl !< no. rows of cd, cl table
1041	INTEGER(iwp) :: ialpha !< table position of current alpha value
1042	INTEGER(iwp) :: iialpha !<
1043	INTEGER(iwp) :: iir !<
1044	INTEGER(iwp) :: radres !< radial resolution
1045	INTEGER(iwp) :: t1 !< no. of airfoil
1046	INTEGER(iwp) :: t2 !< no. of airfoil
1047	INTEGER(iwp) :: trow !<
1048	INTEGER(iwp) :: dlenbl_int !< no. rows of interpolated cd, cl tables
1049
1050	REAL(wp) :: alpha_attack_i !<
1051	REAL(wp) :: weight_a !<
1052	REAL(wp) :: weight_b !<
1053
1054	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: ttoint1 !<
1055	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: ttoint2 !<
1056
1057	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd_sel1 !<
1058	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd_sel2 !<
1059	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl_sel1 !<
1060	REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl_sel2 !<
1061	REAL(wp), DIMENSION(:), ALLOCATABLE :: read_cl_cd !< read in var array
1062
1063	REAL(wp), DIMENSION(:), ALLOCATABLE :: alpha_attack_tab !<
1064	REAL(wp), DIMENSION(:), ALLOCATABLE :: trad1 !<
1065	REAL(wp), DIMENSION(:), ALLOCATABLE :: trad2 !<
1066	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cd_table !<
1067	REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cl_table !<
1068
1069	ALLOCATE ( read_cl_cd(1:2*nairfoils+1) )
1070
1071	!
1072	!-- Read in the distribution of lift and drag tables along the blade, the
1073	!-- layout of the rotor blade and the lift and drag tables:
1074
1075	OPEN ( 201, FILE='WTM_DATA', STATUS='OLD', FORM='FORMATTED', IOSTAT=ierrn )
1076
1077	IF ( ierrn /= 0 ) THEN
1078	message_string = 'file WTM_DATA does not exist'
1079	CALL message( 'wtm_init', 'PA0???', 1, 2, 0, 6, 0 )
1080	ENDIF
1081	!
1082	!-- Read distribution table:
1083
1084	dlen = 0
1085
1086	READ ( 201, '(3/)' )
1087
1088	rloop3: DO
1089	READ ( 201, *, IOSTAT=ierrn ) chmess
1090	IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop3
1091	dlen = dlen + 1
1092	ENDDO rloop3
1093
1094	ALLOCATE( trad1(1:dlen), trad2(1:dlen), ttoint1(1:dlen), ttoint2(1:dlen))
1095
1096	DO jj = 1,dlen+1
1097	BACKSPACE ( 201, IOSTAT=ierrn )
1098	ENDDO
1099
1100	DO jj = 1,dlen
1101	READ ( 201, * ) trad1(jj), trad2(jj), ttoint1(jj), ttoint2(jj)
1102	ENDDO
1103
1104	!
1105	!-- Read layout table:
1106
1107	dlen = 0
1108
1109	READ ( 201, '(3/)')
1110
1111	rloop1: DO
1112	READ ( 201, *, IOSTAT=ierrn ) chmess
1113	IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop1
1114	dlen = dlen + 1
1115	ENDDO rloop1
1116
1117	ALLOCATE( lrd(1:dlen), ard(1:dlen), crd(1:dlen) )
1118	DO jj = 1, dlen+1
1119	BACKSPACE ( 201, IOSTAT=ierrn )
1120	ENDDO
1121	DO jj = 1, dlen
1122	READ ( 201, * ) lrd(jj), ard(jj), crd(jj)
1123	ENDDO
1124
1125	!
1126	!-- Read tables (turb_cl(alpha),turb_cd(alpha) for the different profiles:
1127
1128	dlen = 0
1129
1130	READ ( 201, '(3/)' )
1131
1132	rloop2: DO
1133	READ ( 201, *, IOSTAT=ierrn ) chmess
1134	IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop2
1135	dlen = dlen + 1
1136	ENDDO rloop2
1137
1138	ALLOCATE( alpha_attack_tab(1:dlen), turb_cl_table(1:dlen,1:nairfoils), &
1139	turb_cd_table(1:dlen,1:nairfoils) )
1140
1141	DO jj = 1,dlen+1
1142	BACKSPACE ( 201, IOSTAT=ierrn )
1143	ENDDO
1144
1145	DO jj = 1,dlen
1146	READ ( 201, * ) read_cl_cd
1147	alpha_attack_tab(jj) = read_cl_cd(1)
1148	DO ii= 1, nairfoils
1149	turb_cl_table(jj,ii) = read_cl_cd(ii*2)
1150	turb_cd_table(jj,ii) = read_cl_cd(ii*2+1)
1151	ENDDO
1152
1153	ENDDO
1154
1155	dlenbl = dlen
1156
1157	CLOSE ( 201 )
1158
1159	!
1160	!-- For each possible radial position (resolution: 0.1 m --> 630 values) and
1161	!-- each possible angle of attack (resolution: 0.01 degrees --> 36000 values!)
1162	!-- determine the lift and drag coefficient by interpolating between the
1163	!-- tabulated values of each table (interpolate to current angle of attack)
1164	!-- and between the tables (interpolate to current radial position):
1165
1166	ALLOCATE( turb_cl_sel1(0:dlenbl) )
1167	ALLOCATE( turb_cl_sel2(0:dlenbl) )
1168	ALLOCATE( turb_cd_sel1(0:dlenbl) )
1169	ALLOCATE( turb_cd_sel2(0:dlenbl) )
1170
1171	radres = INT( rr(1) * 10.0_wp ) + 1_iwp
1172	dlenbl_int = INT( 360.0_wp / accu_cl_cd_tab ) + 1_iwp
1173
1174
1175	ALLOCATE( turb_cl_tab(0:dlenbl_int,1:radres) )
1176	ALLOCATE( turb_cd_tab(0:dlenbl_int,1:radres) )
1177
1178
1179	DO iir = 1, radres ! loop over radius
1180
1181	DO iialpha = 1, dlenbl_int ! loop over angles
1182
1183	cur_r = ( iir - 1_iwp ) * 0.1_wp
1184	alpha_attack_i = -180.0_wp + REAL( iialpha-1 ) * accu_cl_cd_tab
1185	ialpha = 1
1186
1187	DO WHILE ( alpha_attack_i > alpha_attack_tab(ialpha) )
1188	ialpha = ialpha + 1
1189	ENDDO
1190	!
1191	!-- Find position in table
1192	lct = MINLOC( ABS( trad1 - cur_r ) )
1193	! lct(1) = lct(1)
1194
1195	IF ( ( trad1(lct(1)) - cur_r ) .GT. 0.0 ) THEN
1196	lct(1) = lct(1) - 1
1197	ENDIF
1198
1199	trow = lct(1)
1200	!
1201	!-- Calculate weights for interpolation
1202	weight_a = ( trad2(trow) - cur_r ) / ( trad2(trow) - trad1(trow) )
1203	weight_b = ( cur_r - trad1(trow) ) / ( trad2(trow) - trad1(trow) )
1204	t1 = ttoint1(trow)
1205	t2 = ttoint2(trow)
1206
1207	IF ( t1 .EQ. t2 ) THEN ! if both are the same, the weights are NaN
1208	weight_a = 0.5_wp ! then do interpolate in between same twice
1209	weight_b = 0.5_wp ! using 0.5 as weight
1210	ENDIF
1211
1212	IF ( t1 == 0 .AND. t2 == 0 ) THEN
1213	turb_cd_sel1 = 0.0_wp
1214	turb_cd_sel2 = 0.0_wp
1215	turb_cl_sel1 = 0.0_wp
1216	turb_cl_sel2 = 0.0_wp
1217	ELSE
1218	turb_cd_sel1 = turb_cd_table(:,t1)
1219	turb_cd_sel2 = turb_cd_table(:,t2)
1220	turb_cl_sel1 = turb_cl_table(:,t1)
1221	turb_cl_sel2 = turb_cl_table(:,t2)
1222	ENDIF
1223
1224	!
1225	!-- Interpolation of lift and drag coefficiencts on fine grid of radius
1226	!-- segments and angles of attack
1227
1228	turb_cl_tab(iialpha,iir) = ( alpha_attack_tab(ialpha) - &
1229	alpha_attack_i ) / &
1230	( alpha_attack_tab(ialpha) - &
1231	alpha_attack_tab(ialpha-1) ) * &
1232	( weight_a * turb_cl_sel1(ialpha-1) + &
1233	weight_b * turb_cl_sel2(ialpha-1) ) +&
1234	( alpha_attack_i - &
1235	alpha_attack_tab(ialpha-1) ) / &
1236	( alpha_attack_tab(ialpha) - &
1237	alpha_attack_tab(ialpha-1) ) * &
1238	( weight_a * turb_cl_sel1(ialpha) + &
1239	weight_b * turb_cl_sel2(ialpha) )
1240	turb_cd_tab(iialpha,iir) = ( alpha_attack_tab(ialpha) - &
1241	alpha_attack_i ) / &
1242	( alpha_attack_tab(ialpha) - &
1243	alpha_attack_tab(ialpha-1) ) * &
1244	( weight_a * turb_cd_sel1(ialpha-1) + &
1245	weight_b * turb_cd_sel2(ialpha-1) ) +&
1246	( alpha_attack_i - &
1247	alpha_attack_tab(ialpha-1) ) / &
1248	( alpha_attack_tab(ialpha) - &
1249	alpha_attack_tab(ialpha-1) ) * &
1250	( weight_a * turb_cd_sel1(ialpha) + &
1251	weight_b * turb_cd_sel2(ialpha) )
1252
1253	ENDDO ! end loop over angles of attack
1254
1255	ENDDO ! end loop over radius
1256
1257	END SUBROUTINE wtm_read_blade_tables
1258
1259
1260	!------------------------------------------------------------------------------!
1261	! Description:
1262	! ------------
1263	!> The projection matrix for the coordinate system of therotor disc in respect
1264	!> to the yaw and tilt angle of the rotor is calculated
1265	!------------------------------------------------------------------------------!
1266	SUBROUTINE wtm_rotate_rotor( inot )
1267
1268
1269	IMPLICIT NONE
1270
1271	INTEGER(iwp) :: inot
1272	!
1273	!-- Calculation of the rotation matrix for the application of the tilt to
1274	!-- the rotors
1275	rot_eigen_rad(1) = SIN( phi_yaw(inot) ) ! x-component of the radial eigenvector
1276	rot_eigen_rad(2) = COS( phi_yaw(inot) ) ! y-component of the radial eigenvector
1277	rot_eigen_rad(3) = 0.0_wp ! z-component of the radial eigenvector
1278
1279	rot_eigen_azi(1) = 0.0_wp ! x-component of the azimuth eigenvector
1280	rot_eigen_azi(2) = 0.0_wp ! y-component of the azimuth eigenvector
1281	rot_eigen_azi(3) = 1.0_wp ! z-component of the azimuth eigenvector
1282
1283	rot_eigen_nor(1) = COS( phi_yaw(inot) ) ! x-component of the normal eigenvector
1284	rot_eigen_nor(2) = -SIN( phi_yaw(inot) ) ! y-component of the normal eigenvector
1285	rot_eigen_nor(3) = 0.0_wp ! z-component of the normal eigenvector
1286
1287	!
1288	!-- Calculation of the coordinate transformation matrix to apply a tilt to
1289	!-- the rotor. If tilt = 0, rot_coord_trans is a unit matrix.
1290
1291	rot_coord_trans(inot,1,1) = rot_eigen_rad(1)*2 &
1292	( 1.0_wp - COS( tilt ) ) + COS( tilt )
1293	rot_coord_trans(inot,1,2) = rot_eigen_rad(1) * rot_eigen_rad(2) * &
1294	( 1.0_wp - COS( tilt ) ) - &
1295	rot_eigen_rad(3) * SIN( tilt )
1296	rot_coord_trans(inot,1,3) = rot_eigen_rad(1) * rot_eigen_rad(3) * &
1297	( 1.0_wp - COS( tilt ) ) + &
1298	rot_eigen_rad(2) * SIN( tilt )
1299	rot_coord_trans(inot,2,1) = rot_eigen_rad(2) * rot_eigen_rad(1) * &
1300	( 1.0_wp - COS( tilt ) ) + &
1301	rot_eigen_rad(3) * SIN( tilt )
1302	rot_coord_trans(inot,2,2) = rot_eigen_rad(2)*2 &
1303	( 1.0_wp - COS( tilt ) ) + COS( tilt )
1304	rot_coord_trans(inot,2,3) = rot_eigen_rad(2) * rot_eigen_rad(3) * &
1305	( 1.0_wp - COS( tilt ) ) - &
1306	rot_eigen_rad(1) * SIN( tilt )
1307	rot_coord_trans(inot,3,1) = rot_eigen_rad(3) * rot_eigen_rad(1) * &
1308	( 1.0_wp - COS( tilt ) ) - &
1309	rot_eigen_rad(2) * SIN( tilt )
1310	rot_coord_trans(inot,3,2) = rot_eigen_rad(3) * rot_eigen_rad(2) * &
1311	( 1.0_wp - COS( tilt ) ) + &
1312	rot_eigen_rad(1) * SIN( tilt )
1313	rot_coord_trans(inot,3,3) = rot_eigen_rad(3)*2 &
1314	( 1.0_wp - COS( tilt ) ) + COS( tilt )
1315
1316	!
1317	!-- Vectors for the Transformation of forces from the rotor's spheric
1318	!-- coordinate system to the cartesian coordinate system
1319	rotx(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_nor )
1320	roty(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_rad )
1321	rotz(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_azi )
1322
1323	END SUBROUTINE wtm_rotate_rotor
1324
1325
1326	!------------------------------------------------------------------------------!
1327	! Description:
1328	! ------------
1329	!> Calculation of the forces generated by the wind turbine
1330	!------------------------------------------------------------------------------!
1331	SUBROUTINE wtm_forces
1332
1333
1334	IMPLICIT NONE
1335
1336	CHARACTER (LEN=2) :: turbine_id
1337
1338	INTEGER(iwp) :: i, j, k !< loop indices
1339	INTEGER(iwp) :: inot !< turbine loop index (turbine id)
1340	INTEGER(iwp) :: iialpha, iir !<
1341	INTEGER(iwp) :: rseg, rseg_int !<
1342	INTEGER(iwp) :: ring, ring_int !<
1343	INTEGER(iwp) :: ii, jj, kk !<
1344
1345	REAL(wp) :: sin_rot, cos_rot !<
1346	REAL(wp) :: sin_yaw, cos_yaw !<
1347
1348	REAL(wp) :: aa, bb, cc, dd !< interpolation distances
1349	REAL(wp) :: gg !< interpolation volume var
1350
1351	REAL(wp) :: dist_u_3d, dist_v_3d, dist_w_3d !< smearing distances
1352
1353
1354	!
1355	! Variables for pitch control
1356	REAL(wp) :: torque_max=0.0_wp
1357	LOGICAL :: pitch_sw=.FALSE.
1358
1359	INTEGER(iwp), DIMENSION(1) :: lct=0
1360	REAL(wp), DIMENSION(1) :: rad_d=0.0_wp
1361
1362
1363	CALL cpu_log( log_point_s(61), 'wtm_forces', 'start' )
1364
1365
1366	IF ( simulated_time >= time_turbine_on ) THEN
1367
1368	!
1369	!-- Set forces to zero for each new time step:
1370	thrust(:,:,:) = 0.0_wp
1371	torque_y(:,:,:) = 0.0_wp
1372	torque_z(:,:,:) = 0.0_wp
1373	torque_total(:) = 0.0_wp
1374	rot_tend_x(:,:,:) = 0.0_wp
1375	rot_tend_y(:,:,:) = 0.0_wp
1376	rot_tend_z(:,:,:) = 0.0_wp
1377	thrust_rotor(:) = 0.0_wp
1378	!
1379	!-- Loop over number of turbines:
1380	DO inot = 1, nturbines
1381
1382	cos_yaw = COS(phi_yaw(inot))
1383	sin_yaw = SIN(phi_yaw(inot))
1384	!
1385	!-- Loop over rings of each turbine:
1386	DO ring = 1, nrings(inot)
1387
1388	thrust_seg(:) = 0.0_wp
1389	torque_seg_y(:) = 0.0_wp
1390	torque_seg_z(:) = 0.0_wp
1391	!
1392	!-- Determine distance between each ring (center) and the hub:
1393	cur_r = (ring - 0.5_wp) * delta_r(inot)
1394
1395	!
1396	!-- Loop over segments of each ring of each turbine:
1397	DO rseg = 1, nsegs(ring,inot)
1398	!
1399	!-- !-----------------------------------------------------------!
1400	!-- !-- Determine coordinates of the ring segments --!
1401	!-- !-----------------------------------------------------------!
1402	!
1403	!-- Determine angle of ring segment towards zero degree angle of
1404	!-- rotor system (at zero degree rotor direction vectors aligned
1405	!-- with y-axis):
1406	phi_rotor = rseg * 2.0_wp * pi / nsegs(ring,inot)
1407	cos_rot = COS( phi_rotor )
1408	sin_rot = SIN( phi_rotor )
1409
1410	!-- Now the direction vectors can be determined with respect to
1411	!-- the yaw and tilt angle:
1412	re(1) = cos_rot * sin_yaw
1413	re(2) = cos_rot * cos_yaw
1414	re(3) = sin_rot
1415
1416	rote = MATMUL( rot_coord_trans(inot,:,:), re )
1417	!
1418	!-- Coordinates of the single segments (center points):
1419	rbx(ring,rseg) = rcx(inot) + cur_r * rote(1)
1420	rby(ring,rseg) = rcy(inot) + cur_r * rote(2)
1421	rbz(ring,rseg) = rcz(inot) + cur_r * rote(3)
1422
1423	!-- !-----------------------------------------------------------!
1424	!-- !-- Interpolation of the velocity components from the --!
1425	!-- !-- cartesian grid point to the coordinates of each ring --!
1426	!-- !-- segment (follows a method used in the particle model) --!
1427	!-- !-----------------------------------------------------------!
1428
1429	u_int(inot,ring,rseg) = 0.0_wp
1430	u_int_1_l(inot,ring,rseg) = 0.0_wp
1431
1432	v_int(inot,ring,rseg) = 0.0_wp
1433	v_int_1_l(inot,ring,rseg) = 0.0_wp
1434
1435	w_int(inot,ring,rseg) = 0.0_wp
1436	w_int_1_l(inot,ring,rseg) = 0.0_wp
1437
1438	!
1439	!-- Interpolation of the u-component:
1440
1441	ii = rbx(ring,rseg) * ddx
1442	jj = ( rby(ring,rseg) - 0.5_wp * dy ) * ddy
1443	kk = ( rbz(ring,rseg) - 0.5_wp * dz ) / dz
1444	!
1445	!-- Interpolate only if all required information is available on
1446	!-- the current PE:
1447	IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN
1448	IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN
1449
1450	aa = ( ( ii + 1 ) * dx - rbx(ring,rseg) ) * &
1451	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1452	bb = ( rbx(ring,rseg) - ii * dx ) * &
1453	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1454	cc = ( ( ii+1 ) * dx - rbx(ring,rseg) ) * &
1455	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1456	dd = ( rbx(ring,rseg) - ii * dx ) * &
1457	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1458	gg = dx * dy
1459
1460	u_int_l = ( aa * u(kk,jj,ii) + &
1461	bb * u(kk,jj,ii+1) + &
1462	cc * u(kk,jj+1,ii) + &
1463	dd * u(kk,jj+1,ii+1) &
1464	) / gg
1465
1466	u_int_u = ( aa * u(kk+1,jj,ii) + &
1467	bb * u(kk+1,jj,ii+1) + &
1468	cc * u(kk+1,jj+1,ii) + &
1469	dd * u(kk+1,jj+1,ii+1) &
1470	) / gg
1471
1472	u_int_1_l(inot,ring,rseg) = u_int_l + &
1473	( rbz(ring,rseg) - zu(kk) ) / dz * &
1474	( u_int_u - u_int_l )
1475
1476	ELSE
1477	u_int_1_l(inot,ring,rseg) = 0.0_wp
1478	ENDIF
1479	ELSE
1480	u_int_1_l(inot,ring,rseg) = 0.0_wp
1481	ENDIF
1482
1483
1484	!
1485	!-- Interpolation of the v-component:
1486	ii = ( rbx(ring,rseg) - 0.5_wp * dx ) * ddx
1487	jj = rby(ring,rseg) * ddy
1488	kk = ( rbz(ring,rseg) + 0.5_wp * dz ) / dz
1489	!
1490	!-- Interpolate only if all required information is available on
1491	!-- the current PE:
1492	IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN
1493	IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN
1494
1495	aa = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1496	( ( jj + 1 ) * dy - rby(ring,rseg) )
1497	bb = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1498	( ( jj + 1 ) * dy - rby(ring,rseg) )
1499	cc = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1500	( rby(ring,rseg) - jj * dy )
1501	dd = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1502	( rby(ring,rseg) - jj * dy )
1503	gg = dx * dy
1504
1505	v_int_l = ( aa * v(kk,jj,ii) + &
1506	bb * v(kk,jj,ii+1) + &
1507	cc * v(kk,jj+1,ii) + &
1508	dd * v(kk,jj+1,ii+1) &
1509	) / gg
1510
1511	v_int_u = ( aa * v(kk+1,jj,ii) + &
1512	bb * v(kk+1,jj,ii+1) + &
1513	cc * v(kk+1,jj+1,ii) + &
1514	dd * v(kk+1,jj+1,ii+1) &
1515	) / gg
1516
1517	v_int_1_l(inot,ring,rseg) = v_int_l + &
1518	( rbz(ring,rseg) - zu(kk) ) / dz * &
1519	( v_int_u - v_int_l )
1520
1521	ELSE
1522	v_int_1_l(inot,ring,rseg) = 0.0_wp
1523	ENDIF
1524	ELSE
1525	v_int_1_l(inot,ring,rseg) = 0.0_wp
1526	ENDIF
1527
1528
1529	!
1530	!-- Interpolation of the w-component:
1531	ii = ( rbx(ring,rseg) - 0.5_wp * dx ) * ddx
1532	jj = ( rby(ring,rseg) - 0.5_wp * dy ) * ddy
1533	kk = rbz(ring,rseg) / dz
1534	!
1535	!-- Interpolate only if all required information is available on
1536	!-- the current PE:
1537	IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN
1538	IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN
1539
1540	aa = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1541	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1542	bb = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1543	( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) )
1544	cc = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * &
1545	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1546	dd = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * &
1547	( rby(ring,rseg) - ( jj + 0.5_wp ) * dy )
1548	gg = dx * dy
1549
1550	w_int_l = ( aa * w(kk,jj,ii) + &
1551	bb * w(kk,jj,ii+1) + &
1552	cc * w(kk,jj+1,ii) + &
1553	dd * w(kk,jj+1,ii+1) &
1554	) / gg
1555
1556	w_int_u = ( aa * w(kk+1,jj,ii) + &
1557	bb * w(kk+1,jj,ii+1) + &
1558	cc * w(kk+1,jj+1,ii) + &
1559	dd * w(kk+1,jj+1,ii+1) &
1560	) / gg
1561
1562	w_int_1_l(inot,ring,rseg) = w_int_l + &
1563	( rbz(ring,rseg) - zw(kk) ) / dz * &
1564	( w_int_u - w_int_l )
1565	ELSE
1566	w_int_1_l(inot,ring,rseg) = 0.0_wp
1567	ENDIF
1568	ELSE
1569	w_int_1_l(inot,ring,rseg) = 0.0_wp
1570	ENDIF
1571
1572	ENDDO
1573	ENDDO
1574
1575	ENDDO
1576
1577	!
1578	!-- Exchange between PEs (information required on each PE):
1579	#if defined( __parallel )
1580	CALL MPI_ALLREDUCE( u_int_1_l, u_int, nturbines * MAXVAL(nrings) * &
1581	MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr )
1582	CALL MPI_ALLREDUCE( v_int_1_l, v_int, nturbines * MAXVAL(nrings) * &
1583	MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr )
1584	CALL MPI_ALLREDUCE( w_int_1_l, w_int, nturbines * MAXVAL(nrings) * &
1585	MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr )
1586	#else
1587	u_int = u_int_1_l
1588	v_int = v_int_1_l
1589	w_int = w_int_1_l
1590	#endif
1591
1592
1593	!
1594	!-- Loop over number of turbines:
1595
1596	DO inot = 1, nturbines
1597	pit_loop: DO
1598
1599	IF ( pitch_sw ) THEN
1600	torque_total(inot) = 0.0_wp
1601	thrust_rotor(inot) = 0.0_wp
1602	pitch_add(inot) = pitch_add(inot) + 0.25_wp
1603	! IF ( myid == 0 ) PRINT*, 'Pitch', inot, pitch_add(inot)
1604	ELSE
1605	cos_yaw = COS(phi_yaw(inot))
1606	sin_yaw = SIN(phi_yaw(inot))
1607	IF ( pitch_control ) THEN
1608	pitch_add(inot) = MAX(pitch_add_old(inot) - pitch_rate * &
1609	dt_3d , 0.0_wp )
1610	ENDIF
1611	ENDIF
1612
1613	!
1614	!-- Loop over rings of each turbine:
1615	DO ring = 1, nrings(inot)
1616	!
1617	!-- Determine distance between each ring (center) and the hub:
1618	cur_r = (ring - 0.5_wp) * delta_r(inot)
1619	!
1620	!-- Loop over segments of each ring of each turbine:
1621	DO rseg = 1, nsegs(ring,inot)
1622	!
1623	!-- Determine angle of ring segment towards zero degree angle of
1624	!-- rotor system (at zero degree rotor direction vectors aligned
1625	!-- with y-axis):
1626	phi_rotor = rseg * 2.0_wp * pi / nsegs(ring,inot)
1627	cos_rot = COS(phi_rotor)
1628	sin_rot = SIN(phi_rotor)
1629	!
1630	!-- Now the direction vectors can be determined with respect to
1631	!-- the yaw and tilt angle:
1632	re(1) = cos_rot * sin_yaw
1633	re(2) = cos_rot * cos_yaw
1634	re(3) = sin_rot
1635
1636	! The current unit vector in azimuthal direction:
1637	rea(1) = - sin_rot * sin_yaw
1638	rea(2) = - sin_rot * cos_yaw
1639	rea(3) = cos_rot
1640
1641	!
1642	!-- To respect the yawing angle for the calculations of
1643	!-- velocities and forces the unit vectors perpendicular to the
1644	!-- rotor area in direction of the positive yaw angle are defined:
1645	ren(1) = cos_yaw
1646	ren(2) = - sin_yaw
1647	ren(3) = 0.0_wp
1648	!
1649	!-- Multiplication with the coordinate transformation matrix
1650	!-- gives the final unit vector with consideration of the rotor
1651	!-- tilt:
1652	rote = MATMUL( rot_coord_trans(inot,:,:), re )
1653	rota = MATMUL( rot_coord_trans(inot,:,:), rea )
1654	rotn = MATMUL( rot_coord_trans(inot,:,:), ren )
1655	!
1656	!-- Coordinates of the single segments (center points):
1657	rbx(ring,rseg) = rcx(inot) + cur_r * rote(1)
1658
1659	rby(ring,rseg) = rcy(inot) + cur_r * rote(2)
1660
1661	rbz(ring,rseg) = rcz(inot) + cur_r * rote(3)
1662
1663	!
1664	!-- !-----------------------------------------------------------!
1665	!-- !-- Calculation of various angles and relative velocities --!
1666	!-- !-----------------------------------------------------------!
1667	!
1668	!-- In the following the 3D-velocity field is projected its
1669	!-- components perpedicular and parallel to the rotor area
1670	!-- The calculation of forces will be done in the rotor-
1671	!-- coordinates y' and z.
1672	!-- The yaw angle will be reintroduced when the force is applied
1673	!-- on the hydrodynamic equations
1674	!
1675	!-- Projection of the xy-velocities relative to the rotor area
1676	!
1677	!-- Velocity perpendicular to the rotor area:
1678	u_rot = u_int(inot,ring,rseg)*rotn(1) + &
1679	v_int(inot,ring,rseg)*rotn(2) + &
1680	w_int(inot,ring,rseg)*rotn(3)
1681	!
1682	!-- Projection of the 3D-velocity vector in the azimuthal
1683	!-- direction:
1684	vtheta(rseg) = rota(1) * u_int(inot,ring,rseg) + &
1685	rota(2) * v_int(inot,ring,rseg) + &
1686	rota(3) * w_int(inot,ring,rseg)
1687	!
1688	!-- Determination of the angle phi_rel between the rotor plane
1689	!-- and the direction of the flow relative to the rotor:
1690
1691	phi_rel(rseg) = ATAN( u_rot / &
1692	( omega_rot(inot) * cur_r - &
1693	vtheta(rseg) ) )
1694
1695	!
1696	!-- Interpolation of the local pitch angle from tabulated values
1697	!-- to the current radial position:
1698
1699	lct=minloc(ABS(cur_r-lrd))
1700	rad_d=cur_r-lrd(lct)
1701
1702	IF (cur_r == 0.0_wp) THEN
1703	alpha_attack(rseg) = 0.0_wp
1704	ELSE IF (cur_r >= lrd(size(ard))) THEN
1705	alpha_attack(rseg) = ( ard(size(ard)) + &
1706	ard(size(ard)-1) ) / 2.0_wp
1707	ELSE
1708	alpha_attack(rseg) = ( ard(lct(1)) * &
1709	( ( lrd(lct(1)+1) - cur_r ) / &
1710	( lrd(lct(1)+1) - lrd(lct(1)) ) &
1711	) ) + ( ard(lct(1)+1) * &
1712	( ( cur_r - lrd(lct(1)) ) / &
1713	( lrd(lct(1)+1) - lrd(lct(1)) ) ) )
1714	ENDIF
1715
1716	!
1717	!-- In Fortran radian instead of degree is used as unit for all
1718	!-- angles. Therefore, a transformation from angles given in
1719	!-- degree to angles given in radian is necessary here:
1720	alpha_attack(rseg) = alpha_attack(rseg) * &
1721	( (2.0_wp*pi) / 360.0_wp )
1722	!
1723	!-- Substraction of the local pitch angle to obtain the local
1724	!-- angle of attack:
1725	alpha_attack(rseg) = phi_rel(rseg) - alpha_attack(rseg)
1726	!
1727	!-- Preliminary transformation back from angles given in radian
1728	!-- to angles given in degree:
1729	alpha_attack(rseg) = alpha_attack(rseg) * &
1730	( 360.0_wp / (2.0_wp*pi) )
1731	!
1732	!-- Correct with collective pitch angle:
1733	alpha_attack = alpha_attack + pitch_add(inot)
1734
1735	!
1736	!-- Determination of the magnitude of the flow velocity relative
1737	!-- to the rotor:
1738	vrel(rseg) = SQRT( u_rot**2 + &
1739	( omega_rot(inot) * cur_r - &
1740	vtheta(rseg) )**2 )
1741
1742	!
1743	!-- !-----------------------------------------------------------!
1744	!-- !-- Interpolation of chord as well as lift and drag --!
1745	!-- !-- coefficients from tabulated values --!
1746	!-- !-----------------------------------------------------------!
1747
1748	!
1749	!-- Interpolation of the chord_length from tabulated values to
1750	!-- the current radial position:
1751
1752	IF (cur_r == 0.0_wp) THEN
1753	chord(rseg) = 0.0_wp
1754	ELSE IF (cur_r >= lrd(size(crd))) THEN
1755	chord(rseg) = (crd(size(crd)) + ard(size(crd)-1)) / 2.0_wp
1756	ELSE
1757	chord(rseg) = ( crd(lct(1)) * &
1758	( ( lrd(lct(1)+1) - cur_r ) / &
1759	( lrd(lct(1)+1) - lrd(lct(1)) ) ) ) + &
1760	( crd(lct(1)+1) * &
1761	( ( cur_r-lrd(lct(1)) ) / &
1762	( lrd(lct(1)+1) - lrd(lct(1)) ) ) )
1763	ENDIF
1764
1765	!
1766	!-- Determine index of current angle of attack, needed for
1767	!-- finding the appropriate interpolated values of the lift and
1768	!-- drag coefficients (-180.0 degrees = 0, +180.0 degrees = 36000,
1769	!-- so one index every 0.01 degrees):
1770	iialpha = CEILING( ( alpha_attack(rseg) + 180.0_wp ) &
1771	* ( 1.0_wp / accu_cl_cd_tab ) )
1772	!
1773	!-- Determine index of current radial position, needed for
1774	!-- finding the appropriate interpolated values of the lift and
1775	!-- drag coefficients (one index every 0.1 m):
1776	iir = CEILING( cur_r * 10.0_wp )
1777	!
1778	!-- Read in interpolated values of the lift and drag coefficients
1779	!-- for the current radial position and angle of attack:
1780	turb_cl(rseg) = turb_cl_tab(iialpha,iir)
1781	turb_cd(rseg) = turb_cd_tab(iialpha,iir)
1782
1783	!
1784	!-- Final transformation back from angles given in degree to
1785	!-- angles given in radian:
1786	alpha_attack(rseg) = alpha_attack(rseg) * &
1787	( (2.0_wp*pi) / 360.0_wp )
1788
1789	!
1790	!-- !-----------------------------------------------------!
1791	!-- !-- Calculation of the forces --!
1792	!-- !-----------------------------------------------------!
1793
1794	!
1795	!-- Calculate the pre_factor for the thrust and torque forces:
1796
1797	pre_factor = 0.5_wp * (vrel(rseg)*2) 3.0_wp * &
1798	chord(rseg) * delta_r(inot) / nsegs(ring,inot)
1799
1800	!
1801	!-- Calculate the thrust force (x-component of the total force)
1802	!-- for each ring segment:
1803	thrust_seg(rseg) = pre_factor * &
1804	( turb_cl(rseg) * COS(phi_rel(rseg)) + &
1805	turb_cd(rseg) * SIN(phi_rel(rseg)) )
1806
1807	!
1808	!-- Determination of the second of the additional forces acting
1809	!-- on the flow in the azimuthal direction: force vector as basis
1810	!-- for torque (torque itself would be the vector product of the
1811	!-- radius vector and the force vector):
1812	torque_seg = pre_factor * &
1813	( turb_cl(rseg) * SIN(phi_rel(rseg)) - &
1814	turb_cd(rseg) * COS(phi_rel(rseg)) )
1815	!
1816	!-- Decomposition of the force vector into two parts:
1817	!-- One acting along the y-direction and one acting along the
1818	!-- z-direction of the rotor coordinate system:
1819
1820	torque_seg_y(rseg) = -torque_seg * sin_rot
1821	torque_seg_z(rseg) = torque_seg * cos_rot
1822
1823	!
1824	!-- Add the segment thrust to the thrust of the whole rotor
1825	thrust_rotor(inot) = thrust_rotor(inot) + &
1826	thrust_seg(rseg)
1827
1828
1829	torque_total(inot) = torque_total(inot) + (torque_seg * cur_r)
1830
1831	ENDDO !-- end of loop over ring segments
1832
1833	!
1834	!-- Restore the forces into arrays containing all the segments of
1835	!-- each ring:
1836	thrust_ring(ring,:) = thrust_seg(:)
1837	torque_ring_y(ring,:) = torque_seg_y(:)
1838	torque_ring_z(ring,:) = torque_seg_z(:)
1839
1840
1841	ENDDO !-- end of loop over rings
1842
1843
1844	CALL cpu_log( log_point_s(62), 'wtm_controller', 'start' )
1845
1846
1847	IF ( speed_control ) THEN
1848	!
1849	!-- Calculation of the current generator speed for rotor speed control
1850
1851	!
1852	!-- The acceleration of the rotor speed is calculated from
1853	!-- the force balance of the accelerating torque
1854	!-- and the torque of the rotating rotor and generator
1855	om_rate = ( torque_total(inot) * air_dens * gear_eff - &
1856	gear_ratio * torque_gen_old(inot) ) / &
1857	( inertia_rot + &
1858	gear_ratio * gear_ratio * inertia_gen ) * dt_3d
1859
1860	!
1861	!-- The generator speed is given by the product of gear gear_ratio
1862	!-- and rotor speed
1863	omega_gen(inot) = gear_ratio * ( omega_rot(inot) + om_rate )
1864
1865	ENDIF
1866
1867	IF ( pitch_control ) THEN
1868
1869	!
1870	!-- If the current generator speed is above rated, the pitch is not
1871	!-- saturated and the change from the last time step is within the
1872	!-- maximum pitch rate, then the pitch loop is repeated with a pitch
1873	!-- gain
1874	IF ( ( omega_gen(inot) > rated_genspeed ) .AND. &
1875	( pitch_add(inot) < 25.0_wp ) .AND. &
1876	( pitch_add(inot) < pitch_add_old(inot) + &
1877	pitch_rate * dt_3d ) ) THEN
1878	pitch_sw = .TRUE.
1879	!
1880	!-- Go back to beginning of pit_loop
1881	CYCLE pit_loop
1882	ENDIF
1883
1884	!
1885	!-- The current pitch is saved for the next time step
1886	pitch_add_old(inot) = pitch_add(inot)
1887	pitch_sw = .FALSE.
1888	ENDIF
1889	EXIT pit_loop
1890	ENDDO pit_loop ! Recursive pitch control loop
1891
1892
1893	!
1894	!-- Call the rotor speed controller
1895
1896	IF ( speed_control ) THEN
1897	!
1898	!-- Find processor at i_hub, j_hub
1899	IF ( ( nxl <= i_hub(inot) ) .AND. ( nxr >= i_hub(inot) ) ) &
1900	THEN
1901	IF ( ( nys <= j_hub(inot) ) .AND. ( nyn >= j_hub(inot) ) )&
1902	THEN
1903	CALL wtm_speed_control( inot )
1904	ENDIF
1905	ENDIF
1906
1907	ENDIF
1908
1909
1910	CALL cpu_log( log_point_s(62), 'wtm_controller', 'stop' )
1911
1912	CALL cpu_log( log_point_s(63), 'wtm_smearing', 'start' )
1913
1914
1915	!-- !-----------------------------------------------------------------!
1916	!-- !-- Regularization kernel --!
1917	!-- !-- Smearing of the forces and interpolation to cartesian grid --!
1918	!-- !-----------------------------------------------------------------!
1919	!
1920	!-- The aerodynamic blade forces need to be distributed smoothly on
1921	!-- several mesh points in order to avoid singular behaviour
1922	!
1923	!-- Summation over sum of weighted forces. The weighting factor
1924	!-- (calculated in user_init) includes information on the distance
1925	!-- between the center of the grid cell and the rotor segment under
1926	!-- consideration
1927	!
1928	!-- To save computing time, apply smearing only for the relevant part
1929	!-- of the model domain:
1930	!
1931	!--
1932	!-- Calculation of the boundaries:
1933	i_smear(inot) = CEILING( ( rr(inot) * ABS( roty(inot,1) ) + &
1934	eps_min ) / dx )
1935	j_smear(inot) = CEILING( ( rr(inot) * ABS( roty(inot,2) ) + &
1936	eps_min ) / dy )
1937
1938	DO i = MAX( nxl, i_hub(inot) - i_smear(inot) ), &
1939	MIN( nxr, i_hub(inot) + i_smear(inot) )
1940	DO j = MAX( nys, j_hub(inot) - j_smear(inot) ), &
1941	MIN( nyn, j_hub(inot) + j_smear(inot) )
1942	DO k = MAX( nzb_u_inner(j,i)+1, k_hub(inot) - k_smear(inot) ), &
1943	k_hub(inot) + k_smear(inot)
1944	DO ring = 1, nrings(inot)
1945	DO rseg = 1, nsegs(ring,inot)
1946	!
1947	!-- Determine the square of the distance between the
1948	!-- current grid point and each rotor area segment:
1949	dist_u_3d = ( i * dx - rbx(ring,rseg) )**2 + &
1950	( j * dy + 0.5_wp * dy - rby(ring,rseg) )**2 + &
1951	( k * dz - 0.5_wp * dz - rbz(ring,rseg) )**2
1952	dist_v_3d = ( i * dx + 0.5_wp * dx - rbx(ring,rseg) )**2 + &
1953	( j * dy - rby(ring,rseg) )**2 + &
1954	( k * dz - 0.5_wp * dz - rbz(ring,rseg) )**2
1955	dist_w_3d = ( i * dx + 0.5_wp * dx - rbx(ring,rseg) )**2 + &
1956	( j * dy + 0.5_wp * dy - rby(ring,rseg) )**2 + &
1957	( k * dz - rbz(ring,rseg) )**2
1958
1959	!
1960	!-- 3D-smearing of the forces with a polynomial function
1961	!-- (much faster than the old Gaussian function), using
1962	!-- some parameters that have been calculated in user_init.
1963	!-- The function is only similar to Gaussian function for
1964	!-- squared distances <= eps_min2:
1965	IF ( dist_u_3d <= eps_min2 ) THEN
1966	thrust(k,j,i) = thrust(k,j,i) + &
1967	thrust_ring(ring,rseg) * &
1968	( ( pol_a * dist_u_3d - pol_b ) * &
1969	dist_u_3d + 1.0_wp ) * eps_factor
1970	ENDIF
1971	IF ( dist_v_3d <= eps_min2 ) THEN
1972	torque_y(k,j,i) = torque_y(k,j,i) + &
1973	torque_ring_y(ring,rseg) * &
1974	( ( pol_a * dist_v_3d - pol_b ) *&
1975	dist_v_3d + 1.0_wp ) * eps_factor
1976	ENDIF
1977	IF ( dist_w_3d <= eps_min2 ) THEN
1978	torque_z(k,j,i) = torque_z(k,j,i) + &
1979	torque_ring_z(ring,rseg) * &
1980	( ( pol_a * dist_w_3d - pol_b ) *&
1981	dist_w_3d + 1.0_wp ) * eps_factor
1982	ENDIF
1983
1984	ENDDO ! End of loop over rseg
1985	ENDDO ! End of loop over ring
1986
1987	!
1988	!-- Rotation of force components:
1989	rot_tend_x(k,j,i) = rot_tend_x(k,j,i) + &
1990	thrust(k,j,i)*rotx(inot,1) + &
1991	torque_y(k,j,i)*roty(inot,1) + &
1992	torque_z(k,j,i)*rotz(inot,1)
1993
1994	rot_tend_y(k,j,i) = rot_tend_y(k,j,i) + &
1995	thrust(k,j,i)*rotx(inot,2) + &
1996	torque_y(k,j,i)*roty(inot,2) + &
1997	torque_z(k,j,i)*rotz(inot,2)
1998
1999	rot_tend_z(k,j,i) = rot_tend_z(k,j,i) + &
2000	thrust(k,j,i)*rotx(inot,3) + &
2001	torque_y(k,j,i)*roty(inot,3) + &
2002	torque_z(k,j,i)*rotz(inot,3)
2003
2004	ENDDO ! End of loop over k
2005	ENDDO ! End of loop over j
2006	ENDDO ! End of loop over i
2007
2008	CALL cpu_log( log_point_s(63), 'wtm_smearing', 'stop' )
2009
2010	ENDDO !-- end of loop over turbines
2011
2012
2013	IF ( yaw_control ) THEN
2014	!
2015	!-- Allocate arrays for yaw control at first call
2016	!-- Can't be allocated before dt_3d is set
2017	IF ( start_up ) THEN
2018	WDLON = NINT( 30.0_wp / dt_3d ) ! 30s running mean array
2019	ALLOCATE( wd30(1:nturbines,1:WDLON) )
2020	wd30 = 999.0_wp ! Set to dummy value
2021	ALLOCATE( wd30_l(1:WDLON) )
2022
2023	WDSHO = NINT( 2.0_wp / dt_3d ) ! 2s running mean array
2024	ALLOCATE( wd2(1:nturbines,1:WDSHO) )
2025	wd2 = 999.0_wp ! Set to dummy value
2026	ALLOCATE( wd2_l(1:WDSHO) )
2027	start_up = .FALSE.
2028	ENDIF
2029
2030	!
2031	!-- Calculate the inflow wind speed
2032	!--
2033	!-- Loop over number of turbines:
2034	DO inot = 1, nturbines
2035	!
2036	!-- Find processor at i_hub, j_hub
2037	IF ( ( nxl <= i_hub(inot) ) .AND. ( nxr >= i_hub(inot) ) ) &
2038	THEN
2039	IF ( ( nys <= j_hub(inot) ) .AND. ( nyn >= j_hub(inot) ) )&
2040	THEN
2041
2042	u_inflow_l(inot) = u(k_hub(inot),j_hub(inot),i_hub(inot))
2043
2044	wdir_l(inot) = -1.0_wp * ATAN2( &
2045	0.5_wp * ( v(k_hub(inot),j_hub(inot),i_hub(inot)+1) + &
2046	v(k_hub(inot),j_hub(inot),i_hub(inot)) ) , &
2047	0.5_wp * ( u(k_hub(inot),j_hub(inot)+1,i_hub(inot)) + &
2048	u(k_hub(inot),j_hub(inot),i_hub(inot)) ) )
2049
2050	CALL wtm_yawcontrol( inot )
2051
2052	phi_yaw_l(inot) = phi_yaw(inot)
2053
2054	ENDIF
2055	ENDIF
2056
2057	ENDDO !-- end of loop over turbines
2058
2059	!
2060	!-- Transfer of information to the other cpus
2061	CALL MPI_ALLREDUCE( u_inflow_l, u_inflow, nturbines, MPI_REAL, &
2062	MPI_SUM, comm2d, ierr )
2063	CALL MPI_ALLREDUCE( wdir_l, wdir, nturbines, MPI_REAL, MPI_SUM, &
2064	comm2d, ierr )
2065	CALL MPI_ALLREDUCE( phi_yaw_l, phi_yaw, nturbines, MPI_REAL, &
2066	MPI_SUM, comm2d, ierr )
2067
2068	DO inot = 1, nturbines
2069	!
2070	!-- Update rotor orientation
2071	CALL wtm_rotate_rotor( inot )
2072
2073	ENDDO ! End of loop over turbines
2074
2075	END IF
2076
2077	IF ( speed_control ) THEN
2078	!
2079	!-- Transfer of information to the other cpus
2080	! CALL MPI_ALLREDUCE( omega_gen, omega_gen_old, nturbines, &
2081	! MPI_REAL,MPI_SUM, comm2d, ierr )
2082	CALL MPI_ALLREDUCE( torque_gen, torque_gen_old, nturbines, &
2083	MPI_REAL, MPI_SUM, comm2d, ierr )
2084	CALL MPI_ALLREDUCE( omega_rot_l, omega_rot, nturbines, &
2085	MPI_REAL, MPI_SUM, comm2d, ierr )
2086	CALL MPI_ALLREDUCE( omega_gen_f, omega_gen_f_old, nturbines, &
2087	MPI_REAL, MPI_SUM, comm2d, ierr )
2088
2089	ENDIF
2090
2091	DO inot = 1, nturbines
2092
2093	IF ( myid == 0 ) THEN
2094	IF ( openfile_turb_mod(400+inot)%opened ) THEN
2095	WRITE ( 400+inot, 106 ) simulated_time, omega_rot(inot), &
2096	omega_gen(inot), torque_gen_old(inot), &
2097	torque_total(inot), pitch_add(inot), &
2098	torque_gen_old(inot)omega_gen(inot)gen_eff, &
2099	torque_total(inot)omega_rot(inot)air_dens, &
2100	thrust_rotor(inot), &
2101	wdir(inot)*180.0_wp/pi, &
2102	(phi_yaw(inot))*180.0_wp/pi
2103
2104	ELSE
2105
2106	WRITE ( turbine_id,'(I2.2)') inot
2107	OPEN ( 400+inot, FILE=( 'TURBINE_PARAMETERS'//turbine_id ), &
2108	FORM='FORMATTED' )
2109	WRITE ( 400+inot, 105 ) inot
2110	WRITE ( 400+inot, 106 ) simulated_time, omega_rot(inot), &
2111	omega_gen(inot), torque_gen_old(inot), &
2112	torque_total(inot), pitch_add(inot), &
2113	torque_gen_old(inot)omega_gen(inot)gen_eff, &
2114	torque_total(inot)omega_rot(inot)air_dens, &
2115	thrust_rotor(inot), &
2116	wdir(inot)*180.0_wp/pi, &
2117	(phi_yaw(inot))*180.0_wp/pi
2118	ENDIF
2119	ENDIF
2120
2121	!-- Set open flag
2122	openfile_turb_mod(400+inot)%opened = .TRUE.
2123	ENDDO !-- end of loop over turbines
2124
2125	ENDIF
2126
2127	CALL cpu_log( log_point_s(61), 'wtm_forces', 'stop' )
2128
2129	!
2130	!-- Formats
2131	105 FORMAT ('Turbine control data for turbine ',I2,1X,':'/ &
2132	&'----------------------------------------'/ &
2133	&' Time RSpeed GSpeed ', &
2134	'GenTorque AeroTorque Pitch Power(Gen) Power(Rot) ', &
2135	'RotThrust WDirection YawOrient')
2136
2137	106 FORMAT (F9.3,2X,F7.3,2X,F7.2,2X,F9.1,3X,F9.1,1X,F6.2,2X,F10.1,2X, &
2138	F10.1,1X,F9.1,2X,F7.2,1X,F7.2)
2139
2140
2141	END SUBROUTINE wtm_forces
2142
2143
2144	!------------------------------------------------------------------------------!
2145	! Description:
2146	! ------------
2147	!> Yaw controller for the wind turbine model
2148	!------------------------------------------------------------------------------!
2149	SUBROUTINE wtm_yawcontrol( inot )
2150
2151	USE constants
2152	USE kinds
2153
2154	IMPLICIT NONE
2155
2156	INTEGER(iwp) :: inot
2157	INTEGER(iwp) :: i_wd_30
2158	REAL(wp) :: missal
2159
2160	i_wd_30 = 0_iwp
2161
2162	!
2163	!-- The yaw controller computes a 30s running mean of the wind direction.
2164	!-- If the difference between turbine alignment and wind direction exceeds
2165	!-- 5Â°, the turbine is yawed. The mechanism stops as soon as the 2s-running
2166	!-- mean of the missalignment is smaller than 0.5Â°.
2167	!-- Attention: If the timestep during the simulation changes significantly
2168	!-- the lengths of the running means change and it does not correspond to
2169	!-- 30s/2s anymore.
2170	!-- ! Needs to be modified for these situations !
2171	!-- For wind from the east, the averaging of the wind direction could cause
2172	!-- problems and the yaw controller is probably flawed. -> Routine for
2173	!-- averaging needs to be improved!
2174	!
2175	!-- Check if turbine is not yawing
2176	IF ( .NOT. doyaw(inot) ) THEN
2177	!
2178	!-- Write current wind direction into array
2179	wd30_l = wd30(inot,:)
2180	wd30_l = CSHIFT( wd30_l, SHIFT=-1 )
2181	wd30_l(1) = wdir(inot)
2182	!
2183	!-- Check if array is full ( no more dummies )
2184	IF ( .NOT. ANY( wd30_l == 999.) ) THEN
2185
2186	missal = SUM( wd30_l ) / SIZE( wd30_l ) - phi_yaw(inot)
2187	!
2188	!-- Check if turbine is missaligned by more than max_miss
2189	IF ( ABS( missal ) > max_miss ) THEN
2190	!
2191	!-- Check in which direction to yaw
2192	yawdir(inot) = SIGN( 1.0_wp, missal )
2193	!
2194	!-- Start yawing of turbine
2195	phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d
2196	doyaw(inot) = .TRUE.
2197	wd30_l = 999. ! fill with dummies again
2198	ENDIF
2199	ENDIF
2200
2201	wd30(inot,:) = wd30_l
2202
2203	!
2204	!-- If turbine is already yawing:
2205	!-- Initialize 2 s running mean and yaw until the missalignment is smaller
2206	!-- than min_miss
2207
2208	ELSE
2209	!
2210	!-- Initialize 2 s running mean
2211	wd2_l = wd2(inot,:)
2212	wd2_l = CSHIFT( wd2_l, SHIFT = -1 )
2213	wd2_l(1) = wdir(inot)
2214	!
2215	!-- Check if array is full ( no more dummies )
2216	IF ( .NOT. ANY( wd2_l == 999.0_wp ) ) THEN
2217	!
2218	!-- Calculate missalignment of turbine
2219	missal = SUM( wd2_l - phi_yaw(inot) ) / SIZE( wd2_l )
2220	!
2221	!-- Check if missalignment is still larger than 0.5 degree and if the
2222	!-- yaw direction is still right
2223	IF ( ( ABS( missal ) > min_miss ) .AND. &
2224	( yawdir(inot) == SIGN( 1.0_wp, missal ) ) ) THEN
2225	!
2226	!-- Continue yawing
2227	phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d
2228	ELSE
2229	!
2230	!-- Stop yawing
2231	doyaw(inot) = .FALSE.
2232	wd2_l = 999.0_wp ! fill with dummies again
2233	ENDIF
2234	ELSE
2235	!
2236	!-- Continue yawing
2237	phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d
2238	ENDIF
2239
2240	wd2(inot,:) = wd2_l
2241
2242	ENDIF
2243
2244	END SUBROUTINE wtm_yawcontrol
2245
2246
2247	!------------------------------------------------------------------------------!
2248	! Description:
2249	! ------------
2250	!> Initialization of the speed control
2251	!------------------------------------------------------------------------------!
2252	SUBROUTINE wtm_init_speed_control
2253
2254
2255	IMPLICIT NONE
2256
2257	!
2258	!-- If speed control is set, remaining variables and control_parameters for
2259	!-- the control algorithm are calculated
2260	!
2261	!-- Calculate slope constant for region 15
2262	slope15 = ( slope2 * min_reg2 * min_reg2 ) / ( min_reg2 - min_reg15 )
2263	!
2264	!-- Calculate upper limit of slipage region
2265	vs_sysp = rated_genspeed / 1.1_wp
2266	!
2267	!-- Calculate slope of slipage region
2268	slope25 = ( rated_power / rated_genspeed ) / &
2269	( rated_genspeed - vs_sysp )
2270	!
2271	!-- Calculate lower limit of slipage region
2272	min_reg25 = ( slope25 - SQRT( slope25 * ( slope25 - 4.0_wp * &
2273	slope2 * vs_sysp ) ) ) / &
2274	( 2.0_wp * slope2 )
2275	!
2276	!-- Frequency for the simple low pass filter
2277	Fcorner = 0.25_wp
2278	!
2279	!-- At the first timestep the torque is set to its maximum to prevent
2280	!-- an overspeeding of the rotor
2281	torque_gen_old(:) = max_torque_gen
2282
2283	END SUBROUTINE wtm_init_speed_control
2284
2285
2286	!------------------------------------------------------------------------------!
2287	! Description:
2288	! ------------
2289	!> Simple controller for the regulation of the rotor speed
2290	!------------------------------------------------------------------------------!
2291	SUBROUTINE wtm_speed_control( inot )
2292
2293
2294	IMPLICIT NONE
2295
2296	INTEGER(iwp) :: inot
2297
2298
2299
2300	!
2301	!-- The controller is based on the fortran script from Jonkman
2302	!-- et al. 2009 "Definition of a 5 MW Reference Wind Turbine for
2303	!-- offshore system developement"
2304
2305	!
2306	!-- The generator speed is filtered by a low pass filter
2307	!-- for the control of the generator torque
2308	lp_coeff = EXP( -2.0_wp * 3.14_wp * dt_3d * Fcorner )
2309	omega_gen_f(inot) = ( 1.0_wp - lp_coeff ) * omega_gen(inot) + lp_coeff *&
2310	omega_gen_f_old(inot)
2311
2312	IF ( omega_gen_f(inot) <= min_reg15 ) THEN
2313	!
2314	!-- Region 1: Generator torque is set to zero to accelerate the rotor:
2315	torque_gen(inot) = 0
2316
2317	ELSEIF ( omega_gen_f(inot) <= min_reg2 ) THEN
2318	!
2319	!-- Region 1.5: Generator torque is increasing linearly with rotor speed:
2320	torque_gen(inot) = slope15 * ( omega_gen_f(inot) - min_reg15 )
2321
2322	ELSEIF ( omega_gen_f(inot) <= min_reg25 ) THEN
2323	!
2324	!-- Region 2: Generator torque is increased by the square of the generator
2325	!-- speed to keep the TSR optimal:
2326	torque_gen(inot) = slope2 * omega_gen_f(inot) * omega_gen_f(inot)
2327
2328	ELSEIF ( omega_gen_f(inot) < rated_genspeed ) THEN
2329	!
2330	!-- Region 2.5: Slipage region between 2 and 3:
2331	torque_gen(inot) = slope25 * ( omega_gen_f(inot) - vs_sysp )
2332
2333	ELSE
2334	!
2335	!-- Region 3: Generator torque is antiproportional to the rotor speed to
2336	!-- keep the power constant:
2337	torque_gen(inot) = rated_power / omega_gen_f(inot)
2338
2339	ENDIF
2340	!
2341	!-- Calculate torque rate and confine with a max
2342	trq_rate = ( torque_gen(inot) - torque_gen_old(inot) ) / dt_3d
2343	trq_rate = MIN( MAX( trq_rate, -1.0_wp * max_trq_rate ), max_trq_rate )
2344	!
2345	!-- Calculate new gen torque and confine with max torque
2346	torque_gen(inot) = torque_gen_old(inot) + trq_rate * dt_3d
2347	torque_gen(inot) = MIN( torque_gen(inot), max_torque_gen )
2348	!
2349	!-- Overwrite values for next timestep
2350	omega_rot_l(inot) = omega_gen(inot) / gear_ratio
2351
2352
2353	END SUBROUTINE wtm_speed_control
2354
2355
2356	!------------------------------------------------------------------------------!
2357	! Description:
2358	! ------------
2359	!> Application of the additional forces generated by the wind turbine on the
2360	!> flow components (tendency terms)
2361	!> Call for all grid points
2362	!------------------------------------------------------------------------------!
2363	SUBROUTINE wtm_tendencies( component )
2364
2365
2366	IMPLICIT NONE
2367
2368	INTEGER(iwp) :: component !< prognostic variable (u,v,w)
2369	INTEGER(iwp) :: i !< running index
2370	INTEGER(iwp) :: j !< running index
2371	INTEGER(iwp) :: k !< running index
2372
2373
2374	SELECT CASE ( component )
2375
2376	CASE ( 1 )
2377	!
2378	!-- Apply the x-component of the force to the u-component of the flow:
2379	IF ( simulated_time >= time_turbine_on ) THEN
2380	DO i = nxlg, nxrg
2381	DO j = nysg, nyng
2382	DO k = nzb_u_inner(j,i)+1, k_hub(1) + k_smear(1)
2383	!
2384	!-- Calculate the thrust generated by the nacelle and the tower
2385	tend_nac_x = 0.5_wp * nac_cd_surf(k,j,i) * &
2386	SIGN( u(k,j,i)**2 , u(k,j,i) )
2387	tend_tow_x = 0.5_wp * tow_cd_surf(k,j,i) * &
2388	SIGN( u(k,j,i)**2 , u(k,j,i) )
2389
2390	tend(k,j,i) = tend(k,j,i) - rot_tend_x(k,j,i) &
2391	- tend_nac_x - tend_tow_x
2392	ENDDO
2393	ENDDO
2394	ENDDO
2395	ENDIF
2396
2397	CASE ( 2 )
2398	!
2399	!-- Apply the y-component of the force to the v-component of the flow:
2400	IF ( simulated_time >= time_turbine_on ) THEN
2401	DO i = nxlg, nxrg
2402	DO j = nysg, nyng
2403	DO k = nzb_v_inner(j,i)+1, k_hub(1) + k_smear(1)
2404	tend_nac_y = 0.5_wp * nac_cd_surf(k,j,i) * &
2405	SIGN( v(k,j,i)**2 , v(k,j,i) )
2406	tend_tow_y = 0.5_wp * tow_cd_surf(k,j,i) * &
2407	SIGN( v(k,j,i)**2 , v(k,j,i) )
2408	tend(k,j,i) = tend(k,j,i) - rot_tend_y(k,j,i) &
2409	- tend_nac_y - tend_tow_y
2410	ENDDO
2411	ENDDO
2412	ENDDO
2413	ENDIF
2414
2415	CASE ( 3 )
2416	!
2417	!-- Apply the z-component of the force to the w-component of the flow:
2418	IF ( simulated_time >= time_turbine_on ) THEN
2419	DO i = nxlg, nxrg
2420	DO j = nysg, nyng
2421	DO k = nzb_w_inner(j,i)+1, k_hub(1) + k_smear(1)
2422	tend(k,j,i) = tend(k,j,i) - rot_tend_z(k,j,i)
2423	ENDDO
2424	ENDDO
2425	ENDDO
2426	ENDIF
2427
2428
2429	CASE DEFAULT
2430
2431	WRITE( message_string, * ) 'unknown prognostic variable: ', component
2432	CALL message( 'wtm_tendencies', 'PA04??', 1, 2, 0, 6, 0 )
2433
2434	END SELECT
2435
2436
2437	END SUBROUTINE wtm_tendencies
2438
2439
2440	!------------------------------------------------------------------------------!
2441	! Description:
2442	! ------------
2443	!> Application of the additional forces generated by the wind turbine on the
2444	!> flow components (tendency terms)
2445	!> Call for grid point i,j
2446	!------------------------------------------------------------------------------!
2447	SUBROUTINE wtm_tendencies_ij( i, j, component )
2448
2449
2450	IMPLICIT NONE
2451
2452	INTEGER(iwp) :: component !< prognostic variable (u,v,w)
2453	INTEGER(iwp) :: i !< running index
2454	INTEGER(iwp) :: j !< running index
2455	INTEGER(iwp) :: k !< running index
2456
2457	SELECT CASE ( component )
2458
2459	CASE ( 1 )
2460	!
2461	!-- Apply the x-component of the force to the u-component of the flow:
2462	IF ( simulated_time >= time_turbine_on ) THEN
2463
2464	DO k = nzb_u_inner(j,i)+1, k_hub(1) + k_smear(1)
2465	!
2466	!-- Calculate the thrust generated by the nacelle and the tower
2467	tend_nac_x = 0.5_wp * nac_cd_surf(k,j,i) * &
2468	SIGN( u(k,j,i)**2 , u(k,j,i) )
2469	tend_tow_x = 0.5_wp * tow_cd_surf(k,j,i) * &
2470	SIGN( u(k,j,i)**2 , u(k,j,i) )
2471	tend(k,j,i) = tend(k,j,i) - rot_tend_x(k,j,i) &
2472	- tend_nac_x - tend_tow_x
2473	ENDDO
2474	ENDIF
2475
2476	CASE ( 2 )
2477	!
2478	!-- Apply the y-component of the force to the v-component of the flow:
2479	IF ( simulated_time >= time_turbine_on ) THEN
2480	DO k = nzb_v_inner(j,i)+1, k_hub(1) + k_smear(1)
2481	tend_nac_y = 0.5_wp * nac_cd_surf(k,j,i) * &
2482	SIGN( v(k,j,i)**2 , v(k,j,i) )
2483	tend_tow_y = 0.5_wp * tow_cd_surf(k,j,i) * &
2484	SIGN( v(k,j,i)**2 , v(k,j,i) )
2485	tend(k,j,i) = tend(k,j,i) - rot_tend_y(k,j,i) &
2486	- tend_nac_y - tend_tow_y
2487	ENDDO
2488	ENDIF
2489
2490	CASE ( 3 )
2491	!
2492	!-- Apply the z-component of the force to the w-component of the flow:
2493	IF ( simulated_time >= time_turbine_on ) THEN
2494	DO k = nzb_w_inner(j,i)+1, k_hub(1) + k_smear(1)
2495	tend(k,j,i) = tend(k,j,i) - rot_tend_z(k,j,i)
2496	ENDDO
2497	ENDIF
2498
2499
2500	CASE DEFAULT
2501
2502	WRITE( message_string, * ) 'unknown prognostic variable: ', component
2503	CALL message( 'wtm_tendencies', 'PA04??', 1, 2, 0, 6, 0 )
2504
2505	END SELECT
2506
2507
2508	END SUBROUTINE wtm_tendencies_ij
2509
2510	END MODULE wind_turbine_model_mod

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

Download in other formats:

| Impressum | ©Leibniz Universität Hannover |