1 | !> @file diffusion_u.f90 |
---|
2 | !------------------------------------------------------------------------------! |
---|
3 | ! This file is part of the PALM model system. |
---|
4 | ! |
---|
5 | ! PALM is free software: you can redistribute it and/or modify it under the |
---|
6 | ! terms of the GNU General Public License as published by the Free Software |
---|
7 | ! Foundation, either version 3 of the License, or (at your option) any later |
---|
8 | ! version. |
---|
9 | ! |
---|
10 | ! PALM is distributed in the hope that it will be useful, but WITHOUT ANY |
---|
11 | ! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR |
---|
12 | ! A PARTICULAR PURPOSE. See the GNU General Public License for more details. |
---|
13 | ! |
---|
14 | ! You should have received a copy of the GNU General Public License along with |
---|
15 | ! PALM. If not, see <http://www.gnu.org/licenses/>. |
---|
16 | ! |
---|
17 | ! Copyright 1997-2020 Leibniz Universitaet Hannover |
---|
18 | !------------------------------------------------------------------------------! |
---|
19 | ! |
---|
20 | ! Current revisions: |
---|
21 | ! ----------------- |
---|
22 | ! |
---|
23 | ! |
---|
24 | ! Former revisions: |
---|
25 | ! ----------------- |
---|
26 | ! $Id: diffusion_u.f90 4360 2020-01-07 11:25:50Z schwenkel $ |
---|
27 | ! Introduction of wall_flags_total_0, which currently sets bits based on static |
---|
28 | ! topography information used in wall_flags_static_0 |
---|
29 | ! |
---|
30 | ! 4329 2019-12-10 15:46:36Z motisi |
---|
31 | ! Renamed wall_flags_0 to wall_flags_static_0 |
---|
32 | ! |
---|
33 | ! 4182 2019-08-22 15:20:23Z scharf |
---|
34 | ! Corrected "Former revisions" section |
---|
35 | ! |
---|
36 | ! 3655 2019-01-07 16:51:22Z knoop |
---|
37 | ! OpenACC port for SPEC |
---|
38 | ! |
---|
39 | ! Revision 1.1 1997/09/12 06:23:51 raasch |
---|
40 | ! Initial revision |
---|
41 | ! |
---|
42 | ! |
---|
43 | ! Description: |
---|
44 | ! ------------ |
---|
45 | !> Diffusion term of the u-component |
---|
46 | !> @todo additional damping (needed for non-cyclic bc) causes bad vectorization |
---|
47 | !> and slows down the speed on NEC about 5-10% |
---|
48 | !------------------------------------------------------------------------------! |
---|
49 | MODULE diffusion_u_mod |
---|
50 | |
---|
51 | |
---|
52 | PRIVATE |
---|
53 | PUBLIC diffusion_u |
---|
54 | |
---|
55 | INTERFACE diffusion_u |
---|
56 | MODULE PROCEDURE diffusion_u |
---|
57 | MODULE PROCEDURE diffusion_u_ij |
---|
58 | END INTERFACE diffusion_u |
---|
59 | |
---|
60 | CONTAINS |
---|
61 | |
---|
62 | |
---|
63 | !------------------------------------------------------------------------------! |
---|
64 | ! Description: |
---|
65 | ! ------------ |
---|
66 | !> Call for all grid points |
---|
67 | !------------------------------------------------------------------------------! |
---|
68 | SUBROUTINE diffusion_u |
---|
69 | |
---|
70 | USE arrays_3d, & |
---|
71 | ONLY: ddzu, ddzw, km, tend, u, v, w, drho_air, rho_air_zw |
---|
72 | |
---|
73 | USE control_parameters, & |
---|
74 | ONLY: constant_top_momentumflux, use_surface_fluxes, & |
---|
75 | use_top_fluxes |
---|
76 | |
---|
77 | USE grid_variables, & |
---|
78 | ONLY: ddx, ddx2, ddy |
---|
79 | |
---|
80 | USE indices, & |
---|
81 | ONLY: nxlu, nxr, nyn, nys, nzb, nzt, wall_flags_total_0 |
---|
82 | |
---|
83 | USE kinds |
---|
84 | |
---|
85 | USE surface_mod, & |
---|
86 | ONLY : surf_def_h, surf_def_v, surf_lsm_h, surf_lsm_v, surf_usm_h, & |
---|
87 | surf_usm_v |
---|
88 | |
---|
89 | IMPLICIT NONE |
---|
90 | |
---|
91 | INTEGER(iwp) :: i !< running index x direction |
---|
92 | INTEGER(iwp) :: j !< running index y direction |
---|
93 | INTEGER(iwp) :: k !< running index z direction |
---|
94 | INTEGER(iwp) :: l !< running index of surface type, south- or north-facing wall |
---|
95 | INTEGER(iwp) :: m !< running index surface elements |
---|
96 | INTEGER(iwp) :: surf_e !< end index of surface elements at (j,i)-gridpoint |
---|
97 | INTEGER(iwp) :: surf_s !< start index of surface elements at (j,i)-gridpoint |
---|
98 | |
---|
99 | REAL(wp) :: flag !< flag to mask topography grid points |
---|
100 | REAL(wp) :: kmym !< diffusion coefficient on southward side of the u-gridbox - interpolated onto xu-yv grid |
---|
101 | REAL(wp) :: kmyp !< diffusion coefficient on northward side of the u-gridbox - interpolated onto xu-yv grid |
---|
102 | REAL(wp) :: kmzm !< diffusion coefficient on bottom of the gridbox - interpolated onto xu-zw grid |
---|
103 | REAL(wp) :: kmzp !< diffusion coefficient on top of the gridbox - interpolated onto xu-zw grid |
---|
104 | REAL(wp) :: mask_bottom !< flag to mask vertical upward-facing surface |
---|
105 | REAL(wp) :: mask_north !< flag to mask vertical surface north of the grid point |
---|
106 | REAL(wp) :: mask_south !< flag to mask vertical surface south of the grid point |
---|
107 | REAL(wp) :: mask_top !< flag to mask vertical downward-facing surface |
---|
108 | |
---|
109 | |
---|
110 | |
---|
111 | !$ACC PARALLEL LOOP COLLAPSE(2) PRIVATE(i, j, k, l, m) & |
---|
112 | !$ACC PRIVATE(surf_e, surf_s, flag, kmym, kmyp, kmzm, kmzp) & |
---|
113 | !$ACC PRIVATE(mask_bottom, mask_north, mask_south, mask_top) & |
---|
114 | !$ACC PRESENT(wall_flags_total_0, km) & |
---|
115 | !$ACC PRESENT(u, v, w) & |
---|
116 | !$ACC PRESENT(ddzu, ddzw, drho_air, rho_air_zw) & |
---|
117 | !$ACC PRESENT(surf_def_h(0:2), surf_def_v(0:1)) & |
---|
118 | !$ACC PRESENT(surf_lsm_h, surf_lsm_v(0:1)) & |
---|
119 | !$ACC PRESENT(surf_usm_h, surf_usm_v(0:1)) & |
---|
120 | !$ACC PRESENT(tend) |
---|
121 | DO i = nxlu, nxr |
---|
122 | DO j = nys, nyn |
---|
123 | ! |
---|
124 | !-- Compute horizontal diffusion |
---|
125 | DO k = nzb+1, nzt |
---|
126 | ! |
---|
127 | !-- Predetermine flag to mask topography and wall-bounded grid points. |
---|
128 | !-- It is sufficient to masked only north- and south-facing surfaces, which |
---|
129 | !-- need special treatment for the u-component. |
---|
130 | flag = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_total_0(k,j,i), 1 ) ) |
---|
131 | mask_south = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_total_0(k,j-1,i), 1 ) ) |
---|
132 | mask_north = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_total_0(k,j+1,i), 1 ) ) |
---|
133 | ! |
---|
134 | !-- Interpolate eddy diffusivities on staggered gridpoints |
---|
135 | kmyp = 0.25_wp * & |
---|
136 | ( km(k,j,i)+km(k,j+1,i)+km(k,j,i-1)+km(k,j+1,i-1) ) |
---|
137 | kmym = 0.25_wp * & |
---|
138 | ( km(k,j,i)+km(k,j-1,i)+km(k,j,i-1)+km(k,j-1,i-1) ) |
---|
139 | |
---|
140 | tend(k,j,i) = tend(k,j,i) & |
---|
141 | + 2.0_wp * ( & |
---|
142 | km(k,j,i) * ( u(k,j,i+1) - u(k,j,i) ) & |
---|
143 | - km(k,j,i-1) * ( u(k,j,i) - u(k,j,i-1) ) & |
---|
144 | ) * ddx2 * flag & |
---|
145 | + ( mask_north * ( & |
---|
146 | kmyp * ( u(k,j+1,i) - u(k,j,i) ) * ddy & |
---|
147 | + kmyp * ( v(k,j+1,i) - v(k,j+1,i-1) ) * ddx & |
---|
148 | ) & |
---|
149 | - mask_south * ( & |
---|
150 | kmym * ( u(k,j,i) - u(k,j-1,i) ) * ddy & |
---|
151 | + kmym * ( v(k,j,i) - v(k,j,i-1) ) * ddx & |
---|
152 | ) & |
---|
153 | ) * ddy * flag |
---|
154 | ENDDO |
---|
155 | ! |
---|
156 | !-- Add horizontal momentum flux u'v' at north- (l=0) and south-facing (l=1) |
---|
157 | !-- surfaces. Note, in the the flat case, loops won't be entered as |
---|
158 | !-- start_index > end_index. Furtermore, note, no vertical natural surfaces |
---|
159 | !-- so far. |
---|
160 | !-- Default-type surfaces |
---|
161 | DO l = 0, 1 |
---|
162 | surf_s = surf_def_v(l)%start_index(j,i) |
---|
163 | surf_e = surf_def_v(l)%end_index(j,i) |
---|
164 | DO m = surf_s, surf_e |
---|
165 | k = surf_def_v(l)%k(m) |
---|
166 | tend(k,j,i) = tend(k,j,i) + & |
---|
167 | surf_def_v(l)%mom_flux_uv(m) * ddy |
---|
168 | ENDDO |
---|
169 | ENDDO |
---|
170 | ! |
---|
171 | !-- Natural-type surfaces |
---|
172 | DO l = 0, 1 |
---|
173 | surf_s = surf_lsm_v(l)%start_index(j,i) |
---|
174 | surf_e = surf_lsm_v(l)%end_index(j,i) |
---|
175 | DO m = surf_s, surf_e |
---|
176 | k = surf_lsm_v(l)%k(m) |
---|
177 | tend(k,j,i) = tend(k,j,i) + & |
---|
178 | surf_lsm_v(l)%mom_flux_uv(m) * ddy |
---|
179 | ENDDO |
---|
180 | ENDDO |
---|
181 | ! |
---|
182 | !-- Urban-type surfaces |
---|
183 | DO l = 0, 1 |
---|
184 | surf_s = surf_usm_v(l)%start_index(j,i) |
---|
185 | surf_e = surf_usm_v(l)%end_index(j,i) |
---|
186 | DO m = surf_s, surf_e |
---|
187 | k = surf_usm_v(l)%k(m) |
---|
188 | tend(k,j,i) = tend(k,j,i) + & |
---|
189 | surf_usm_v(l)%mom_flux_uv(m) * ddy |
---|
190 | ENDDO |
---|
191 | ENDDO |
---|
192 | |
---|
193 | ! |
---|
194 | !-- Compute vertical diffusion. In case of simulating a surface layer, |
---|
195 | !-- respective grid diffusive fluxes are masked (flag 8) within this |
---|
196 | !-- loop, and added further below, else, simple gradient approach is |
---|
197 | !-- applied. Model top is also mask if top-momentum flux is given. |
---|
198 | DO k = nzb+1, nzt |
---|
199 | ! |
---|
200 | !-- Determine flags to mask topography below and above. Flag 1 is |
---|
201 | !-- used to mask topography in general, and flag 8 implies |
---|
202 | !-- information about use_surface_fluxes. Flag 9 is used to control |
---|
203 | !-- momentum flux at model top. |
---|
204 | mask_bottom = MERGE( 1.0_wp, 0.0_wp, & |
---|
205 | BTEST( wall_flags_total_0(k-1,j,i), 8 ) ) |
---|
206 | mask_top = MERGE( 1.0_wp, 0.0_wp, & |
---|
207 | BTEST( wall_flags_total_0(k+1,j,i), 8 ) ) * & |
---|
208 | MERGE( 1.0_wp, 0.0_wp, & |
---|
209 | BTEST( wall_flags_total_0(k+1,j,i), 9 ) ) |
---|
210 | flag = MERGE( 1.0_wp, 0.0_wp, & |
---|
211 | BTEST( wall_flags_total_0(k,j,i), 1 ) ) |
---|
212 | ! |
---|
213 | !-- Interpolate eddy diffusivities on staggered gridpoints |
---|
214 | kmzp = 0.25_wp * & |
---|
215 | ( km(k,j,i)+km(k+1,j,i)+km(k,j,i-1)+km(k+1,j,i-1) ) |
---|
216 | kmzm = 0.25_wp * & |
---|
217 | ( km(k,j,i)+km(k-1,j,i)+km(k,j,i-1)+km(k-1,j,i-1) ) |
---|
218 | |
---|
219 | tend(k,j,i) = tend(k,j,i) & |
---|
220 | + ( kmzp * ( ( u(k+1,j,i) - u(k,j,i) ) * ddzu(k+1) & |
---|
221 | + ( w(k,j,i) - w(k,j,i-1) ) * ddx & |
---|
222 | ) * rho_air_zw(k) * mask_top & |
---|
223 | - kmzm * ( ( u(k,j,i) - u(k-1,j,i) ) * ddzu(k) & |
---|
224 | + ( w(k-1,j,i) - w(k-1,j,i-1) ) * ddx & |
---|
225 | ) * rho_air_zw(k-1) * mask_bottom & |
---|
226 | ) * ddzw(k) * drho_air(k) * flag |
---|
227 | ENDDO |
---|
228 | |
---|
229 | ! |
---|
230 | !-- Vertical diffusion at the first grid point above the surface, |
---|
231 | !-- if the momentum flux at the bottom is given by the Prandtl law or |
---|
232 | !-- if it is prescribed by the user. |
---|
233 | !-- Difference quotient of the momentum flux is not formed over half |
---|
234 | !-- of the grid spacing (2.0*ddzw(k)) any more, since the comparison |
---|
235 | !-- with other (LES) models showed that the values of the momentum |
---|
236 | !-- flux becomes too large in this case. |
---|
237 | !-- The term containing w(k-1,..) (see above equation) is removed here |
---|
238 | !-- because the vertical velocity is assumed to be zero at the surface. |
---|
239 | IF ( use_surface_fluxes ) THEN |
---|
240 | ! |
---|
241 | !-- Default-type surfaces, upward-facing |
---|
242 | surf_s = surf_def_h(0)%start_index(j,i) |
---|
243 | surf_e = surf_def_h(0)%end_index(j,i) |
---|
244 | DO m = surf_s, surf_e |
---|
245 | |
---|
246 | k = surf_def_h(0)%k(m) |
---|
247 | |
---|
248 | tend(k,j,i) = tend(k,j,i) & |
---|
249 | + ( - ( - surf_def_h(0)%usws(m) ) & |
---|
250 | ) * ddzw(k) * drho_air(k) |
---|
251 | ENDDO |
---|
252 | ! |
---|
253 | !-- Default-type surfaces, dowward-facing |
---|
254 | surf_s = surf_def_h(1)%start_index(j,i) |
---|
255 | surf_e = surf_def_h(1)%end_index(j,i) |
---|
256 | DO m = surf_s, surf_e |
---|
257 | |
---|
258 | k = surf_def_h(1)%k(m) |
---|
259 | |
---|
260 | tend(k,j,i) = tend(k,j,i) & |
---|
261 | + ( - surf_def_h(1)%usws(m) & |
---|
262 | ) * ddzw(k) * drho_air(k) |
---|
263 | ENDDO |
---|
264 | ! |
---|
265 | !-- Natural-type surfaces, upward-facing |
---|
266 | surf_s = surf_lsm_h%start_index(j,i) |
---|
267 | surf_e = surf_lsm_h%end_index(j,i) |
---|
268 | DO m = surf_s, surf_e |
---|
269 | |
---|
270 | k = surf_lsm_h%k(m) |
---|
271 | |
---|
272 | tend(k,j,i) = tend(k,j,i) & |
---|
273 | + ( - ( - surf_lsm_h%usws(m) ) & |
---|
274 | ) * ddzw(k) * drho_air(k) |
---|
275 | ENDDO |
---|
276 | ! |
---|
277 | !-- Urban-type surfaces, upward-facing |
---|
278 | surf_s = surf_usm_h%start_index(j,i) |
---|
279 | surf_e = surf_usm_h%end_index(j,i) |
---|
280 | DO m = surf_s, surf_e |
---|
281 | |
---|
282 | k = surf_usm_h%k(m) |
---|
283 | |
---|
284 | tend(k,j,i) = tend(k,j,i) & |
---|
285 | + ( - ( - surf_usm_h%usws(m) ) & |
---|
286 | ) * ddzw(k) * drho_air(k) |
---|
287 | ENDDO |
---|
288 | |
---|
289 | ENDIF |
---|
290 | ! |
---|
291 | !-- Add momentum flux at model top |
---|
292 | IF ( use_top_fluxes .AND. constant_top_momentumflux ) THEN |
---|
293 | surf_s = surf_def_h(2)%start_index(j,i) |
---|
294 | surf_e = surf_def_h(2)%end_index(j,i) |
---|
295 | DO m = surf_s, surf_e |
---|
296 | |
---|
297 | k = surf_def_h(2)%k(m) |
---|
298 | |
---|
299 | tend(k,j,i) = tend(k,j,i) & |
---|
300 | + ( - surf_def_h(2)%usws(m) ) * ddzw(k) * drho_air(k) |
---|
301 | ENDDO |
---|
302 | ENDIF |
---|
303 | |
---|
304 | ENDDO |
---|
305 | ENDDO |
---|
306 | |
---|
307 | END SUBROUTINE diffusion_u |
---|
308 | |
---|
309 | |
---|
310 | !------------------------------------------------------------------------------! |
---|
311 | ! Description: |
---|
312 | ! ------------ |
---|
313 | !> Call for grid point i,j |
---|
314 | !------------------------------------------------------------------------------! |
---|
315 | SUBROUTINE diffusion_u_ij( i, j ) |
---|
316 | |
---|
317 | USE arrays_3d, & |
---|
318 | ONLY: ddzu, ddzw, km, tend, u, v, w, drho_air, rho_air_zw |
---|
319 | |
---|
320 | USE control_parameters, & |
---|
321 | ONLY: constant_top_momentumflux, use_surface_fluxes, & |
---|
322 | use_top_fluxes |
---|
323 | |
---|
324 | USE grid_variables, & |
---|
325 | ONLY: ddx, ddx2, ddy |
---|
326 | |
---|
327 | USE indices, & |
---|
328 | ONLY: nzb, nzt, wall_flags_total_0 |
---|
329 | |
---|
330 | USE kinds |
---|
331 | |
---|
332 | USE surface_mod, & |
---|
333 | ONLY : surf_def_h, surf_def_v, surf_lsm_h, surf_lsm_v, surf_usm_h, & |
---|
334 | surf_usm_v |
---|
335 | |
---|
336 | IMPLICIT NONE |
---|
337 | |
---|
338 | INTEGER(iwp) :: i !< running index x direction |
---|
339 | INTEGER(iwp) :: j !< running index y direction |
---|
340 | INTEGER(iwp) :: k !< running index z direction |
---|
341 | INTEGER(iwp) :: l !< running index of surface type, south- or north-facing wall |
---|
342 | INTEGER(iwp) :: m !< running index surface elements |
---|
343 | INTEGER(iwp) :: surf_e !< End index of surface elements at (j,i)-gridpoint |
---|
344 | INTEGER(iwp) :: surf_s !< Start index of surface elements at (j,i)-gridpoint |
---|
345 | |
---|
346 | REAL(wp) :: flag !< flag to mask topography grid points |
---|
347 | REAL(wp) :: kmym !< diffusion coefficient on southward side of the u-gridbox - interpolated onto xu-yv grid |
---|
348 | REAL(wp) :: kmyp !<diffusion coefficient on northward side of the u-gridbox - interpolated onto xu-yv grid |
---|
349 | REAL(wp) :: kmzm !< diffusion coefficient on bottom of the gridbox - interpolated onto xu-zw grid |
---|
350 | REAL(wp) :: kmzp !< diffusion coefficient on top of the gridbox - interpolated onto xu-zw grid |
---|
351 | REAL(wp) :: mask_bottom !< flag to mask vertical upward-facing surface |
---|
352 | REAL(wp) :: mask_north !< flag to mask vertical surface north of the grid point |
---|
353 | REAL(wp) :: mask_south !< flag to mask vertical surface south of the grid point |
---|
354 | REAL(wp) :: mask_top !< flag to mask vertical downward-facing surface |
---|
355 | ! |
---|
356 | !-- Compute horizontal diffusion |
---|
357 | DO k = nzb+1, nzt |
---|
358 | ! |
---|
359 | !-- Predetermine flag to mask topography and wall-bounded grid points. |
---|
360 | !-- It is sufficient to masked only north- and south-facing surfaces, which |
---|
361 | !-- need special treatment for the u-component. |
---|
362 | flag = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_total_0(k,j,i), 1 ) ) |
---|
363 | mask_south = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_total_0(k,j-1,i), 1 ) ) |
---|
364 | mask_north = MERGE( 1.0_wp, 0.0_wp, BTEST( wall_flags_total_0(k,j+1,i), 1 ) ) |
---|
365 | ! |
---|
366 | !-- Interpolate eddy diffusivities on staggered gridpoints |
---|
367 | kmyp = 0.25_wp * ( km(k,j,i)+km(k,j+1,i)+km(k,j,i-1)+km(k,j+1,i-1) ) |
---|
368 | kmym = 0.25_wp * ( km(k,j,i)+km(k,j-1,i)+km(k,j,i-1)+km(k,j-1,i-1) ) |
---|
369 | |
---|
370 | tend(k,j,i) = tend(k,j,i) & |
---|
371 | + 2.0_wp * ( & |
---|
372 | km(k,j,i) * ( u(k,j,i+1) - u(k,j,i) ) & |
---|
373 | - km(k,j,i-1) * ( u(k,j,i) - u(k,j,i-1) ) & |
---|
374 | ) * ddx2 * flag & |
---|
375 | + ( & |
---|
376 | mask_north * kmyp * ( ( u(k,j+1,i) - u(k,j,i) ) * ddy & |
---|
377 | + ( v(k,j+1,i) - v(k,j+1,i-1) ) * ddx & |
---|
378 | ) & |
---|
379 | - mask_south * kmym * ( ( u(k,j,i) - u(k,j-1,i) ) * ddy & |
---|
380 | + ( v(k,j,i) - v(k,j,i-1) ) * ddx & |
---|
381 | ) & |
---|
382 | ) * ddy * flag |
---|
383 | ENDDO |
---|
384 | |
---|
385 | ! |
---|
386 | !-- Add horizontal momentum flux u'v' at north- (l=0) and south-facing (l=1) |
---|
387 | !-- surfaces. Note, in the the flat case, loops won't be entered as |
---|
388 | !-- start_index > end_index. Furtermore, note, no vertical natural surfaces |
---|
389 | !-- so far. |
---|
390 | !-- Default-type surfaces |
---|
391 | DO l = 0, 1 |
---|
392 | surf_s = surf_def_v(l)%start_index(j,i) |
---|
393 | surf_e = surf_def_v(l)%end_index(j,i) |
---|
394 | DO m = surf_s, surf_e |
---|
395 | k = surf_def_v(l)%k(m) |
---|
396 | tend(k,j,i) = tend(k,j,i) + surf_def_v(l)%mom_flux_uv(m) * ddy |
---|
397 | ENDDO |
---|
398 | ENDDO |
---|
399 | ! |
---|
400 | !-- Natural-type surfaces |
---|
401 | DO l = 0, 1 |
---|
402 | surf_s = surf_lsm_v(l)%start_index(j,i) |
---|
403 | surf_e = surf_lsm_v(l)%end_index(j,i) |
---|
404 | DO m = surf_s, surf_e |
---|
405 | k = surf_lsm_v(l)%k(m) |
---|
406 | tend(k,j,i) = tend(k,j,i) + surf_lsm_v(l)%mom_flux_uv(m) * ddy |
---|
407 | ENDDO |
---|
408 | ENDDO |
---|
409 | ! |
---|
410 | !-- Urban-type surfaces |
---|
411 | DO l = 0, 1 |
---|
412 | surf_s = surf_usm_v(l)%start_index(j,i) |
---|
413 | surf_e = surf_usm_v(l)%end_index(j,i) |
---|
414 | DO m = surf_s, surf_e |
---|
415 | k = surf_usm_v(l)%k(m) |
---|
416 | tend(k,j,i) = tend(k,j,i) + surf_usm_v(l)%mom_flux_uv(m) * ddy |
---|
417 | ENDDO |
---|
418 | ENDDO |
---|
419 | ! |
---|
420 | !-- Compute vertical diffusion. In case of simulating a surface layer, |
---|
421 | !-- respective grid diffusive fluxes are masked (flag 8) within this |
---|
422 | !-- loop, and added further below, else, simple gradient approach is |
---|
423 | !-- applied. Model top is also mask if top-momentum flux is given. |
---|
424 | DO k = nzb+1, nzt |
---|
425 | ! |
---|
426 | !-- Determine flags to mask topography below and above. Flag 1 is |
---|
427 | !-- used to mask topography in general, and flag 8 implies |
---|
428 | !-- information about use_surface_fluxes. Flag 9 is used to control |
---|
429 | !-- momentum flux at model top. |
---|
430 | mask_bottom = MERGE( 1.0_wp, 0.0_wp, & |
---|
431 | BTEST( wall_flags_total_0(k-1,j,i), 8 ) ) |
---|
432 | mask_top = MERGE( 1.0_wp, 0.0_wp, & |
---|
433 | BTEST( wall_flags_total_0(k+1,j,i), 8 ) ) * & |
---|
434 | MERGE( 1.0_wp, 0.0_wp, & |
---|
435 | BTEST( wall_flags_total_0(k+1,j,i), 9 ) ) |
---|
436 | flag = MERGE( 1.0_wp, 0.0_wp, & |
---|
437 | BTEST( wall_flags_total_0(k,j,i), 1 ) ) |
---|
438 | ! |
---|
439 | !-- Interpolate eddy diffusivities on staggered gridpoints |
---|
440 | kmzp = 0.25_wp * ( km(k,j,i)+km(k+1,j,i)+km(k,j,i-1)+km(k+1,j,i-1) ) |
---|
441 | kmzm = 0.25_wp * ( km(k,j,i)+km(k-1,j,i)+km(k,j,i-1)+km(k-1,j,i-1) ) |
---|
442 | |
---|
443 | tend(k,j,i) = tend(k,j,i) & |
---|
444 | + ( kmzp * ( ( u(k+1,j,i) - u(k,j,i) ) * ddzu(k+1) & |
---|
445 | + ( w(k,j,i) - w(k,j,i-1) ) * ddx & |
---|
446 | ) * rho_air_zw(k) * mask_top & |
---|
447 | - kmzm * ( ( u(k,j,i) - u(k-1,j,i) ) * ddzu(k) & |
---|
448 | + ( w(k-1,j,i) - w(k-1,j,i-1) ) * ddx & |
---|
449 | ) * rho_air_zw(k-1) * mask_bottom & |
---|
450 | ) * ddzw(k) * drho_air(k) * flag |
---|
451 | ENDDO |
---|
452 | |
---|
453 | ! |
---|
454 | !-- Vertical diffusion at the first surface grid points, if the |
---|
455 | !-- momentum flux at the bottom is given by the Prandtl law or if it is |
---|
456 | !-- prescribed by the user. |
---|
457 | !-- Difference quotient of the momentum flux is not formed over half of |
---|
458 | !-- the grid spacing (2.0*ddzw(k)) any more, since the comparison with |
---|
459 | !-- other (LES) models showed that the values of the momentum flux becomes |
---|
460 | !-- too large in this case. |
---|
461 | IF ( use_surface_fluxes ) THEN |
---|
462 | ! |
---|
463 | !-- Default-type surfaces, upward-facing |
---|
464 | surf_s = surf_def_h(0)%start_index(j,i) |
---|
465 | surf_e = surf_def_h(0)%end_index(j,i) |
---|
466 | DO m = surf_s, surf_e |
---|
467 | |
---|
468 | k = surf_def_h(0)%k(m) |
---|
469 | |
---|
470 | tend(k,j,i) = tend(k,j,i) & |
---|
471 | + ( - ( - surf_def_h(0)%usws(m) ) & |
---|
472 | ) * ddzw(k) * drho_air(k) |
---|
473 | ENDDO |
---|
474 | ! |
---|
475 | !-- Default-type surfaces, dowward-facing (except for model-top fluxes) |
---|
476 | surf_s = surf_def_h(1)%start_index(j,i) |
---|
477 | surf_e = surf_def_h(1)%end_index(j,i) |
---|
478 | DO m = surf_s, surf_e |
---|
479 | |
---|
480 | k = surf_def_h(1)%k(m) |
---|
481 | |
---|
482 | tend(k,j,i) = tend(k,j,i) & |
---|
483 | + ( - surf_def_h(1)%usws(m) & |
---|
484 | ) * ddzw(k) * drho_air(k) |
---|
485 | ENDDO |
---|
486 | ! |
---|
487 | !-- Natural-type surfaces, upward-facing |
---|
488 | surf_s = surf_lsm_h%start_index(j,i) |
---|
489 | surf_e = surf_lsm_h%end_index(j,i) |
---|
490 | DO m = surf_s, surf_e |
---|
491 | |
---|
492 | k = surf_lsm_h%k(m) |
---|
493 | |
---|
494 | tend(k,j,i) = tend(k,j,i) & |
---|
495 | + ( - ( - surf_lsm_h%usws(m) ) & |
---|
496 | ) * ddzw(k) * drho_air(k) |
---|
497 | ENDDO |
---|
498 | ! |
---|
499 | !-- Urban-type surfaces, upward-facing |
---|
500 | surf_s = surf_usm_h%start_index(j,i) |
---|
501 | surf_e = surf_usm_h%end_index(j,i) |
---|
502 | DO m = surf_s, surf_e |
---|
503 | |
---|
504 | k = surf_usm_h%k(m) |
---|
505 | |
---|
506 | tend(k,j,i) = tend(k,j,i) & |
---|
507 | + ( - ( - surf_usm_h%usws(m) ) & |
---|
508 | ) * ddzw(k) * drho_air(k) |
---|
509 | ENDDO |
---|
510 | |
---|
511 | ENDIF |
---|
512 | ! |
---|
513 | !-- Add momentum flux at model top |
---|
514 | IF ( use_top_fluxes .AND. constant_top_momentumflux ) THEN |
---|
515 | surf_s = surf_def_h(2)%start_index(j,i) |
---|
516 | surf_e = surf_def_h(2)%end_index(j,i) |
---|
517 | DO m = surf_s, surf_e |
---|
518 | |
---|
519 | k = surf_def_h(2)%k(m) |
---|
520 | |
---|
521 | tend(k,j,i) = tend(k,j,i) & |
---|
522 | + ( - surf_def_h(2)%usws(m) ) * ddzw(k) * drho_air(k) |
---|
523 | ENDDO |
---|
524 | ENDIF |
---|
525 | |
---|
526 | |
---|
527 | END SUBROUTINE diffusion_u_ij |
---|
528 | |
---|
529 | END MODULE diffusion_u_mod |
---|