!> @file wind_turbine_model_mod.f90 !------------------------------------------------------------------------------! ! This file is part of PALM. ! ! PALM is free software: you can redistribute it and/or modify it under the ! terms of the GNU General Public License as published by the Free Software ! Foundation, either version 3 of the License, or (at your option) any later ! version. ! ! PALM is distributed in the hope that it will be useful, but WITHOUT ANY ! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR ! A PARTICULAR PURPOSE. See the GNU General Public License for more details. ! ! You should have received a copy of the GNU General Public License along with ! PALM. If not, see . ! ! Copyright 1997-2017 Leibniz Universitaet Hannover !------------------------------------------------------------------------------! ! ! Current revisions: ! ----------------- ! ! ! Former revisions: ! ----------------- ! $Id: wind_turbine_model_mod.f90 2153 2017-02-17 13:35:52Z suehring $ ! ! 2152 2017-02-17 13:27:24Z lvollmer ! Bugfix in subroutine wtm_read_blade_tables ! Addition of a tip loss model ! ! 2015 2016-09-28 08:45:18Z lvollmer ! Bugfix of pitch control ! ! 2000 2016-08-20 18:09:15Z knoop ! Forced header and separation lines into 80 columns ! ! 1929 2016-06-09 16:25:25Z suehring ! Bugfix: added preprocessor directives for parallel and serial mode ! ! 1914 2016-05-26 14:44:07Z witha ! Initial revision ! ! ! Description: ! ------------ !> This module calculates the effect of wind turbines on the flow fields. The !> initial version contains only the advanced actuator disk with rotation method !> (ADM-R). !> The wind turbines include the tower effect, can be yawed and tilted. !> The wind turbine model includes controllers for rotational speed, pitch and !> yaw. !> Currently some specifications of the NREL 5 MW reference turbine !> are hardcoded whereas most input data comes from separate files (currently !> external, planned to be included as namelist which will be read in !> automatically). !> !> @todo Revise code according to PALM Coding Standard !> @todo Implement ADM and ALM turbine models !> @todo Generate header information !> @todo Implement further parameter checks and error messages !> @todo Revise and add code documentation !> @todo Output turbine parameters as timeseries !> @todo Include additional output variables !> @todo Revise smearing the forces for turbines in yaw !> @todo Revise nacelle and tower parameterization !> @todo Allow different turbine types in one simulation ! !------------------------------------------------------------------------------! MODULE wind_turbine_model_mod USE arrays_3d, & ONLY: dd2zu, tend, u, v, w, zu, zw USE constants USE control_parameters, & ONLY: dt_3d, dz, message_string, simulated_time USE cpulog, & ONLY: cpu_log, log_point_s USE grid_variables, & ONLY: ddx, dx, ddy, dy USE indices, & ONLY: nbgp, nx, nxl, nxlg, nxr, nxrg, ny, nyn, nyng, nys, nysg, nz, & nzb, nzb_u_inner, nzb_v_inner, nzb_w_inner, nzt USE kinds USE pegrid IMPLICIT NONE PRIVATE LOGICAL :: wind_turbine=.FALSE. !< switch for use of wind turbine model ! !-- Variables specified in the namelist wind_turbine_par INTEGER(iwp) :: nairfoils = 8 !< number of airfoils of the used turbine model (for ADM-R and ALM) INTEGER(iwp) :: nturbines = 1 !< number of turbines LOGICAL :: pitch_control = .FALSE. !< switch for use of pitch controller LOGICAL :: speed_control = .FALSE. !< switch for use of speed controller LOGICAL :: yaw_control = .FALSE. !< switch for use of yaw controller LOGICAL :: tl_cor = .FALSE. !< switch for use of tip loss correct. REAL(wp) :: segment_length = 1.0_wp !< length of the segments, the rotor area is divided into !< (in tangential direction, as factor of MIN(dx,dy,dz)) REAL(wp) :: segment_width = 0.5_wp !< width of the segments, the rotor area is divided into !< (in radial direction, as factor of MIN(dx,dy,dz)) REAL(wp) :: time_turbine_on = 0.0_wp !< time at which turbines are started REAL(wp) :: tilt = 0.0_wp !< vertical tilt of the rotor [degree] ( positive = backwards ) REAL(wp), DIMENSION(1:100) :: dtow = 0.0_wp !< tower diameter [m] REAL(wp), DIMENSION(1:100) :: omega_rot = 0.0_wp !< inital or constant rotor speed [rad/s] REAL(wp), DIMENSION(1:100) :: phi_yaw = 0.0_wp !< yaw angle [degree] ( clockwise, 0 = facing west ) REAL(wp), DIMENSION(1:100) :: pitch_add = 0.0_wp !< constant pitch angle REAL(wp), DIMENSION(1:100) :: rcx = 9999999.9_wp !< position of hub in x-direction REAL(wp), DIMENSION(1:100) :: rcy = 9999999.9_wp !< position of hub in y-direction REAL(wp), DIMENSION(1:100) :: rcz = 9999999.9_wp !< position of hub in z-direction REAL(wp), DIMENSION(1:100) :: rnac = 0.0_wp !< nacelle diameter [m] REAL(wp), DIMENSION(1:100) :: rr = 63.0_wp !< rotor radius [m] REAL(wp), DIMENSION(1:100) :: turb_cd_nacelle = 0.85_wp !< drag coefficient for nacelle REAL(wp), DIMENSION(1:100) :: turb_cd_tower = 1.2_wp !< drag coefficient for tower ! !-- Variables specified in the namelist for speed controller !-- Default values are from the NREL 5MW research turbine (Jonkman, 2008) REAL(wp) :: rated_power = 5296610.0_wp !< rated turbine power [W] REAL(wp) :: gear_ratio = 97.0_wp !< Gear ratio from rotor to generator REAL(wp) :: inertia_rot = 34784179.0_wp !< Inertia of the rotor [kg/m2] REAL(wp) :: inertia_gen = 534.116_wp !< Inertia of the generator [kg/m2] REAL(wp) :: gen_eff = 0.944_wp !< Electric efficiency of the generator REAL(wp) :: gear_eff = 1.0_wp !< Loss between rotor and generator REAL(wp) :: air_dens = 1.225_wp !< Air density to convert to W [kg/m3] REAL(wp) :: rated_genspeed = 121.6805_wp !< Rated generator speed [rad/s] REAL(wp) :: max_torque_gen = 47402.91_wp !< Maximum of the generator torque [Nm] REAL(wp) :: slope2 = 2.332287_wp !< Slope constant for region 2 REAL(wp) :: min_reg2 = 91.21091_wp !< Lower generator speed boundary of region 2 [rad/s] REAL(wp) :: min_reg15 = 70.16224_wp !< Lower generator speed boundary of region 1.5 [rad/s] REAL(wp) :: max_trq_rate = 15000.0_wp !< Max generator torque increase [Nm/s] REAL(wp) :: pitch_rate = 8.0_wp !< Max pitch rate [degree/s] ! !-- Variables specified in the namelist for yaw control REAL(wp) :: yaw_speed = 0.005236_wp !< speed of the yaw actuator [rad/s] REAL(wp) :: max_miss = 0.08726_wp !< maximum tolerated yaw missalignment [rad] REAL(wp) :: min_miss = 0.008726_wp !< minimum yaw missalignment for which the actuator stops [rad] ! !-- Set flag for output files TURBINE_PARAMETERS TYPE file_status LOGICAL :: opened, opened_before END TYPE file_status TYPE(file_status), DIMENSION(500) :: openfile_turb_mod = & file_status(.FALSE.,.FALSE.) ! !-- Variables for initialization of the turbine model INTEGER(iwp) :: inot !< turbine loop index (turbine id) INTEGER(iwp) :: nsegs_max !< maximum number of segments (all turbines, required for allocation of arrays) INTEGER(iwp) :: nrings_max !< maximum number of rings (all turbines, required for allocation of arrays) INTEGER(iwp) :: ring !< ring loop index (ring number) INTEGER(iwp) :: rr_int !< INTEGER(iwp) :: upper_end !< INTEGER(iwp), DIMENSION(1) :: lct !< INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: i_hub !< index belonging to x-position of the turbine INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: i_smear !< index defining the area for the smearing of the forces (x-direction) INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: j_hub !< index belonging to y-position of the turbine INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: j_smear !< index defining the area for the smearing of the forces (y-direction) INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: k_hub !< index belonging to hub height INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: k_smear !< index defining the area for the smearing of the forces (z-direction) INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nrings !< number of rings per turbine INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nsegs_total !< total number of segments per turbine INTEGER(iwp), DIMENSION(:,:), ALLOCATABLE :: nsegs !< number of segments per ring and turbine ! !- parameters for the smearing from the rotor to the cartesian grid REAL(wp) :: pol_a !< parameter for the polynomial smearing fct REAL(wp) :: pol_b !< parameter for the polynomial smearing fct REAL(wp) :: delta_t_factor !< REAL(wp) :: eps_factor !< REAL(wp) :: eps_min !< REAL(wp) :: eps_min2 !< REAL(wp) :: sqrt_arg !< ! !-- Variables for the calculation of lift and drag coefficients REAL(wp), DIMENSION(:), ALLOCATABLE :: ard !< REAL(wp), DIMENSION(:), ALLOCATABLE :: crd !< REAL(wp), DIMENSION(:), ALLOCATABLE :: delta_r !< radial segment length REAL(wp), DIMENSION(:), ALLOCATABLE :: lrd !< REAL(wp) :: accu_cl_cd_tab = 0.1_wp !< Accuracy of the interpolation of !< the lift and drag coeff [deg] REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cd_tab !< table of the blade drag coefficient REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cl_tab !< table of the blade lift coefficient REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: nac_cd_surf !< 3d field of the tower drag coefficient REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: tow_cd_surf !< 3d field of the nacelle drag coefficient ! !-- Variables for the calculation of the forces REAL(wp) :: cur_r !< REAL(wp) :: delta_t !< tangential segment length REAL(wp) :: phi_rotor !< REAL(wp) :: pre_factor !< REAL(wp) :: torque_seg !< REAL(wp) :: u_int_l !< REAL(wp) :: u_int_u !< REAL(wp) :: u_rot !< REAL(wp) :: v_int_l !< REAL(wp) :: v_int_u !< REAL(wp) :: w_int_l !< REAL(wp) :: w_int_u !< ! !- Tendencies from the nacelle and tower thrust REAL(wp) :: tend_nac_x = 0.0_wp !< REAL(wp) :: tend_tow_x = 0.0_wp !< REAL(wp) :: tend_nac_y = 0.0_wp !< REAL(wp) :: tend_tow_y = 0.0_wp !< REAL(wp), DIMENSION(:), ALLOCATABLE :: alpha_attack !< REAL(wp), DIMENSION(:), ALLOCATABLE :: chord !< REAL(wp), DIMENSION(:), ALLOCATABLE :: omega_gen !< curr. generator speed REAL(wp), DIMENSION(:), ALLOCATABLE :: phi_rel !< REAL(wp), DIMENSION(:), ALLOCATABLE :: pitch_add_old!< REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_total !< REAL(wp), DIMENSION(:), ALLOCATABLE :: thrust_rotor !< REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl !< REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd !< REAL(wp), DIMENSION(:), ALLOCATABLE :: vrel !< REAL(wp), DIMENSION(:), ALLOCATABLE :: vtheta !< REAL(wp), DIMENSION(:,:), ALLOCATABLE :: rbx, rby, rbz !< coordinates of the blade elements REAL(wp), DIMENSION(:,:), ALLOCATABLE :: rotx, roty, rotz !< normal vectors to the rotor coordinates ! !- Fields for the interpolation of velocities on the rotor grid REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: u_int !< REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: u_int_1_l !< REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: v_int !< REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: v_int_1_l !< REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: w_int !< REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: w_int_1_l !< ! !- rotor tendencies on the segments REAL(wp), DIMENSION(:), ALLOCATABLE :: thrust_seg !< REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_seg_y !< REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_seg_z !< ! !- rotor tendencies on the rings REAL(wp), DIMENSION(:,:), ALLOCATABLE :: thrust_ring !< REAL(wp), DIMENSION(:,:), ALLOCATABLE :: torque_ring_y !< REAL(wp), DIMENSION(:,:), ALLOCATABLE :: torque_ring_z !< ! !- rotor tendencies on rotor grids for all turbines REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: thrust !< REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: torque_y !< REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: torque_z !< ! !- rotor tendencies on coordinate grid REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_x !< REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_y !< REAL(wp), DIMENSION(:,:,:), ALLOCATABLE :: rot_tend_z !< ! !- variables for the rotation of the rotor coordinates REAL(wp), DIMENSION(1:100,1:3,1:3) :: rot_coord_trans !< matrix for rotation of rotor coordinates REAL(wp), DIMENSION(1:3) :: rot_eigen_rad !< REAL(wp), DIMENSION(1:3) :: rot_eigen_azi !< REAL(wp), DIMENSION(1:3) :: rot_eigen_nor !< REAL(wp), DIMENSION(1:3) :: re !< REAL(wp), DIMENSION(1:3) :: rea !< REAL(wp), DIMENSION(1:3) :: ren !< REAL(wp), DIMENSION(1:3) :: rote !< REAL(wp), DIMENSION(1:3) :: rota !< REAL(wp), DIMENSION(1:3) :: rotn !< ! !-- Fixed variables for the speed controller LOGICAL :: start_up = .TRUE. !< REAL(wp) :: Fcorner !< corner freq for the controller low pass filter REAL(wp) :: min_reg25 !< min region 2.5 REAL(wp) :: om_rate !< rotor speed change REAL(wp) :: slope15 !< slope in region 1.5 REAL(wp) :: slope25 !< slope in region 2.5 REAL(wp) :: trq_rate !< torque change REAL(wp) :: vs_sysp !< REAL(wp) :: lp_coeff !< coeff for the controller low pass filter REAL(wp), DIMENSION(:), ALLOCATABLE :: omega_gen_old !< last gen. speed REAL(wp), DIMENSION(:), ALLOCATABLE :: omega_gen_f !< filtered gen. sp REAL(wp), DIMENSION(:), ALLOCATABLE :: omega_gen_f_old !< last filt. gen. sp REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_gen !< generator torque REAL(wp), DIMENSION(:), ALLOCATABLE :: torque_gen_old !< last gen. torque REAL(wp), DIMENSION(100) :: omega_rot_l = 0.0_wp !< local rot speed [rad/s] ! !-- Fixed variables for the yaw controller REAL(wp), DIMENSION(:) , ALLOCATABLE :: yawdir !< direction to yaw REAL(wp), DIMENSION(:) , ALLOCATABLE :: phi_yaw_l !< local (cpu) yaw angle REAL(wp), DIMENSION(:) , ALLOCATABLE :: wd30_l !< local (cpu) long running avg of the wd REAL(wp), DIMENSION(:) , ALLOCATABLE :: wd2_l !< local (cpu) short running avg of the wd REAL(wp), DIMENSION(:) , ALLOCATABLE :: wdir !< wind direction at hub REAL(wp), DIMENSION(:) , ALLOCATABLE :: u_inflow !< wind speed at hub REAL(wp), DIMENSION(:) , ALLOCATABLE :: wdir_l !< REAL(wp), DIMENSION(:) , ALLOCATABLE :: u_inflow_l !< REAL(wp), DIMENSION(:,:), ALLOCATABLE :: wd30 !< REAL(wp), DIMENSION(:,:), ALLOCATABLE :: wd2 !< LOGICAL, DIMENSION(1:100) :: doyaw = .FALSE. !< INTEGER(iwp) :: WDLON !< INTEGER(iwp) :: WDSHO !< SAVE INTERFACE wtm_parin MODULE PROCEDURE wtm_parin END INTERFACE wtm_parin INTERFACE wtm_check_parameters MODULE PROCEDURE wtm_check_parameters END INTERFACE wtm_check_parameters INTERFACE wtm_init_arrays MODULE PROCEDURE wtm_init_arrays END INTERFACE wtm_init_arrays INTERFACE wtm_init MODULE PROCEDURE wtm_init END INTERFACE wtm_init INTERFACE wtm_read_blade_tables MODULE PROCEDURE wtm_read_blade_tables END INTERFACE wtm_read_blade_tables INTERFACE wtm_forces MODULE PROCEDURE wtm_forces MODULE PROCEDURE wtm_yawcontrol END INTERFACE wtm_forces INTERFACE wtm_rotate_rotor MODULE PROCEDURE wtm_rotate_rotor END INTERFACE wtm_rotate_rotor INTERFACE wtm_speed_control MODULE PROCEDURE wtm_init_speed_control MODULE PROCEDURE wtm_speed_control END INTERFACE wtm_speed_control INTERFACE wtm_tendencies MODULE PROCEDURE wtm_tendencies MODULE PROCEDURE wtm_tendencies_ij END INTERFACE wtm_tendencies PUBLIC wtm_check_parameters, wtm_forces, wtm_init, wtm_init_arrays, & wtm_parin, wtm_tendencies, wtm_tendencies_ij, wind_turbine CONTAINS !------------------------------------------------------------------------------! ! Description: ! ------------ !> Parin for &wind_turbine_par for wind turbine model !------------------------------------------------------------------------------! SUBROUTINE wtm_parin IMPLICIT NONE INTEGER(iwp) :: ierrn !< CHARACTER (LEN=80) :: line !< dummy string that contains the current line of the parameter file NAMELIST /wind_turbine_par/ air_dens, dtow, gear_eff, gear_ratio, & gen_eff, inertia_gen, inertia_rot, max_miss, & max_torque_gen, max_trq_rate, min_miss, & min_reg15, min_reg2, nairfoils, nturbines, & omega_rot, phi_yaw, pitch_add, pitch_control,& rated_genspeed, rated_power, rcx, rcy, rcz, & rnac, rr, segment_length, segment_width, & slope2, speed_control, tilt, time_turbine_on,& turb_cd_nacelle, turb_cd_tower, & yaw_control, yaw_speed, tl_cor ! !-- Try to find wind turbine model package REWIND ( 11 ) line = ' ' DO WHILE ( INDEX( line, '&wind_turbine_par' ) == 0 ) READ ( 11, '(A)', END=10 ) line ENDDO BACKSPACE ( 11 ) ! !-- Read user-defined namelist READ ( 11, wind_turbine_par, IOSTAT=ierrn ) IF ( ierrn < 0 ) THEN message_string = 'errors in \$wind_turbine_par' CALL message( 'wtm_parin', 'PA0???', 1, 2, 0, 6, 0 ) ENDIF ! !-- Set flag that indicates that the wind turbine model is switched on wind_turbine = .TRUE. 10 CONTINUE ! TBD Change from continue, mit ierrn machen END SUBROUTINE wtm_parin SUBROUTINE wtm_check_parameters IMPLICIT NONE IF ( ( .NOT.speed_control ) .AND. pitch_control ) THEN message_string = 'pitch_control = .TRUE. requires '// & 'speed_control = .TRUE.' CALL message( 'wtm_check_parameters', 'PA0???', 1, 2, 0, 6, 0 ) ENDIF IF ( ANY( omega_rot(1:nturbines) <= 0.0 ) ) THEN message_string = 'omega_rot <= 0.0, Please set omega_rot to ' // & 'a value larger than zero' CALL message( 'wtm_check_parameters', 'PA0???', 1, 2, 0, 6, 0 ) ENDIF IF ( ANY( rcx(1:nturbines) == 9999999.9_wp ) .OR. & ANY( rcy(1:nturbines) == 9999999.9_wp ) .OR. & ANY( rcz(1:nturbines) == 9999999.9_wp ) ) THEN message_string = 'rcx, rcy, rcz ' // & 'have to be given for each turbine.' CALL message( 'wtm_check_parameters', 'PA0???', 1, 2, 0, 6, 0 ) ENDIF END SUBROUTINE wtm_check_parameters !------------------------------------------------------------------------------! ! Description: ! ------------ !> Allocate wind turbine model arrays !------------------------------------------------------------------------------! SUBROUTINE wtm_init_arrays IMPLICIT NONE REAL(wp) :: delta_r_factor !< REAL(wp) :: delta_r_init !< ! !-- To be able to allocate arrays with dimension of rotor rings and segments, !-- the maximum possible numbers of rings and segments have to be calculated: ALLOCATE( nrings(1:nturbines) ) ALLOCATE( delta_r(1:nturbines) ) nrings(:) = 0 delta_r(:) = 0.0_wp ! !-- Thickness (radial) of each ring and length (tangential) of each segment: delta_r_factor = segment_width delta_t_factor = segment_length delta_r_init = delta_r_factor * MIN( dx, dy, dz) delta_t = delta_t_factor * MIN( dx, dy, dz) DO inot = 1, nturbines ! !-- Determine number of rings: nrings(inot) = NINT( rr(inot) / delta_r_init ) delta_r(inot) = rr(inot) / nrings(inot) ENDDO nrings_max = MAXVAL(nrings) ALLOCATE( nsegs(1:nrings_max,1:nturbines) ) ALLOCATE( nsegs_total(1:nturbines) ) nsegs(:,:) = 0 nsegs_total(:) = 0 DO inot = 1, nturbines DO ring = 1, nrings(inot) ! !-- Determine number of segments for each ring: nsegs(ring,inot) = MAX( 8, CEILING( delta_r_factor * pi * & ( 2.0_wp * ring - 1.0_wp ) / & delta_t_factor ) ) ENDDO ! !-- Total sum of all rotor segments: nsegs_total(inot) = SUM( nsegs(:,inot) ) ENDDO ! !-- Maximum number of segments per ring: nsegs_max = MAXVAL(nsegs) !! !!-- TODO: Folgendes im Header ausgeben! ! IF ( myid == 0 ) THEN ! PRINT*, 'nrings(1) = ', nrings(1) ! PRINT*, '--------------------------------------------------' ! PRINT*, 'nsegs(:,1) = ', nsegs(:,1) ! PRINT*, '--------------------------------------------------' ! PRINT*, 'nrings_max = ', nrings_max ! PRINT*, 'nsegs_max = ', nsegs_max ! PRINT*, 'nsegs_total(1) = ', nsegs_total(1) ! ENDIF ! !-- Allocate 1D arrays (dimension = number of turbines) ALLOCATE( i_hub(1:nturbines) ) ALLOCATE( i_smear(1:nturbines) ) ALLOCATE( j_hub(1:nturbines) ) ALLOCATE( j_smear(1:nturbines) ) ALLOCATE( k_hub(1:nturbines) ) ALLOCATE( k_smear(1:nturbines) ) ALLOCATE( torque_total(1:nturbines) ) ALLOCATE( thrust_rotor(1:nturbines) ) ! !-- Allocation of the 1D arrays for speed pitch_control ALLOCATE( omega_gen(1:nturbines) ) ALLOCATE( omega_gen_old(1:nturbines) ) ALLOCATE( omega_gen_f(1:nturbines) ) ALLOCATE( omega_gen_f_old(1:nturbines) ) ALLOCATE( pitch_add_old(1:nturbines) ) ALLOCATE( torque_gen(1:nturbines) ) ALLOCATE( torque_gen_old(1:nturbines) ) ! !-- Allocation of the 1D arrays for yaw control ALLOCATE( yawdir(1:nturbines) ) ALLOCATE( u_inflow(1:nturbines) ) ALLOCATE( wdir(1:nturbines) ) ALLOCATE( u_inflow_l(1:nturbines) ) ALLOCATE( wdir_l(1:nturbines) ) ALLOCATE( phi_yaw_l(1:nturbines) ) ! !-- Allocate 1D arrays (dimension = number of rotor segments) ALLOCATE( alpha_attack(1:nsegs_max) ) ALLOCATE( chord(1:nsegs_max) ) ALLOCATE( phi_rel(1:nsegs_max) ) ALLOCATE( thrust_seg(1:nsegs_max) ) ALLOCATE( torque_seg_y(1:nsegs_max) ) ALLOCATE( torque_seg_z(1:nsegs_max) ) ALLOCATE( turb_cd(1:nsegs_max) ) ALLOCATE( turb_cl(1:nsegs_max) ) ALLOCATE( vrel(1:nsegs_max) ) ALLOCATE( vtheta(1:nsegs_max) ) ! !-- Allocate 2D arrays (dimension = number of rotor rings and segments) ALLOCATE( rbx(1:nrings_max,1:nsegs_max) ) ALLOCATE( rby(1:nrings_max,1:nsegs_max) ) ALLOCATE( rbz(1:nrings_max,1:nsegs_max) ) ALLOCATE( thrust_ring(1:nrings_max,1:nsegs_max) ) ALLOCATE( torque_ring_y(1:nrings_max,1:nsegs_max) ) ALLOCATE( torque_ring_z(1:nrings_max,1:nsegs_max) ) ! !-- Allocate additional 2D arrays ALLOCATE( rotx(1:nturbines,1:3) ) ALLOCATE( roty(1:nturbines,1:3) ) ALLOCATE( rotz(1:nturbines,1:3) ) ! !-- Allocate 3D arrays (dimension = number of grid points) ALLOCATE( nac_cd_surf(nzb:nzt+1,nysg:nyng,nxlg:nxrg) ) ALLOCATE( rot_tend_x(nzb:nzt+1,nysg:nyng,nxlg:nxrg) ) ALLOCATE( rot_tend_y(nzb:nzt+1,nysg:nyng,nxlg:nxrg) ) ALLOCATE( rot_tend_z(nzb:nzt+1,nysg:nyng,nxlg:nxrg) ) ALLOCATE( thrust(nzb:nzt+1,nysg:nyng,nxlg:nxrg) ) ALLOCATE( torque_y(nzb:nzt+1,nysg:nyng,nxlg:nxrg) ) ALLOCATE( torque_z(nzb:nzt+1,nysg:nyng,nxlg:nxrg) ) ALLOCATE( tow_cd_surf(nzb:nzt+1,nysg:nyng,nxlg:nxrg) ) ! !-- Allocate additional 3D arrays ALLOCATE( u_int(1:nturbines,1:nrings_max,1:nsegs_max) ) ALLOCATE( u_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) ) ALLOCATE( v_int(1:nturbines,1:nrings_max,1:nsegs_max) ) ALLOCATE( v_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) ) ALLOCATE( w_int(1:nturbines,1:nrings_max,1:nsegs_max) ) ALLOCATE( w_int_1_l(1:nturbines,1:nrings_max,1:nsegs_max) ) ! !-- All of the arrays are initialized with a value of zero: i_hub(:) = 0 i_smear(:) = 0 j_hub(:) = 0 j_smear(:) = 0 k_hub(:) = 0 k_smear(:) = 0 torque_total(:) = 0.0_wp thrust_rotor(:) = 0.0_wp omega_gen(:) = 0.0_wp omega_gen_old(:) = 0.0_wp omega_gen_f(:) = 0.0_wp omega_gen_f_old(:) = 0.0_wp pitch_add_old(:) = 0.0_wp torque_gen(:) = 0.0_wp torque_gen_old(:) = 0.0_wp yawdir(:) = 0.0_wp wdir(:) = 0.0_wp u_inflow(:) = 0.0_wp ! !-- Allocate 1D arrays (dimension = number of rotor segments) alpha_attack(:) = 0.0_wp chord(:) = 0.0_wp phi_rel(:) = 0.0_wp thrust_seg(:) = 0.0_wp torque_seg_y(:) = 0.0_wp torque_seg_z(:) = 0.0_wp turb_cd(:) = 0.0_wp turb_cl(:) = 0.0_wp vrel(:) = 0.0_wp vtheta(:) = 0.0_wp rbx(:,:) = 0.0_wp rby(:,:) = 0.0_wp rbz(:,:) = 0.0_wp thrust_ring(:,:) = 0.0_wp torque_ring_y(:,:) = 0.0_wp torque_ring_z(:,:) = 0.0_wp rotx(:,:) = 0.0_wp roty(:,:) = 0.0_wp rotz(:,:) = 0.0_wp turb_cl_tab(:,:) = 0.0_wp turb_cd_tab(:,:) = 0.0_wp nac_cd_surf(:,:,:) = 0.0_wp rot_tend_x(:,:,:) = 0.0_wp rot_tend_y(:,:,:) = 0.0_wp rot_tend_z(:,:,:) = 0.0_wp thrust(:,:,:) = 0.0_wp torque_y(:,:,:) = 0.0_wp torque_z(:,:,:) = 0.0_wp tow_cd_surf(:,:,:) = 0.0_wp u_int(:,:,:) = 0.0_wp u_int_1_l(:,:,:) = 0.0_wp v_int(:,:,:) = 0.0_wp v_int_1_l(:,:,:) = 0.0_wp w_int(:,:,:) = 0.0_wp w_int_1_l(:,:,:) = 0.0_wp END SUBROUTINE wtm_init_arrays !------------------------------------------------------------------------------! ! Description: ! ------------ !> Initialization of the wind turbine model !------------------------------------------------------------------------------! SUBROUTINE wtm_init IMPLICIT NONE INTEGER(iwp) :: i !< running index INTEGER(iwp) :: j !< running index INTEGER(iwp) :: k !< running index ! !-- Help variables for the smearing function REAL(wp) :: eps_kernel !< ! !-- Help variables for calculation of the tower drag INTEGER(iwp) :: tower_n !< INTEGER(iwp) :: tower_s !< ! !-- Help variables for the calulaction of the nacelle drag INTEGER(iwp) :: i_ip !< INTEGER(iwp) :: i_ipg !< REAL(wp) :: yvalue REAL(wp) :: dy_int !< REAL(wp) :: dz_int !< REAL(wp), DIMENSION(:,:), ALLOCATABLE :: circle_points !< INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nacb !< INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nacl !< INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nacr !< INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: index_nact !< ALLOCATE( index_nacb(1:nturbines) ) ALLOCATE( index_nacl(1:nturbines) ) ALLOCATE( index_nacr(1:nturbines) ) ALLOCATE( index_nact(1:nturbines) ) IF ( speed_control) THEN CALL wtm_speed_control ENDIF ! !------------------------------------------------------------------------------! !-- Calculation of parameters for the regularization kernel !-- (smearing of the forces) !------------------------------------------------------------------------------! ! !-- In the following, some of the required parameters for the smearing will !-- be calculated: !-- The kernel is set equal to twice the grid spacing which has turned out to !-- be a reasonable value (see e.g. Troldborg et al. (2013), Wind Energy, !-- DOI: 10.1002/we.1608): eps_kernel = 2.0_wp * dx ! !-- The zero point (eps_min) of the polynomial function must be the following !-- if the integral of the polynomial function (for values < eps_min) shall !-- be equal to the integral of the Gaussian function used before: eps_min = ( 105.0_wp / 32.0_wp )**( 1.0_wp / 3.0_wp ) * & pi**( 1.0_wp / 6.0_wp ) * eps_kernel ! !-- Square of eps_min: eps_min2 = eps_min**2 ! !-- Parameters in the polynomial function: pol_a = 1.0_wp / eps_min**4 pol_b = 2.0_wp / eps_min**2 ! !-- Normalization factor which is the inverse of the integral of the smearing !-- function: eps_factor = 105.0_wp / ( 32.0_wp * pi * eps_min**3 ) !-- Change tilt angle to rad: tilt = tilt * pi / 180.0_wp ! !-- Change yaw angle to rad: phi_yaw(:) = phi_yaw(:) * pi / 180.0_wp DO inot = 1, nturbines ! !-- Rotate the rotor coordinates in case yaw and tilt are defined CALL wtm_rotate_rotor( inot ) ! !-- Determine the indices of the hub height i_hub(inot) = INT( rcx(inot) / dx ) j_hub(inot) = INT( ( rcy(inot) + 0.5_wp * dy ) / dy ) k_hub(inot) = INT( ( rcz(inot) + 0.5_wp * dz ) / dz ) ! !-- Determining the area to which the smearing of the forces is applied. !-- As smearing now is effectively applied only for distances smaller than !-- eps_min, the smearing area can be further limited and regarded as a !-- function of eps_min: i_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dx ) j_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dy ) k_smear(inot) = CEILING( ( rr(inot) + eps_min ) / dz ) ENDDO ! !------------------------------------------------------------------------------! !-- Determine the area within each grid cell that overlaps with the area !-- of the nacelle and the tower (needed for calculation of the forces) !------------------------------------------------------------------------------! ! !-- Note: so far this is only a 2D version, in that the mean flow is !-- perpendicular to the rotor area. ! !-- Allocation of the array containing information on the intersection points !-- between rotor disk and the numerical grid: upper_end = ( ny + 1 ) * 10000 ALLOCATE( circle_points(1:2,1:upper_end) ) circle_points(:,:) = 0.0_wp DO inot = 1, nturbines ! loop over number of turbines ! !-- Determine the grid index (u-grid) that corresponds to the location of !-- the rotor center (reduces the amount of calculations in the case that !-- the mean flow is perpendicular to the rotor area): i = i_hub(inot) ! !-- Determine the left and the right edge of the nacelle (corresponding !-- grid point indices): index_nacl(inot) = INT( ( rcy(inot) - rnac(inot) + 0.5_wp * dy ) / dy ) index_nacr(inot) = INT( ( rcy(inot) + rnac(inot) + 0.5_wp * dy ) / dy ) ! !-- Determine the bottom and the top edge of the nacelle (corresponding !-- grid point indices).The grid point index has to be increased by 1, as !-- the first level for the u-component (index 0) is situated below the !-- surface. All points between z=0 and z=dz/s would already be contained !-- in grid box 1. index_nacb(inot) = INT( ( rcz(inot) - rnac(inot) ) / dz ) + 1 index_nact(inot) = INT( ( rcz(inot) + rnac(inot) ) / dz ) + 1 ! !-- Determine the indices of the grid boxes containing the left and !-- the right boundaries of the tower: tower_n = ( rcy(inot) + 0.5_wp * dtow(inot) - 0.5_wp * dy ) / dy tower_s = ( rcy(inot) - 0.5_wp * dtow(inot) - 0.5_wp * dy ) / dy ! !-- Determine the fraction of the grid box area overlapping with the tower !-- area and multiply it with the drag of the tower: IF ( ( nxlg <= i ) .AND. ( nxrg >= i ) ) THEN DO j = nys, nyn ! !-- Loop from south to north boundary of tower IF ( ( j >= tower_s ) .AND. ( j <= tower_n ) ) THEN DO k = nzb, nzt IF ( k == k_hub(inot) ) THEN IF ( tower_n - tower_s >= 1 ) THEN ! !-- leftmost and rightmost grid box: IF ( j == tower_s ) THEN tow_cd_surf(k,j,i) = ( rcz(inot) - & ( k_hub(inot) * dz - 0.5_wp * dz ) ) * & ! extension in z-direction ( ( tower_s + 1.0_wp + 0.5_wp ) * dy - & ( rcy(inot) - 0.5_wp * dtow(inot) ) ) * & ! extension in y-direction turb_cd_tower(inot) ELSEIF ( j == tower_n ) THEN tow_cd_surf(k,j,i) = ( rcz(inot) - & ( k_hub(inot) * dz - 0.5_wp * dz ) ) * & ! extension in z-direction ( ( rcy(inot) + 0.5_wp * dtow(inot) ) - & ( tower_n + 0.5_wp ) * dy ) * & ! extension in y-direction turb_cd_tower(inot) ! !-- grid boxes inbetween !-- (where tow_cd_surf = grid box area): ELSE tow_cd_surf(k,j,i) = ( rcz(inot) - & ( k_hub(inot) * dz - 0.5_wp * dz ) ) * & dy * turb_cd_tower(inot) ENDIF ! !-- tower lies completely within one grid box: ELSE tow_cd_surf(k,j,i) = ( rcz(inot) - & ( k_hub(inot) * dz - 0.5_wp * dz ) ) * & dtow(inot) * turb_cd_tower(inot) ENDIF ! !-- In case that k is smaller than k_hub the following actions !-- are carried out: ELSEIF ( k < k_hub(inot) ) THEN IF ( ( tower_n - tower_s ) >= 1 ) THEN ! !-- leftmost and rightmost grid box: IF ( j == tower_s ) THEN tow_cd_surf(k,j,i) = dz * ( & ( tower_s + 1 + 0.5_wp ) * dy - & ( rcy(inot) - 0.5_wp * dtow(inot) ) & ) * turb_cd_tower(inot) ELSEIF ( j == tower_n ) THEN tow_cd_surf(k,j,i) = dz * ( & ( rcy(inot) + 0.5_wp * dtow(inot) ) - & ( tower_n + 0.5_wp ) * dy & ) * turb_cd_tower(inot) ! !-- grid boxes inbetween !-- (where tow_cd_surf = grid box area): ELSE tow_cd_surf(k,j,i) = dz * dy * turb_cd_tower(inot) ENDIF ! !-- tower lies completely within one grid box: ELSE tow_cd_surf(k,j,i) = dz * dtow(inot) * & turb_cd_tower(inot) ENDIF ! end if larger than grid box ENDIF ! end if k == k_hub ENDDO ! end loop over k ENDIF ! end if inside north and south boundary of tower ENDDO ! end loop over j ENDIF ! end if hub inside domain + ghostpoints CALL exchange_horiz( tow_cd_surf, nbgp ) ! !-- Calculation of the nacelle area !-- CAUTION: Currently disabled due to segmentation faults on the FLOW HPC !-- cluster (Oldenburg) !! !!-- Tabulate the points on the circle that are required in the following for !!-- the calculation of the Riemann integral (node points; they are called !!-- circle_points in the following): ! ! dy_int = dy / 10000.0_wp ! ! DO i_ip = 1, upper_end ! yvalue = dy_int * ( i_ip - 0.5_wp ) + 0.5_wp * dy !<--- segmentation fault ! sqrt_arg = rnac(inot)**2 - ( yvalue - rcy(inot) )**2 !<--- segmentation fault ! IF ( sqrt_arg >= 0.0_wp ) THEN !! !!-- bottom intersection point ! circle_points(1,i_ip) = rcz(inot) - SQRT( sqrt_arg ) !! !!-- top intersection point ! circle_points(2,i_ip) = rcz(inot) + SQRT( sqrt_arg ) !<--- segmentation fault ! ELSE ! circle_points(:,i_ip) = -111111 !<--- segmentation fault ! ENDIF ! ENDDO ! ! ! DO j = nys, nyn !! !!-- In case that the grid box is located completely outside the nacelle !!-- (y) it can automatically be stated that there is no overlap between !!-- the grid box and the nacelle and consequently we can set !!-- nac_cd_surf(:,j,i) = 0.0: ! IF ( ( j >= index_nacl(inot) ) .AND. ( j <= index_nacr(inot) ) ) THEN ! DO k = nzb+1, nzt !! !!-- In case that the grid box is located completely outside the !!-- nacelle (z) it can automatically be stated that there is no !!-- overlap between the grid box and the nacelle and consequently !!-- we can set nac_cd_surf(k,j,i) = 0.0: ! IF ( ( k >= index_nacb(inot) ) .OR. & ! ( k <= index_nact(inot) ) ) THEN !! !!-- For all other cases Riemann integrals are calculated. !!-- Here, the points on the circle that have been determined !!-- above are used in order to calculate the overlap between the !!-- gridbox and the nacelle area (area approached by 10000 !!-- rectangulars dz_int * dy_int): ! DO i_ipg = 1, 10000 ! dz_int = dz ! i_ip = j * 10000 + i_ipg !! !!-- Determine the vertical extension dz_int of the circle !!-- within the current grid box: ! IF ( ( circle_points(2,i_ip) < zw(k) ) .AND. & !<--- segmentation fault ! ( circle_points(2,i_ip) >= zw(k-1) ) ) THEN ! dz_int = dz_int - & !<--- segmentation fault ! ( zw(k) - circle_points(2,i_ip) ) ! ENDIF ! IF ( ( circle_points(1,i_ip) <= zw(k) ) .AND. & !<--- segmentation fault ! ( circle_points(1,i_ip) > zw(k-1) ) ) THEN ! dz_int = dz_int - & ! ( circle_points(1,i_ip) - zw(k-1) ) ! ENDIF ! IF ( zw(k-1) > circle_points(2,i_ip) ) THEN ! dz_int = 0.0_wp ! ENDIF ! IF ( zw(k) < circle_points(1,i_ip) ) THEN ! dz_int = 0.0_wp ! ENDIF ! IF ( ( nxlg <= i ) .AND. ( nxrg >= i ) ) THEN ! nac_cd_surf(k,j,i) = nac_cd_surf(k,j,i) + & !<--- segmentation fault ! dy_int * dz_int * turb_cd_nacelle(inot) ! ENDIF ! ENDDO ! ENDIF ! ENDDO ! ENDIF ! ! ENDDO ! ! CALL exchange_horiz( nac_cd_surf, nbgp ) !<--- segmentation fault ENDDO ! end of loop over turbines tow_cd_surf = tow_cd_surf / ( dx * dy * dz ) ! Normalize tower drag nac_cd_surf = nac_cd_surf / ( dx * dy * dz ) ! Normalize nacelle drag CALL wtm_read_blade_tables END SUBROUTINE wtm_init !------------------------------------------------------------------------------! ! Description: ! ------------ !> Read in layout of the rotor blade , the lift and drag tables !> and the distribution of lift and drag tables along the blade !------------------------------------------------------------------------------! ! SUBROUTINE wtm_read_blade_tables IMPLICIT NONE INTEGER(iwp) :: ii !< running index INTEGER(iwp) :: jj !< running index INTEGER(iwp) :: ierrn !< CHARACTER(200) :: chmess !< Read in string INTEGER(iwp) :: dlen !< no. rows of local table INTEGER(iwp) :: dlenbl !< no. rows of cd, cl table INTEGER(iwp) :: ialpha !< table position of current alpha value INTEGER(iwp) :: iialpha !< INTEGER(iwp) :: iir !< INTEGER(iwp) :: radres !< radial resolution INTEGER(iwp) :: t1 !< no. of airfoil INTEGER(iwp) :: t2 !< no. of airfoil INTEGER(iwp) :: trow !< INTEGER(iwp) :: dlenbl_int !< no. rows of interpolated cd, cl tables REAL(wp) :: alpha_attack_i !< REAL(wp) :: weight_a !< REAL(wp) :: weight_b !< INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: ttoint1 !< INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: ttoint2 !< REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd_sel1 !< REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cd_sel2 !< REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl_sel1 !< REAL(wp), DIMENSION(:), ALLOCATABLE :: turb_cl_sel2 !< REAL(wp), DIMENSION(:), ALLOCATABLE :: read_cl_cd !< read in var array REAL(wp), DIMENSION(:), ALLOCATABLE :: alpha_attack_tab !< REAL(wp), DIMENSION(:), ALLOCATABLE :: trad1 !< REAL(wp), DIMENSION(:), ALLOCATABLE :: trad2 !< REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cd_table !< REAL(wp), DIMENSION(:,:), ALLOCATABLE :: turb_cl_table !< ALLOCATE ( read_cl_cd(1:2*nairfoils+1) ) ! !-- Read in the distribution of lift and drag tables along the blade, the !-- layout of the rotor blade and the lift and drag tables: OPEN ( 201, FILE='WTM_DATA', STATUS='OLD', FORM='FORMATTED', IOSTAT=ierrn ) IF ( ierrn /= 0 ) THEN message_string = 'file WTM_DATA does not exist' CALL message( 'wtm_init', 'PA0???', 1, 2, 0, 6, 0 ) ENDIF ! !-- Read distribution table: dlen = 0 READ ( 201, '(3/)' ) rloop3: DO READ ( 201, *, IOSTAT=ierrn ) chmess IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop3 dlen = dlen + 1 ENDDO rloop3 ALLOCATE( trad1(1:dlen), trad2(1:dlen), ttoint1(1:dlen), ttoint2(1:dlen)) DO jj = 1,dlen+1 BACKSPACE ( 201, IOSTAT=ierrn ) ENDDO DO jj = 1,dlen READ ( 201, * ) trad1(jj), trad2(jj), ttoint1(jj), ttoint2(jj) ENDDO ! !-- Read layout table: dlen = 0 READ ( 201, '(3/)') rloop1: DO READ ( 201, *, IOSTAT=ierrn ) chmess IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop1 dlen = dlen + 1 ENDDO rloop1 ALLOCATE( lrd(1:dlen), ard(1:dlen), crd(1:dlen) ) DO jj = 1, dlen+1 BACKSPACE ( 201, IOSTAT=ierrn ) ENDDO DO jj = 1, dlen READ ( 201, * ) lrd(jj), ard(jj), crd(jj) ENDDO ! !-- Read tables (turb_cl(alpha),turb_cd(alpha) for the different profiles: dlen = 0 READ ( 201, '(3/)' ) rloop2: DO READ ( 201, *, IOSTAT=ierrn ) chmess IF ( ierrn < 0 .OR. chmess == '#' .OR. chmess == '') EXIT rloop2 dlen = dlen + 1 ENDDO rloop2 ALLOCATE( alpha_attack_tab(1:dlen), turb_cl_table(1:dlen,1:nairfoils), & turb_cd_table(1:dlen,1:nairfoils) ) DO jj = 1,dlen+1 BACKSPACE ( 201, IOSTAT=ierrn ) ENDDO DO jj = 1,dlen READ ( 201, * ) read_cl_cd alpha_attack_tab(jj) = read_cl_cd(1) DO ii= 1, nairfoils turb_cl_table(jj,ii) = read_cl_cd(ii*2) turb_cd_table(jj,ii) = read_cl_cd(ii*2+1) ENDDO ENDDO dlenbl = dlen CLOSE ( 201 ) ! !-- For each possible radial position (resolution: 0.1 m --> 630 values) and !-- each possible angle of attack (resolution: 0.01 degrees --> 36000 values!) !-- determine the lift and drag coefficient by interpolating between the !-- tabulated values of each table (interpolate to current angle of attack) !-- and between the tables (interpolate to current radial position): ALLOCATE( turb_cl_sel1(0:dlenbl) ) ALLOCATE( turb_cl_sel2(0:dlenbl) ) ALLOCATE( turb_cd_sel1(0:dlenbl) ) ALLOCATE( turb_cd_sel2(0:dlenbl) ) radres = INT( rr(1) * 10.0_wp ) + 1_iwp dlenbl_int = INT( 360.0_wp / accu_cl_cd_tab ) + 1_iwp ALLOCATE( turb_cl_tab(0:dlenbl_int,1:radres) ) ALLOCATE( turb_cd_tab(0:dlenbl_int,1:radres) ) DO iir = 1, radres ! loop over radius DO iialpha = 1, dlenbl_int ! loop over angles cur_r = ( iir - 1_iwp ) * 0.1_wp alpha_attack_i = -180.0_wp + REAL( iialpha-1 ) * accu_cl_cd_tab ialpha = 1 DO WHILE ( ( alpha_attack_i > alpha_attack_tab(ialpha) ) .AND. (ialpha <= dlen ) ) ialpha = ialpha + 1 ENDDO ! !-- Find position in table lct = MINLOC( ABS( trad1 - cur_r ) ) ! lct(1) = lct(1) IF ( ( trad1(lct(1)) - cur_r ) .GT. 0.0 ) THEN lct(1) = lct(1) - 1 ENDIF trow = lct(1) ! !-- Calculate weights for interpolation weight_a = ( trad2(trow) - cur_r ) / ( trad2(trow) - trad1(trow) ) weight_b = ( cur_r - trad1(trow) ) / ( trad2(trow) - trad1(trow) ) t1 = ttoint1(trow) t2 = ttoint2(trow) IF ( t1 .EQ. t2 ) THEN ! if both are the same, the weights are NaN weight_a = 0.5_wp ! then do interpolate in between same twice weight_b = 0.5_wp ! using 0.5 as weight ENDIF IF ( t1 == 0 .AND. t2 == 0 ) THEN turb_cd_sel1 = 0.0_wp turb_cd_sel2 = 0.0_wp turb_cl_sel1 = 0.0_wp turb_cl_sel2 = 0.0_wp ELSE turb_cd_sel1 = turb_cd_table(:,t1) turb_cd_sel2 = turb_cd_table(:,t2) turb_cl_sel1 = turb_cl_table(:,t1) turb_cl_sel2 = turb_cl_table(:,t2) ENDIF ! !-- Interpolation of lift and drag coefficiencts on fine grid of radius !-- segments and angles of attack turb_cl_tab(iialpha,iir) = ( alpha_attack_tab(ialpha) - & alpha_attack_i ) / & ( alpha_attack_tab(ialpha) - & alpha_attack_tab(ialpha-1) ) * & ( weight_a * turb_cl_sel1(ialpha-1) + & weight_b * turb_cl_sel2(ialpha-1) ) +& ( alpha_attack_i - & alpha_attack_tab(ialpha-1) ) / & ( alpha_attack_tab(ialpha) - & alpha_attack_tab(ialpha-1) ) * & ( weight_a * turb_cl_sel1(ialpha) + & weight_b * turb_cl_sel2(ialpha) ) turb_cd_tab(iialpha,iir) = ( alpha_attack_tab(ialpha) - & alpha_attack_i ) / & ( alpha_attack_tab(ialpha) - & alpha_attack_tab(ialpha-1) ) * & ( weight_a * turb_cd_sel1(ialpha-1) + & weight_b * turb_cd_sel2(ialpha-1) ) +& ( alpha_attack_i - & alpha_attack_tab(ialpha-1) ) / & ( alpha_attack_tab(ialpha) - & alpha_attack_tab(ialpha-1) ) * & ( weight_a * turb_cd_sel1(ialpha) + & weight_b * turb_cd_sel2(ialpha) ) ENDDO ! end loop over angles of attack ENDDO ! end loop over radius END SUBROUTINE wtm_read_blade_tables !------------------------------------------------------------------------------! ! Description: ! ------------ !> The projection matrix for the coordinate system of therotor disc in respect !> to the yaw and tilt angle of the rotor is calculated !------------------------------------------------------------------------------! SUBROUTINE wtm_rotate_rotor( inot ) IMPLICIT NONE INTEGER(iwp) :: inot ! !-- Calculation of the rotation matrix for the application of the tilt to !-- the rotors rot_eigen_rad(1) = SIN( phi_yaw(inot) ) ! x-component of the radial eigenvector rot_eigen_rad(2) = COS( phi_yaw(inot) ) ! y-component of the radial eigenvector rot_eigen_rad(3) = 0.0_wp ! z-component of the radial eigenvector rot_eigen_azi(1) = 0.0_wp ! x-component of the azimuth eigenvector rot_eigen_azi(2) = 0.0_wp ! y-component of the azimuth eigenvector rot_eigen_azi(3) = 1.0_wp ! z-component of the azimuth eigenvector rot_eigen_nor(1) = COS( phi_yaw(inot) ) ! x-component of the normal eigenvector rot_eigen_nor(2) = -SIN( phi_yaw(inot) ) ! y-component of the normal eigenvector rot_eigen_nor(3) = 0.0_wp ! z-component of the normal eigenvector ! !-- Calculation of the coordinate transformation matrix to apply a tilt to !-- the rotor. If tilt = 0, rot_coord_trans is a unit matrix. rot_coord_trans(inot,1,1) = rot_eigen_rad(1)**2 * & ( 1.0_wp - COS( tilt ) ) + COS( tilt ) rot_coord_trans(inot,1,2) = rot_eigen_rad(1) * rot_eigen_rad(2) * & ( 1.0_wp - COS( tilt ) ) - & rot_eigen_rad(3) * SIN( tilt ) rot_coord_trans(inot,1,3) = rot_eigen_rad(1) * rot_eigen_rad(3) * & ( 1.0_wp - COS( tilt ) ) + & rot_eigen_rad(2) * SIN( tilt ) rot_coord_trans(inot,2,1) = rot_eigen_rad(2) * rot_eigen_rad(1) * & ( 1.0_wp - COS( tilt ) ) + & rot_eigen_rad(3) * SIN( tilt ) rot_coord_trans(inot,2,2) = rot_eigen_rad(2)**2 * & ( 1.0_wp - COS( tilt ) ) + COS( tilt ) rot_coord_trans(inot,2,3) = rot_eigen_rad(2) * rot_eigen_rad(3) * & ( 1.0_wp - COS( tilt ) ) - & rot_eigen_rad(1) * SIN( tilt ) rot_coord_trans(inot,3,1) = rot_eigen_rad(3) * rot_eigen_rad(1) * & ( 1.0_wp - COS( tilt ) ) - & rot_eigen_rad(2) * SIN( tilt ) rot_coord_trans(inot,3,2) = rot_eigen_rad(3) * rot_eigen_rad(2) * & ( 1.0_wp - COS( tilt ) ) + & rot_eigen_rad(1) * SIN( tilt ) rot_coord_trans(inot,3,3) = rot_eigen_rad(3)**2 * & ( 1.0_wp - COS( tilt ) ) + COS( tilt ) ! !-- Vectors for the Transformation of forces from the rotor's spheric !-- coordinate system to the cartesian coordinate system rotx(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_nor ) roty(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_rad ) rotz(inot,:) = MATMUL( rot_coord_trans(inot,:,:), rot_eigen_azi ) END SUBROUTINE wtm_rotate_rotor !------------------------------------------------------------------------------! ! Description: ! ------------ !> Calculation of the forces generated by the wind turbine !------------------------------------------------------------------------------! SUBROUTINE wtm_forces IMPLICIT NONE CHARACTER (LEN=2) :: turbine_id INTEGER(iwp) :: i, j, k !< loop indices INTEGER(iwp) :: inot !< turbine loop index (turbine id) INTEGER(iwp) :: iialpha, iir !< INTEGER(iwp) :: rseg, rseg_int !< INTEGER(iwp) :: ring, ring_int !< INTEGER(iwp) :: ii, jj, kk !< REAL(wp) :: sin_rot, cos_rot !< REAL(wp) :: sin_yaw, cos_yaw !< REAL(wp) :: aa, bb, cc, dd !< interpolation distances REAL(wp) :: gg !< interpolation volume var REAL(wp) :: dist_u_3d, dist_v_3d, dist_w_3d !< smearing distances ! ! Variables for pitch control REAL(wp) :: torque_max=0.0_wp LOGICAL :: pitch_sw=.FALSE. INTEGER(iwp), DIMENSION(1) :: lct=0 REAL(wp), DIMENSION(1) :: rad_d=0.0_wp REAL(wp) :: tl_factor !< factor for tip loss correction CALL cpu_log( log_point_s(61), 'wtm_forces', 'start' ) IF ( simulated_time >= time_turbine_on ) THEN ! !-- Set forces to zero for each new time step: thrust(:,:,:) = 0.0_wp torque_y(:,:,:) = 0.0_wp torque_z(:,:,:) = 0.0_wp torque_total(:) = 0.0_wp rot_tend_x(:,:,:) = 0.0_wp rot_tend_y(:,:,:) = 0.0_wp rot_tend_z(:,:,:) = 0.0_wp thrust_rotor(:) = 0.0_wp ! !-- Loop over number of turbines: DO inot = 1, nturbines cos_yaw = COS(phi_yaw(inot)) sin_yaw = SIN(phi_yaw(inot)) ! !-- Loop over rings of each turbine: DO ring = 1, nrings(inot) thrust_seg(:) = 0.0_wp torque_seg_y(:) = 0.0_wp torque_seg_z(:) = 0.0_wp ! !-- Determine distance between each ring (center) and the hub: cur_r = (ring - 0.5_wp) * delta_r(inot) ! !-- Loop over segments of each ring of each turbine: DO rseg = 1, nsegs(ring,inot) ! !-- !-----------------------------------------------------------! !-- !-- Determine coordinates of the ring segments --! !-- !-----------------------------------------------------------! ! !-- Determine angle of ring segment towards zero degree angle of !-- rotor system (at zero degree rotor direction vectors aligned !-- with y-axis): phi_rotor = rseg * 2.0_wp * pi / nsegs(ring,inot) cos_rot = COS( phi_rotor ) sin_rot = SIN( phi_rotor ) !-- Now the direction vectors can be determined with respect to !-- the yaw and tilt angle: re(1) = cos_rot * sin_yaw re(2) = cos_rot * cos_yaw re(3) = sin_rot rote = MATMUL( rot_coord_trans(inot,:,:), re ) ! !-- Coordinates of the single segments (center points): rbx(ring,rseg) = rcx(inot) + cur_r * rote(1) rby(ring,rseg) = rcy(inot) + cur_r * rote(2) rbz(ring,rseg) = rcz(inot) + cur_r * rote(3) !-- !-----------------------------------------------------------! !-- !-- Interpolation of the velocity components from the --! !-- !-- cartesian grid point to the coordinates of each ring --! !-- !-- segment (follows a method used in the particle model) --! !-- !-----------------------------------------------------------! u_int(inot,ring,rseg) = 0.0_wp u_int_1_l(inot,ring,rseg) = 0.0_wp v_int(inot,ring,rseg) = 0.0_wp v_int_1_l(inot,ring,rseg) = 0.0_wp w_int(inot,ring,rseg) = 0.0_wp w_int_1_l(inot,ring,rseg) = 0.0_wp ! !-- Interpolation of the u-component: ii = rbx(ring,rseg) * ddx jj = ( rby(ring,rseg) - 0.5_wp * dy ) * ddy kk = ( rbz(ring,rseg) - 0.5_wp * dz ) / dz ! !-- Interpolate only if all required information is available on !-- the current PE: IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN aa = ( ( ii + 1 ) * dx - rbx(ring,rseg) ) * & ( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) ) bb = ( rbx(ring,rseg) - ii * dx ) * & ( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) ) cc = ( ( ii+1 ) * dx - rbx(ring,rseg) ) * & ( rby(ring,rseg) - ( jj + 0.5_wp ) * dy ) dd = ( rbx(ring,rseg) - ii * dx ) * & ( rby(ring,rseg) - ( jj + 0.5_wp ) * dy ) gg = dx * dy u_int_l = ( aa * u(kk,jj,ii) + & bb * u(kk,jj,ii+1) + & cc * u(kk,jj+1,ii) + & dd * u(kk,jj+1,ii+1) & ) / gg u_int_u = ( aa * u(kk+1,jj,ii) + & bb * u(kk+1,jj,ii+1) + & cc * u(kk+1,jj+1,ii) + & dd * u(kk+1,jj+1,ii+1) & ) / gg u_int_1_l(inot,ring,rseg) = u_int_l + & ( rbz(ring,rseg) - zu(kk) ) / dz * & ( u_int_u - u_int_l ) ELSE u_int_1_l(inot,ring,rseg) = 0.0_wp ENDIF ELSE u_int_1_l(inot,ring,rseg) = 0.0_wp ENDIF ! !-- Interpolation of the v-component: ii = ( rbx(ring,rseg) - 0.5_wp * dx ) * ddx jj = rby(ring,rseg) * ddy kk = ( rbz(ring,rseg) + 0.5_wp * dz ) / dz ! !-- Interpolate only if all required information is available on !-- the current PE: IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN aa = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * & ( ( jj + 1 ) * dy - rby(ring,rseg) ) bb = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * & ( ( jj + 1 ) * dy - rby(ring,rseg) ) cc = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * & ( rby(ring,rseg) - jj * dy ) dd = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * & ( rby(ring,rseg) - jj * dy ) gg = dx * dy v_int_l = ( aa * v(kk,jj,ii) + & bb * v(kk,jj,ii+1) + & cc * v(kk,jj+1,ii) + & dd * v(kk,jj+1,ii+1) & ) / gg v_int_u = ( aa * v(kk+1,jj,ii) + & bb * v(kk+1,jj,ii+1) + & cc * v(kk+1,jj+1,ii) + & dd * v(kk+1,jj+1,ii+1) & ) / gg v_int_1_l(inot,ring,rseg) = v_int_l + & ( rbz(ring,rseg) - zu(kk) ) / dz * & ( v_int_u - v_int_l ) ELSE v_int_1_l(inot,ring,rseg) = 0.0_wp ENDIF ELSE v_int_1_l(inot,ring,rseg) = 0.0_wp ENDIF ! !-- Interpolation of the w-component: ii = ( rbx(ring,rseg) - 0.5_wp * dx ) * ddx jj = ( rby(ring,rseg) - 0.5_wp * dy ) * ddy kk = rbz(ring,rseg) / dz ! !-- Interpolate only if all required information is available on !-- the current PE: IF ( ( ii >= nxl ) .AND. ( ii <= nxr ) ) THEN IF ( ( jj >= nys ) .AND. ( jj <= nyn ) ) THEN aa = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * & ( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) ) bb = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * & ( ( jj + 1 + 0.5_wp ) * dy - rby(ring,rseg) ) cc = ( ( ii + 1 + 0.5_wp ) * dx - rbx(ring,rseg) ) * & ( rby(ring,rseg) - ( jj + 0.5_wp ) * dy ) dd = ( rbx(ring,rseg) - ( ii + 0.5_wp ) * dx ) * & ( rby(ring,rseg) - ( jj + 0.5_wp ) * dy ) gg = dx * dy w_int_l = ( aa * w(kk,jj,ii) + & bb * w(kk,jj,ii+1) + & cc * w(kk,jj+1,ii) + & dd * w(kk,jj+1,ii+1) & ) / gg w_int_u = ( aa * w(kk+1,jj,ii) + & bb * w(kk+1,jj,ii+1) + & cc * w(kk+1,jj+1,ii) + & dd * w(kk+1,jj+1,ii+1) & ) / gg w_int_1_l(inot,ring,rseg) = w_int_l + & ( rbz(ring,rseg) - zw(kk) ) / dz * & ( w_int_u - w_int_l ) ELSE w_int_1_l(inot,ring,rseg) = 0.0_wp ENDIF ELSE w_int_1_l(inot,ring,rseg) = 0.0_wp ENDIF ENDDO ENDDO ENDDO ! !-- Exchange between PEs (information required on each PE): #if defined( __parallel ) CALL MPI_ALLREDUCE( u_int_1_l, u_int, nturbines * MAXVAL(nrings) * & MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr ) CALL MPI_ALLREDUCE( v_int_1_l, v_int, nturbines * MAXVAL(nrings) * & MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr ) CALL MPI_ALLREDUCE( w_int_1_l, w_int, nturbines * MAXVAL(nrings) * & MAXVAL(nsegs), MPI_REAL, MPI_SUM, comm2d, ierr ) #else u_int = u_int_1_l v_int = v_int_1_l w_int = w_int_1_l #endif ! !-- Loop over number of turbines: DO inot = 1, nturbines pit_loop: DO IF ( pitch_sw ) THEN torque_total(inot) = 0.0_wp thrust_rotor(inot) = 0.0_wp pitch_add(inot) = pitch_add(inot) + 0.25_wp ! IF ( myid == 0 ) PRINT*, 'Pitch', inot, pitch_add(inot) ELSE cos_yaw = COS(phi_yaw(inot)) sin_yaw = SIN(phi_yaw(inot)) IF ( pitch_control ) THEN pitch_add(inot) = MAX(pitch_add_old(inot) - pitch_rate * & dt_3d , 0.0_wp ) ENDIF ENDIF ! !-- Loop over rings of each turbine: DO ring = 1, nrings(inot) ! !-- Determine distance between each ring (center) and the hub: cur_r = (ring - 0.5_wp) * delta_r(inot) ! !-- Loop over segments of each ring of each turbine: DO rseg = 1, nsegs(ring,inot) ! !-- Determine angle of ring segment towards zero degree angle of !-- rotor system (at zero degree rotor direction vectors aligned !-- with y-axis): phi_rotor = rseg * 2.0_wp * pi / nsegs(ring,inot) cos_rot = COS(phi_rotor) sin_rot = SIN(phi_rotor) ! !-- Now the direction vectors can be determined with respect to !-- the yaw and tilt angle: re(1) = cos_rot * sin_yaw re(2) = cos_rot * cos_yaw re(3) = sin_rot ! The current unit vector in azimuthal direction: rea(1) = - sin_rot * sin_yaw rea(2) = - sin_rot * cos_yaw rea(3) = cos_rot ! !-- To respect the yawing angle for the calculations of !-- velocities and forces the unit vectors perpendicular to the !-- rotor area in direction of the positive yaw angle are defined: ren(1) = cos_yaw ren(2) = - sin_yaw ren(3) = 0.0_wp ! !-- Multiplication with the coordinate transformation matrix !-- gives the final unit vector with consideration of the rotor !-- tilt: rote = MATMUL( rot_coord_trans(inot,:,:), re ) rota = MATMUL( rot_coord_trans(inot,:,:), rea ) rotn = MATMUL( rot_coord_trans(inot,:,:), ren ) ! !-- Coordinates of the single segments (center points): rbx(ring,rseg) = rcx(inot) + cur_r * rote(1) rby(ring,rseg) = rcy(inot) + cur_r * rote(2) rbz(ring,rseg) = rcz(inot) + cur_r * rote(3) ! !-- !-----------------------------------------------------------! !-- !-- Calculation of various angles and relative velocities --! !-- !-----------------------------------------------------------! ! !-- In the following the 3D-velocity field is projected its !-- components perpedicular and parallel to the rotor area !-- The calculation of forces will be done in the rotor- !-- coordinates y' and z. !-- The yaw angle will be reintroduced when the force is applied !-- on the hydrodynamic equations ! !-- Projection of the xy-velocities relative to the rotor area ! !-- Velocity perpendicular to the rotor area: u_rot = u_int(inot,ring,rseg)*rotn(1) + & v_int(inot,ring,rseg)*rotn(2) + & w_int(inot,ring,rseg)*rotn(3) ! !-- Projection of the 3D-velocity vector in the azimuthal !-- direction: vtheta(rseg) = rota(1) * u_int(inot,ring,rseg) + & rota(2) * v_int(inot,ring,rseg) + & rota(3) * w_int(inot,ring,rseg) ! !-- Determination of the angle phi_rel between the rotor plane !-- and the direction of the flow relative to the rotor: phi_rel(rseg) = ATAN( u_rot / & ( omega_rot(inot) * cur_r - & vtheta(rseg) ) ) ! !-- Interpolation of the local pitch angle from tabulated values !-- to the current radial position: lct=minloc(ABS(cur_r-lrd)) rad_d=cur_r-lrd(lct) IF (cur_r == 0.0_wp) THEN alpha_attack(rseg) = 0.0_wp ELSE IF (cur_r >= lrd(size(ard))) THEN alpha_attack(rseg) = ( ard(size(ard)) + & ard(size(ard)-1) ) / 2.0_wp ELSE alpha_attack(rseg) = ( ard(lct(1)) * & ( ( lrd(lct(1)+1) - cur_r ) / & ( lrd(lct(1)+1) - lrd(lct(1)) ) & ) ) + ( ard(lct(1)+1) * & ( ( cur_r - lrd(lct(1)) ) / & ( lrd(lct(1)+1) - lrd(lct(1)) ) ) ) ENDIF ! !-- In Fortran radian instead of degree is used as unit for all !-- angles. Therefore, a transformation from angles given in !-- degree to angles given in radian is necessary here: alpha_attack(rseg) = alpha_attack(rseg) * & ( (2.0_wp*pi) / 360.0_wp ) ! !-- Substraction of the local pitch angle to obtain the local !-- angle of attack: alpha_attack(rseg) = phi_rel(rseg) - alpha_attack(rseg) ! !-- Preliminary transformation back from angles given in radian !-- to angles given in degree: alpha_attack(rseg) = alpha_attack(rseg) * & ( 360.0_wp / (2.0_wp*pi) ) ! !-- Correct with collective pitch angle: alpha_attack = alpha_attack - pitch_add(inot) ! !-- Determination of the magnitude of the flow velocity relative !-- to the rotor: vrel(rseg) = SQRT( u_rot**2 + & ( omega_rot(inot) * cur_r - & vtheta(rseg) )**2 ) ! !-- !-----------------------------------------------------------! !-- !-- Interpolation of chord as well as lift and drag --! !-- !-- coefficients from tabulated values --! !-- !-----------------------------------------------------------! ! !-- Interpolation of the chord_length from tabulated values to !-- the current radial position: IF (cur_r == 0.0_wp) THEN chord(rseg) = 0.0_wp ELSE IF (cur_r >= lrd(size(crd))) THEN chord(rseg) = (crd(size(crd)) + ard(size(crd)-1)) / 2.0_wp ELSE chord(rseg) = ( crd(lct(1)) * & ( ( lrd(lct(1)+1) - cur_r ) / & ( lrd(lct(1)+1) - lrd(lct(1)) ) ) ) + & ( crd(lct(1)+1) * & ( ( cur_r-lrd(lct(1)) ) / & ( lrd(lct(1)+1) - lrd(lct(1)) ) ) ) ENDIF ! !-- Determine index of current angle of attack, needed for !-- finding the appropriate interpolated values of the lift and !-- drag coefficients (-180.0 degrees = 0, +180.0 degrees = 36000, !-- so one index every 0.01 degrees): iialpha = CEILING( ( alpha_attack(rseg) + 180.0_wp ) & * ( 1.0_wp / accu_cl_cd_tab ) ) ! !-- Determine index of current radial position, needed for !-- finding the appropriate interpolated values of the lift and !-- drag coefficients (one index every 0.1 m): iir = CEILING( cur_r * 10.0_wp ) ! !-- Read in interpolated values of the lift and drag coefficients !-- for the current radial position and angle of attack: turb_cl(rseg) = turb_cl_tab(iialpha,iir) turb_cd(rseg) = turb_cd_tab(iialpha,iir) ! !-- Final transformation back from angles given in degree to !-- angles given in radian: alpha_attack(rseg) = alpha_attack(rseg) * & ( (2.0_wp*pi) / 360.0_wp ) IF ( tl_cor ) THEN !-- Tip loss correction following Schito !-- Schito applies the tip loss correction only to the lift force !-- Therefore, the tip loss correction is only applied to the lift !-- coefficient and not to the drag coefficient in our case !-- tl_factor = ( 2.0 / pi ) * & ACOS( EXP( -1.0 * ( 3.0 * ( rr(inot) - cur_r ) / & ( 2.0 * cur_r * abs( sin( phi_rel(rseg) ) ) ) ) ) ) turb_cl(rseg) = tl_factor * turb_cl(rseg) END IF ! !-- !-----------------------------------------------------! !-- !-- Calculation of the forces --! !-- !-----------------------------------------------------! ! !-- Calculate the pre_factor for the thrust and torque forces: pre_factor = 0.5_wp * (vrel(rseg)**2) * 3.0_wp * & chord(rseg) * delta_r(inot) / nsegs(ring,inot) ! !-- Calculate the thrust force (x-component of the total force) !-- for each ring segment: thrust_seg(rseg) = pre_factor * & ( turb_cl(rseg) * COS(phi_rel(rseg)) + & turb_cd(rseg) * SIN(phi_rel(rseg)) ) ! !-- Determination of the second of the additional forces acting !-- on the flow in the azimuthal direction: force vector as basis !-- for torque (torque itself would be the vector product of the !-- radius vector and the force vector): torque_seg = pre_factor * & ( turb_cl(rseg) * SIN(phi_rel(rseg)) - & turb_cd(rseg) * COS(phi_rel(rseg)) ) ! !-- Decomposition of the force vector into two parts: !-- One acting along the y-direction and one acting along the !-- z-direction of the rotor coordinate system: torque_seg_y(rseg) = -torque_seg * sin_rot torque_seg_z(rseg) = torque_seg * cos_rot ! !-- Add the segment thrust to the thrust of the whole rotor thrust_rotor(inot) = thrust_rotor(inot) + & thrust_seg(rseg) torque_total(inot) = torque_total(inot) + (torque_seg * cur_r) ENDDO !-- end of loop over ring segments ! !-- Restore the forces into arrays containing all the segments of !-- each ring: thrust_ring(ring,:) = thrust_seg(:) torque_ring_y(ring,:) = torque_seg_y(:) torque_ring_z(ring,:) = torque_seg_z(:) ENDDO !-- end of loop over rings CALL cpu_log( log_point_s(62), 'wtm_controller', 'start' ) IF ( speed_control ) THEN ! !-- Calculation of the current generator speed for rotor speed control ! !-- The acceleration of the rotor speed is calculated from !-- the force balance of the accelerating torque !-- and the torque of the rotating rotor and generator om_rate = ( torque_total(inot) * air_dens * gear_eff - & gear_ratio * torque_gen_old(inot) ) / & ( inertia_rot + & gear_ratio * gear_ratio * inertia_gen ) * dt_3d ! !-- The generator speed is given by the product of gear gear_ratio !-- and rotor speed omega_gen(inot) = gear_ratio * ( omega_rot(inot) + om_rate ) ENDIF IF ( pitch_control ) THEN ! !-- If the current generator speed is above rated, the pitch is not !-- saturated and the change from the last time step is within the !-- maximum pitch rate, then the pitch loop is repeated with a pitch !-- gain IF ( ( omega_gen(inot) > rated_genspeed ) .AND. & ( pitch_add(inot) < 25.0_wp ) .AND. & ( pitch_add(inot) < pitch_add_old(inot) + & pitch_rate * dt_3d ) ) THEN pitch_sw = .TRUE. ! !-- Go back to beginning of pit_loop CYCLE pit_loop ENDIF ! !-- The current pitch is saved for the next time step pitch_add_old(inot) = pitch_add(inot) pitch_sw = .FALSE. ENDIF EXIT pit_loop ENDDO pit_loop ! Recursive pitch control loop ! !-- Call the rotor speed controller IF ( speed_control ) THEN ! !-- Find processor at i_hub, j_hub IF ( ( nxl <= i_hub(inot) ) .AND. ( nxr >= i_hub(inot) ) ) & THEN IF ( ( nys <= j_hub(inot) ) .AND. ( nyn >= j_hub(inot) ) )& THEN CALL wtm_speed_control( inot ) ENDIF ENDIF ENDIF CALL cpu_log( log_point_s(62), 'wtm_controller', 'stop' ) CALL cpu_log( log_point_s(63), 'wtm_smearing', 'start' ) !-- !-----------------------------------------------------------------! !-- !-- Regularization kernel --! !-- !-- Smearing of the forces and interpolation to cartesian grid --! !-- !-----------------------------------------------------------------! ! !-- The aerodynamic blade forces need to be distributed smoothly on !-- several mesh points in order to avoid singular behaviour ! !-- Summation over sum of weighted forces. The weighting factor !-- (calculated in user_init) includes information on the distance !-- between the center of the grid cell and the rotor segment under !-- consideration ! !-- To save computing time, apply smearing only for the relevant part !-- of the model domain: ! !-- !-- Calculation of the boundaries: i_smear(inot) = CEILING( ( rr(inot) * ABS( roty(inot,1) ) + & eps_min ) / dx ) j_smear(inot) = CEILING( ( rr(inot) * ABS( roty(inot,2) ) + & eps_min ) / dy ) DO i = MAX( nxl, i_hub(inot) - i_smear(inot) ), & MIN( nxr, i_hub(inot) + i_smear(inot) ) DO j = MAX( nys, j_hub(inot) - j_smear(inot) ), & MIN( nyn, j_hub(inot) + j_smear(inot) ) DO k = MAX( nzb_u_inner(j,i)+1, k_hub(inot) - k_smear(inot) ), & k_hub(inot) + k_smear(inot) DO ring = 1, nrings(inot) DO rseg = 1, nsegs(ring,inot) ! !-- Determine the square of the distance between the !-- current grid point and each rotor area segment: dist_u_3d = ( i * dx - rbx(ring,rseg) )**2 + & ( j * dy + 0.5_wp * dy - rby(ring,rseg) )**2 + & ( k * dz - 0.5_wp * dz - rbz(ring,rseg) )**2 dist_v_3d = ( i * dx + 0.5_wp * dx - rbx(ring,rseg) )**2 + & ( j * dy - rby(ring,rseg) )**2 + & ( k * dz - 0.5_wp * dz - rbz(ring,rseg) )**2 dist_w_3d = ( i * dx + 0.5_wp * dx - rbx(ring,rseg) )**2 + & ( j * dy + 0.5_wp * dy - rby(ring,rseg) )**2 + & ( k * dz - rbz(ring,rseg) )**2 ! !-- 3D-smearing of the forces with a polynomial function !-- (much faster than the old Gaussian function), using !-- some parameters that have been calculated in user_init. !-- The function is only similar to Gaussian function for !-- squared distances <= eps_min2: IF ( dist_u_3d <= eps_min2 ) THEN thrust(k,j,i) = thrust(k,j,i) + & thrust_ring(ring,rseg) * & ( ( pol_a * dist_u_3d - pol_b ) * & dist_u_3d + 1.0_wp ) * eps_factor ENDIF IF ( dist_v_3d <= eps_min2 ) THEN torque_y(k,j,i) = torque_y(k,j,i) + & torque_ring_y(ring,rseg) * & ( ( pol_a * dist_v_3d - pol_b ) *& dist_v_3d + 1.0_wp ) * eps_factor ENDIF IF ( dist_w_3d <= eps_min2 ) THEN torque_z(k,j,i) = torque_z(k,j,i) + & torque_ring_z(ring,rseg) * & ( ( pol_a * dist_w_3d - pol_b ) *& dist_w_3d + 1.0_wp ) * eps_factor ENDIF ENDDO ! End of loop over rseg ENDDO ! End of loop over ring ! !-- Rotation of force components: rot_tend_x(k,j,i) = rot_tend_x(k,j,i) + & thrust(k,j,i)*rotx(inot,1) + & torque_y(k,j,i)*roty(inot,1) + & torque_z(k,j,i)*rotz(inot,1) rot_tend_y(k,j,i) = rot_tend_y(k,j,i) + & thrust(k,j,i)*rotx(inot,2) + & torque_y(k,j,i)*roty(inot,2) + & torque_z(k,j,i)*rotz(inot,2) rot_tend_z(k,j,i) = rot_tend_z(k,j,i) + & thrust(k,j,i)*rotx(inot,3) + & torque_y(k,j,i)*roty(inot,3) + & torque_z(k,j,i)*rotz(inot,3) ENDDO ! End of loop over k ENDDO ! End of loop over j ENDDO ! End of loop over i CALL cpu_log( log_point_s(63), 'wtm_smearing', 'stop' ) ENDDO !-- end of loop over turbines IF ( yaw_control ) THEN ! !-- Allocate arrays for yaw control at first call !-- Can't be allocated before dt_3d is set IF ( start_up ) THEN WDLON = NINT( 30.0_wp / dt_3d ) ! 30s running mean array ALLOCATE( wd30(1:nturbines,1:WDLON) ) wd30 = 999.0_wp ! Set to dummy value ALLOCATE( wd30_l(1:WDLON) ) WDSHO = NINT( 2.0_wp / dt_3d ) ! 2s running mean array ALLOCATE( wd2(1:nturbines,1:WDSHO) ) wd2 = 999.0_wp ! Set to dummy value ALLOCATE( wd2_l(1:WDSHO) ) start_up = .FALSE. ENDIF ! !-- Calculate the inflow wind speed !-- !-- Loop over number of turbines: DO inot = 1, nturbines ! !-- Find processor at i_hub, j_hub IF ( ( nxl <= i_hub(inot) ) .AND. ( nxr >= i_hub(inot) ) ) & THEN IF ( ( nys <= j_hub(inot) ) .AND. ( nyn >= j_hub(inot) ) )& THEN u_inflow_l(inot) = u(k_hub(inot),j_hub(inot),i_hub(inot)) wdir_l(inot) = -1.0_wp * ATAN2( & 0.5_wp * ( v(k_hub(inot),j_hub(inot),i_hub(inot)+1) + & v(k_hub(inot),j_hub(inot),i_hub(inot)) ) , & 0.5_wp * ( u(k_hub(inot),j_hub(inot)+1,i_hub(inot)) + & u(k_hub(inot),j_hub(inot),i_hub(inot)) ) ) CALL wtm_yawcontrol( inot ) phi_yaw_l(inot) = phi_yaw(inot) ENDIF ENDIF ENDDO !-- end of loop over turbines ! !-- Transfer of information to the other cpus #if defined( __parallel ) CALL MPI_ALLREDUCE( u_inflow_l, u_inflow, nturbines, MPI_REAL, & MPI_SUM, comm2d, ierr ) CALL MPI_ALLREDUCE( wdir_l, wdir, nturbines, MPI_REAL, MPI_SUM, & comm2d, ierr ) CALL MPI_ALLREDUCE( phi_yaw_l, phi_yaw, nturbines, MPI_REAL, & MPI_SUM, comm2d, ierr ) #else u_inflow = u_inflow_l wdir = wdir_l phi_yaw = phi_yaw_l #endif DO inot = 1, nturbines ! !-- Update rotor orientation CALL wtm_rotate_rotor( inot ) ENDDO ! End of loop over turbines END IF ! end of yaw control IF ( speed_control ) THEN ! !-- Transfer of information to the other cpus ! CALL MPI_ALLREDUCE( omega_gen, omega_gen_old, nturbines, & ! MPI_REAL,MPI_SUM, comm2d, ierr ) #if defined( __parallel ) CALL MPI_ALLREDUCE( torque_gen, torque_gen_old, nturbines, & MPI_REAL, MPI_SUM, comm2d, ierr ) CALL MPI_ALLREDUCE( omega_rot_l, omega_rot, nturbines, & MPI_REAL, MPI_SUM, comm2d, ierr ) CALL MPI_ALLREDUCE( omega_gen_f, omega_gen_f_old, nturbines, & MPI_REAL, MPI_SUM, comm2d, ierr ) #else torque_gen_old = torque_gen omega_rot = omega_rot_l omega_gen_f_old = omega_gen_f #endif ENDIF DO inot = 1, nturbines IF ( myid == 0 ) THEN IF ( openfile_turb_mod(400+inot)%opened ) THEN WRITE ( 400+inot, 106 ) simulated_time, omega_rot(inot), & omega_gen(inot), torque_gen_old(inot), & torque_total(inot), pitch_add(inot), & torque_gen_old(inot)*omega_gen(inot)*gen_eff, & torque_total(inot)*omega_rot(inot)*air_dens, & thrust_rotor(inot), & wdir(inot)*180.0_wp/pi, & (phi_yaw(inot))*180.0_wp/pi ELSE WRITE ( turbine_id,'(I2.2)') inot OPEN ( 400+inot, FILE=( 'TURBINE_PARAMETERS'//turbine_id ), & FORM='FORMATTED' ) WRITE ( 400+inot, 105 ) inot WRITE ( 400+inot, 106 ) simulated_time, omega_rot(inot), & omega_gen(inot), torque_gen_old(inot), & torque_total(inot), pitch_add(inot), & torque_gen_old(inot)*omega_gen(inot)*gen_eff, & torque_total(inot)*omega_rot(inot)*air_dens, & thrust_rotor(inot), & wdir(inot)*180.0_wp/pi, & (phi_yaw(inot))*180.0_wp/pi ENDIF ENDIF !-- Set open flag openfile_turb_mod(400+inot)%opened = .TRUE. ENDDO !-- end of loop over turbines ENDIF CALL cpu_log( log_point_s(61), 'wtm_forces', 'stop' ) ! !-- Formats 105 FORMAT ('Turbine control data for turbine ',I2,1X,':'/ & &'----------------------------------------'/ & &' Time RSpeed GSpeed ', & 'GenTorque AeroTorque Pitch Power(Gen) Power(Rot) ', & 'RotThrust WDirection YawOrient') 106 FORMAT (F9.3,2X,F7.3,2X,F7.2,2X,F9.1,3X,F9.1,1X,F6.2,2X,F10.1,2X, & F10.1,1X,F9.1,2X,F7.2,1X,F7.2) END SUBROUTINE wtm_forces !------------------------------------------------------------------------------! ! Description: ! ------------ !> Yaw controller for the wind turbine model !------------------------------------------------------------------------------! SUBROUTINE wtm_yawcontrol( inot ) USE constants USE kinds IMPLICIT NONE INTEGER(iwp) :: inot INTEGER(iwp) :: i_wd_30 REAL(wp) :: missal i_wd_30 = 0_iwp ! !-- The yaw controller computes a 30s running mean of the wind direction. !-- If the difference between turbine alignment and wind direction exceeds !-- 5°, the turbine is yawed. The mechanism stops as soon as the 2s-running !-- mean of the missalignment is smaller than 0.5°. !-- Attention: If the timestep during the simulation changes significantly !-- the lengths of the running means change and it does not correspond to !-- 30s/2s anymore. !-- ! Needs to be modified for these situations ! !-- For wind from the east, the averaging of the wind direction could cause !-- problems and the yaw controller is probably flawed. -> Routine for !-- averaging needs to be improved! ! !-- Check if turbine is not yawing IF ( .NOT. doyaw(inot) ) THEN ! !-- Write current wind direction into array wd30_l = wd30(inot,:) wd30_l = CSHIFT( wd30_l, SHIFT=-1 ) wd30_l(1) = wdir(inot) ! !-- Check if array is full ( no more dummies ) IF ( .NOT. ANY( wd30_l == 999.) ) THEN missal = SUM( wd30_l ) / SIZE( wd30_l ) - phi_yaw(inot) ! !-- Check if turbine is missaligned by more than max_miss IF ( ABS( missal ) > max_miss ) THEN ! !-- Check in which direction to yaw yawdir(inot) = SIGN( 1.0_wp, missal ) ! !-- Start yawing of turbine phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d doyaw(inot) = .TRUE. wd30_l = 999. ! fill with dummies again ENDIF ENDIF wd30(inot,:) = wd30_l ! !-- If turbine is already yawing: !-- Initialize 2 s running mean and yaw until the missalignment is smaller !-- than min_miss ELSE ! !-- Initialize 2 s running mean wd2_l = wd2(inot,:) wd2_l = CSHIFT( wd2_l, SHIFT = -1 ) wd2_l(1) = wdir(inot) ! !-- Check if array is full ( no more dummies ) IF ( .NOT. ANY( wd2_l == 999.0_wp ) ) THEN ! !-- Calculate missalignment of turbine missal = SUM( wd2_l - phi_yaw(inot) ) / SIZE( wd2_l ) ! !-- Check if missalignment is still larger than 0.5 degree and if the !-- yaw direction is still right IF ( ( ABS( missal ) > min_miss ) .AND. & ( yawdir(inot) == SIGN( 1.0_wp, missal ) ) ) THEN ! !-- Continue yawing phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d ELSE ! !-- Stop yawing doyaw(inot) = .FALSE. wd2_l = 999.0_wp ! fill with dummies again ENDIF ELSE ! !-- Continue yawing phi_yaw(inot) = phi_yaw(inot) + yawdir(inot) * yaw_speed * dt_3d ENDIF wd2(inot,:) = wd2_l ENDIF END SUBROUTINE wtm_yawcontrol !------------------------------------------------------------------------------! ! Description: ! ------------ !> Initialization of the speed control !------------------------------------------------------------------------------! SUBROUTINE wtm_init_speed_control IMPLICIT NONE ! !-- If speed control is set, remaining variables and control_parameters for !-- the control algorithm are calculated ! !-- Calculate slope constant for region 15 slope15 = ( slope2 * min_reg2 * min_reg2 ) / ( min_reg2 - min_reg15 ) ! !-- Calculate upper limit of slipage region vs_sysp = rated_genspeed / 1.1_wp ! !-- Calculate slope of slipage region slope25 = ( rated_power / rated_genspeed ) / & ( rated_genspeed - vs_sysp ) ! !-- Calculate lower limit of slipage region min_reg25 = ( slope25 - SQRT( slope25 * ( slope25 - 4.0_wp * & slope2 * vs_sysp ) ) ) / & ( 2.0_wp * slope2 ) ! !-- Frequency for the simple low pass filter Fcorner = 0.25_wp ! !-- At the first timestep the torque is set to its maximum to prevent !-- an overspeeding of the rotor torque_gen_old(:) = max_torque_gen END SUBROUTINE wtm_init_speed_control !------------------------------------------------------------------------------! ! Description: ! ------------ !> Simple controller for the regulation of the rotor speed !------------------------------------------------------------------------------! SUBROUTINE wtm_speed_control( inot ) IMPLICIT NONE INTEGER(iwp) :: inot ! !-- The controller is based on the fortran script from Jonkman !-- et al. 2009 "Definition of a 5 MW Reference Wind Turbine for !-- offshore system developement" ! !-- The generator speed is filtered by a low pass filter !-- for the control of the generator torque lp_coeff = EXP( -2.0_wp * 3.14_wp * dt_3d * Fcorner ) omega_gen_f(inot) = ( 1.0_wp - lp_coeff ) * omega_gen(inot) + lp_coeff *& omega_gen_f_old(inot) IF ( omega_gen_f(inot) <= min_reg15 ) THEN ! !-- Region 1: Generator torque is set to zero to accelerate the rotor: torque_gen(inot) = 0 ELSEIF ( omega_gen_f(inot) <= min_reg2 ) THEN ! !-- Region 1.5: Generator torque is increasing linearly with rotor speed: torque_gen(inot) = slope15 * ( omega_gen_f(inot) - min_reg15 ) ELSEIF ( omega_gen_f(inot) <= min_reg25 ) THEN ! !-- Region 2: Generator torque is increased by the square of the generator !-- speed to keep the TSR optimal: torque_gen(inot) = slope2 * omega_gen_f(inot) * omega_gen_f(inot) ELSEIF ( omega_gen_f(inot) < rated_genspeed ) THEN ! !-- Region 2.5: Slipage region between 2 and 3: torque_gen(inot) = slope25 * ( omega_gen_f(inot) - vs_sysp ) ELSE ! !-- Region 3: Generator torque is antiproportional to the rotor speed to !-- keep the power constant: torque_gen(inot) = rated_power / omega_gen_f(inot) ENDIF ! !-- Calculate torque rate and confine with a max trq_rate = ( torque_gen(inot) - torque_gen_old(inot) ) / dt_3d trq_rate = MIN( MAX( trq_rate, -1.0_wp * max_trq_rate ), max_trq_rate ) ! !-- Calculate new gen torque and confine with max torque torque_gen(inot) = torque_gen_old(inot) + trq_rate * dt_3d torque_gen(inot) = MIN( torque_gen(inot), max_torque_gen ) ! !-- Overwrite values for next timestep omega_rot_l(inot) = omega_gen(inot) / gear_ratio END SUBROUTINE wtm_speed_control !------------------------------------------------------------------------------! ! Description: ! ------------ !> Application of the additional forces generated by the wind turbine on the !> flow components (tendency terms) !> Call for all grid points !------------------------------------------------------------------------------! SUBROUTINE wtm_tendencies( component ) IMPLICIT NONE INTEGER(iwp) :: component !< prognostic variable (u,v,w) INTEGER(iwp) :: i !< running index INTEGER(iwp) :: j !< running index INTEGER(iwp) :: k !< running index SELECT CASE ( component ) CASE ( 1 ) ! !-- Apply the x-component of the force to the u-component of the flow: IF ( simulated_time >= time_turbine_on ) THEN DO i = nxlg, nxrg DO j = nysg, nyng DO k = nzb_u_inner(j,i)+1, k_hub(1) + k_smear(1) ! !-- Calculate the thrust generated by the nacelle and the tower tend_nac_x = 0.5_wp * nac_cd_surf(k,j,i) * & SIGN( u(k,j,i)**2 , u(k,j,i) ) tend_tow_x = 0.5_wp * tow_cd_surf(k,j,i) * & SIGN( u(k,j,i)**2 , u(k,j,i) ) tend(k,j,i) = tend(k,j,i) - rot_tend_x(k,j,i) & - tend_nac_x - tend_tow_x ENDDO ENDDO ENDDO ENDIF CASE ( 2 ) ! !-- Apply the y-component of the force to the v-component of the flow: IF ( simulated_time >= time_turbine_on ) THEN DO i = nxlg, nxrg DO j = nysg, nyng DO k = nzb_v_inner(j,i)+1, k_hub(1) + k_smear(1) tend_nac_y = 0.5_wp * nac_cd_surf(k,j,i) * & SIGN( v(k,j,i)**2 , v(k,j,i) ) tend_tow_y = 0.5_wp * tow_cd_surf(k,j,i) * & SIGN( v(k,j,i)**2 , v(k,j,i) ) tend(k,j,i) = tend(k,j,i) - rot_tend_y(k,j,i) & - tend_nac_y - tend_tow_y ENDDO ENDDO ENDDO ENDIF CASE ( 3 ) ! !-- Apply the z-component of the force to the w-component of the flow: IF ( simulated_time >= time_turbine_on ) THEN DO i = nxlg, nxrg DO j = nysg, nyng DO k = nzb_w_inner(j,i)+1, k_hub(1) + k_smear(1) tend(k,j,i) = tend(k,j,i) - rot_tend_z(k,j,i) ENDDO ENDDO ENDDO ENDIF CASE DEFAULT WRITE( message_string, * ) 'unknown prognostic variable: ', component CALL message( 'wtm_tendencies', 'PA04??', 1, 2, 0, 6, 0 ) END SELECT END SUBROUTINE wtm_tendencies !------------------------------------------------------------------------------! ! Description: ! ------------ !> Application of the additional forces generated by the wind turbine on the !> flow components (tendency terms) !> Call for grid point i,j !------------------------------------------------------------------------------! SUBROUTINE wtm_tendencies_ij( i, j, component ) IMPLICIT NONE INTEGER(iwp) :: component !< prognostic variable (u,v,w) INTEGER(iwp) :: i !< running index INTEGER(iwp) :: j !< running index INTEGER(iwp) :: k !< running index SELECT CASE ( component ) CASE ( 1 ) ! !-- Apply the x-component of the force to the u-component of the flow: IF ( simulated_time >= time_turbine_on ) THEN DO k = nzb_u_inner(j,i)+1, k_hub(1) + k_smear(1) ! !-- Calculate the thrust generated by the nacelle and the tower tend_nac_x = 0.5_wp * nac_cd_surf(k,j,i) * & SIGN( u(k,j,i)**2 , u(k,j,i) ) tend_tow_x = 0.5_wp * tow_cd_surf(k,j,i) * & SIGN( u(k,j,i)**2 , u(k,j,i) ) tend(k,j,i) = tend(k,j,i) - rot_tend_x(k,j,i) & - tend_nac_x - tend_tow_x ENDDO ENDIF CASE ( 2 ) ! !-- Apply the y-component of the force to the v-component of the flow: IF ( simulated_time >= time_turbine_on ) THEN DO k = nzb_v_inner(j,i)+1, k_hub(1) + k_smear(1) tend_nac_y = 0.5_wp * nac_cd_surf(k,j,i) * & SIGN( v(k,j,i)**2 , v(k,j,i) ) tend_tow_y = 0.5_wp * tow_cd_surf(k,j,i) * & SIGN( v(k,j,i)**2 , v(k,j,i) ) tend(k,j,i) = tend(k,j,i) - rot_tend_y(k,j,i) & - tend_nac_y - tend_tow_y ENDDO ENDIF CASE ( 3 ) ! !-- Apply the z-component of the force to the w-component of the flow: IF ( simulated_time >= time_turbine_on ) THEN DO k = nzb_w_inner(j,i)+1, k_hub(1) + k_smear(1) tend(k,j,i) = tend(k,j,i) - rot_tend_z(k,j,i) ENDDO ENDIF CASE DEFAULT WRITE( message_string, * ) 'unknown prognostic variable: ', component CALL message( 'wtm_tendencies', 'PA04??', 1, 2, 0, 6, 0 ) END SELECT END SUBROUTINE wtm_tendencies_ij END MODULE wind_turbine_model_mod