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source: palm/trunk/SOURCE/boundary_conds.f90 @ 96

Last change on this file since 96 was 95, checked in by raasch, 18 years ago
further preliminary uncomplete changes for ocean version
Property svn:keywords set to `Id`
File size: 17.7 KB

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1	SUBROUTINE boundary_conds( range )
2
3	!------------------------------------------------------------------------------!
4	! Actual revisions:
5	! -----------------
6	! Boundary conditions for salinity added
7	!
8	! Former revisions:
9	! -----------------
10	! $Id: boundary_conds.f90 95 2007-06-02 16:48:38Z raasch $
11	!
12	! 75 2007-03-22 09:54:05Z raasch
13	! The "main" part sets conditions for time level t+dt instead of level t,
14	! outflow boundary conditions changed from Neumann to radiation condition,
15	! uxrp, vynp eliminated, moisture renamed humidity
16	!
17	! 19 2007-02-23 04:53:48Z raasch
18	! Boundary conditions for e(nzt), pt(nzt), and q(nzt) removed because these
19	! gridpoints are now calculated by the prognostic equation,
20	! Dirichlet and zero gradient condition for pt established at top boundary
21	!
22	! RCS Log replace by Id keyword, revision history cleaned up
23	!
24	! Revision 1.15 2006/02/23 09:54:55 raasch
25	! Surface boundary conditions in case of topography: nzb replaced by
26	! 2d-k-index-arrays (nzb_w_inner, etc.). Conditions for u and v remain
27	! unchanged (still using nzb) because a non-flat topography must use a
28	! Prandtl-layer, which don't requires explicit setting of the surface values.
29	!
30	! Revision 1.1 1997/09/12 06:21:34 raasch
31	! Initial revision
32	!
33	!
34	! Description:
35	! ------------
36	! Boundary conditions for the prognostic quantities (range='main').
37	! In case of non-cyclic lateral boundaries the conditions for velocities at
38	! the outflow are set after the pressure solver has been called (range=
39	! 'outflow_uvw').
40	! One additional bottom boundary condition is applied for the TKE (=(u)*2)
41	! in prandtl_fluxes. The cyclic lateral boundary conditions are implicitly
42	! handled in routine exchange_horiz. Pressure boundary conditions are
43	! explicitly set in routines pres, poisfft, poismg and sor.
44	!------------------------------------------------------------------------------!
45
46	USE arrays_3d
47	USE control_parameters
48	USE grid_variables
49	USE indices
50	USE pegrid
51
52	IMPLICIT NONE
53
54	CHARACTER (LEN=*) :: range
55
56	INTEGER :: i, j, k
57
58	REAL :: c_max, c_u, c_v, c_w, denom
59
60
61	IF ( range == 'main') THEN
62	!
63	!-- Bottom boundary
64	IF ( ibc_uv_b == 0 ) THEN
65	!
66	!-- Satisfying the Dirichlet condition with an extra layer below the
67	!-- surface where the u and v component change their sign
68	u_p(nzb,:,:) = -u_p(nzb+1,:,:)
69	v_p(nzb,:,:) = -v_p(nzb+1,:,:)
70	ELSE
71	u_p(nzb,:,:) = u_p(nzb+1,:,:)
72	v_p(nzb,:,:) = v_p(nzb+1,:,:)
73	ENDIF
74	DO i = nxl-1, nxr+1
75	DO j = nys-1, nyn+1
76	w_p(nzb_w_inner(j,i),j,i) = 0.0
77	ENDDO
78	ENDDO
79
80	!
81	!-- Top boundary
82	IF ( ibc_uv_t == 0 ) THEN
83	u_p(nzt+1,:,:) = ug(nzt+1)
84	v_p(nzt+1,:,:) = vg(nzt+1)
85	ELSE
86	u_p(nzt+1,:,:) = u_p(nzt,:,:)
87	v_p(nzt+1,:,:) = v_p(nzt,:,:)
88	ENDIF
89	w_p(nzt:nzt+1,:,:) = 0.0 ! nzt is not a prognostic level (but cf. pres)
90
91	!
92	!-- Temperature at bottom boundary
93	IF ( ibc_pt_b == 0 ) THEN
94	DO i = nxl-1, nxr+1
95	DO j = nys-1, nyn+1
96	pt_p(nzb_s_inner(j,i),j,i) = pt(nzb_s_inner(j,i),j,i)
97	ENDDO
98	ENDDO
99	ELSE
100	DO i = nxl-1, nxr+1
101	DO j = nys-1, nyn+1
102	pt_p(nzb_s_inner(j,i),j,i) = pt_p(nzb_s_inner(j,i)+1,j,i)
103	ENDDO
104	ENDDO
105	ENDIF
106
107	!
108	!-- Temperature at top boundary
109	IF ( ibc_pt_t == 0 ) THEN
110	pt_p(nzt+1,:,:) = pt(nzt+1,:,:)
111	ELSEIF ( ibc_pt_t == 1 ) THEN
112	pt_p(nzt+1,:,:) = pt_p(nzt,:,:)
113	ELSEIF ( ibc_pt_t == 2 ) THEN
114	pt_p(nzt+1,:,:) = pt_p(nzt,:,:) + bc_pt_t_val * dzu(nzt+1)
115	ENDIF
116
117	!
118	!-- Boundary conditions for TKE
119	!-- Generally Neumann conditions with de/dz=0 are assumed
120	IF ( .NOT. constant_diffusion ) THEN
121	DO i = nxl-1, nxr+1
122	DO j = nys-1, nyn+1
123	e_p(nzb_s_inner(j,i),j,i) = e_p(nzb_s_inner(j,i)+1,j,i)
124	ENDDO
125	ENDDO
126	e_p(nzt+1,:,:) = e_p(nzt,:,:)
127	ENDIF
128
129	!
130	!-- Boundary conditions for salinity
131	IF ( ocean ) THEN
132	!
133	!-- Bottom boundary: Neumann condition because salinity flux is always
134	!-- given
135	DO i = nxl-1, nxr+1
136	DO j = nys-1, nyn+1
137	sa_p(nzb_s_inner(j,i),j,i) = sa_p(nzb_s_inner(j,i)+1,j,i)
138	ENDDO
139	ENDDO
140
141	!
142	!-- Top boundary: Dirichlet or Neumann
143	IF ( ibc_sa_t == 0 ) THEN
144	sa_p(nzt+1,:,:) = sa(nzt+1,:,:)
145	ELSEIF ( ibc_sa_t == 1 ) THEN
146	sa_p(nzt+1,:,:) = sa_p(nzt,:,:)
147	ENDIF
148
149	ENDIF
150
151	!
152	!-- Boundary conditions for total water content or scalar,
153	!-- bottom and top boundary (see also temperature)
154	IF ( humidity .OR. passive_scalar ) THEN
155	!
156	!-- Surface conditions for constant_humidity_flux
157	IF ( ibc_q_b == 0 ) THEN
158	DO i = nxl-1, nxr+1
159	DO j = nys-1, nyn+1
160	q_p(nzb_s_inner(j,i),j,i) = q(nzb_s_inner(j,i),j,i)
161	ENDDO
162	ENDDO
163	ELSE
164	DO i = nxl-1, nxr+1
165	DO j = nys-1, nyn+1
166	q_p(nzb_s_inner(j,i),j,i) = q_p(nzb_s_inner(j,i)+1,j,i)
167	ENDDO
168	ENDDO
169	ENDIF
170	!
171	!-- Top boundary
172	q_p(nzt+1,:,:) = q_p(nzt,:,:) + bc_q_t_val * dzu(nzt+1)
173	ENDIF
174
175	!
176	!-- Lateral boundary conditions at the inflow. Quasi Neumann conditions
177	!-- are needed for the wall normal velocity in order to ensure zero
178	!-- divergence. Dirichlet conditions are used for all other quantities.
179	IF ( inflow_s ) THEN
180	v_p(:,nys,:) = v_p(:,nys-1,:)
181	ELSEIF ( inflow_n ) THEN
182	v_p(:,nyn,:) = v_p(:,nyn+1,:)
183	ELSEIF ( inflow_l ) THEN
184	u_p(:,:,nxl) = u_p(:,:,nxl-1)
185	ELSEIF ( inflow_r ) THEN
186	u_p(:,:,nxr) = u_p(:,:,nxr+1)
187	ENDIF
188
189	!
190	!-- Lateral boundary conditions for scalar quantities at the outflow
191	IF ( outflow_s ) THEN
192	pt_p(:,nys-1,:) = pt_p(:,nys,:)
193	IF ( .NOT. constant_diffusion ) e_p(:,nys-1,:) = e_p(:,nys,:)
194	IF ( humidity .OR. passive_scalar ) q_p(:,nys-1,:) = q_p(:,nys,:)
195	ELSEIF ( outflow_n ) THEN
196	pt_p(:,nyn+1,:) = pt_p(:,nyn,:)
197	IF ( .NOT. constant_diffusion ) e_p(:,nyn+1,:) = e_p(:,nyn,:)
198	IF ( humidity .OR. passive_scalar ) q_p(:,nyn+1,:) = q_p(:,nyn,:)
199	ELSEIF ( outflow_l ) THEN
200	pt_p(:,:,nxl-1) = pt_p(:,:,nxl)
201	IF ( .NOT. constant_diffusion ) e_p(:,:,nxl-1) = e_p(:,:,nxl)
202	IF ( humidity .OR. passive_scalar ) q_p(:,:,nxl-1) = q_p(:,:,nxl)
203	ELSEIF ( outflow_r ) THEN
204	pt_p(:,:,nxr+1) = pt_p(:,:,nxr)
205	IF ( .NOT. constant_diffusion ) e_p(:,:,nxr+1) = e_p(:,:,nxr)
206	IF ( humidity .OR. passive_scalar ) q_p(:,:,nxr+1) = q_p(:,:,nxr)
207	ENDIF
208
209	ENDIF
210
211	!
212	!-- Radiation boundary condition for the velocities at the respective outflow
213	IF ( outflow_s .AND. &
214	intermediate_timestep_count == intermediate_timestep_count_max ) &
215	THEN
216
217	c_max = dy / dt_3d
218
219	DO i = nxl-1, nxr+1
220	DO k = nzb+1, nzt+1
221
222	!
223	!-- First calculate the phase speeds for u,v, and w
224	denom = u_m_s(k,0,i) - u_m_s(k,1,i)
225
226	IF ( denom /= 0.0 ) THEN
227	c_u = -c_max * ( u(k,0,i) - u_m_s(k,0,i) ) / denom
228	IF ( c_u < 0.0 ) THEN
229	c_u = 0.0
230	ELSEIF ( c_u > c_max ) THEN
231	c_u = c_max
232	ENDIF
233	ELSE
234	c_u = c_max
235	ENDIF
236	denom = v_m_s(k,0,i) - v_m_s(k,1,i)
237
238	IF ( denom /= 0.0 ) THEN
239	c_v = -c_max * ( v(k,0,i) - v_m_s(k,0,i) ) / denom
240	IF ( c_v < 0.0 ) THEN
241	c_v = 0.0
242	ELSEIF ( c_v > c_max ) THEN
243	c_v = c_max
244	ENDIF
245	ELSE
246	c_v = c_max
247	ENDIF
248
249	denom = w_m_s(k,0,i) - w_m_s(k,1,i)
250
251	IF ( denom /= 0.0 ) THEN
252	c_w = -c_max * ( w(k,0,i) - w_m_s(k,0,i) ) / denom
253	IF ( c_w < 0.0 ) THEN
254	c_w = 0.0
255	ELSEIF ( c_w > c_max ) THEN
256	c_w = c_max
257	ENDIF
258	ELSE
259	c_w = c_max
260	ENDIF
261
262	!
263	!-- Calculate the new velocities
264	u_p(k,-1,i) = u(k,-1,i) + dt_3d * c_u * &
265	( u(k,-1,i) - u(k,0,i) ) * ddy
266
267	v_p(k,-1,i) = v(k,-1,i) + dt_3d * c_v * &
268	( v(k,-1,i) - v_m_s(k,0,i) ) * ddy
269
270	w_p(k,-1,i) = w(k,-1,i) + dt_3d * c_w * &
271	( w(k,-1,i) - w(k,0,i) ) * ddy
272
273	!
274	!-- Save old timelevels for the next timestep
275	u_m_s(k,:,i) = u(k,-1:1,i)
276	v_m_s(k,:,i) = v(k,-1:1,i)
277	w_m_s(k,:,i) = w(k,-1:1,i)
278
279	ENDDO
280	ENDDO
281
282	!
283	!-- Bottom boundary at the outflow
284	IF ( ibc_uv_b == 0 ) THEN
285	u_p(nzb,-1,:) = -u_p(nzb+1,-1,:)
286	v_p(nzb,-1,:) = -v_p(nzb+1,-1,:)
287	ELSE
288	u_p(nzb,-1,:) = u_p(nzb+1,-1,:)
289	v_p(nzb,-1,:) = v_p(nzb+1,-1,:)
290	ENDIF
291	w_p(nzb,ny+1,:) = 0.0
292
293	!
294	!-- Top boundary at the outflow
295	IF ( ibc_uv_t == 0 ) THEN
296	u_p(nzt+1,-1,:) = ug(nzt+1)
297	v_p(nzt+1,-1,:) = vg(nzt+1)
298	ELSE
299	u_p(nzt+1,-1,:) = u(nzt,-1,:)
300	v_p(nzt+1,-1,:) = v(nzt,-1,:)
301	ENDIF
302	w_p(nzt:nzt+1,-1,:) = 0.0
303
304	ENDIF
305
306	IF ( outflow_n .AND. &
307	intermediate_timestep_count == intermediate_timestep_count_max ) &
308	THEN
309
310	c_max = dy / dt_3d
311
312	DO i = nxl-1, nxr+1
313	DO k = nzb+1, nzt+1
314
315	!
316	!-- First calculate the phase speeds for u,v, and w
317	denom = u_m_n(k,ny,i) - u_m_n(k,ny-1,i)
318
319	IF ( denom /= 0.0 ) THEN
320	c_u = -c_max * ( u(k,ny,i) - u_m_n(k,ny,i) ) / denom
321	IF ( c_u < 0.0 ) THEN
322	c_u = 0.0
323	ELSEIF ( c_u > c_max ) THEN
324	c_u = c_max
325	ENDIF
326	ELSE
327	c_u = c_max
328	ENDIF
329
330	denom = v_m_n(k,ny,i) - v_m_n(k,ny-1,i)
331
332	IF ( denom /= 0.0 ) THEN
333	c_v = -c_max * ( v(k,ny,i) - v_m_n(k,ny,i) ) / denom
334	IF ( c_v < 0.0 ) THEN
335	c_v = 0.0
336	ELSEIF ( c_v > c_max ) THEN
337	c_v = c_max
338	ENDIF
339	ELSE
340	c_v = c_max
341	ENDIF
342
343	denom = w_m_n(k,ny,i) - w_m_n(k,ny-1,i)
344
345	IF ( denom /= 0.0 ) THEN
346	c_w = -c_max * ( w(k,ny,i) - w_m_n(k,ny,i) ) / denom
347	IF ( c_w < 0.0 ) THEN
348	c_w = 0.0
349	ELSEIF ( c_w > c_max ) THEN
350	c_w = c_max
351	ENDIF
352	ELSE
353	c_w = c_max
354	ENDIF
355
356	!
357	!-- Calculate the new velocities
358	u_p(k,ny+1,i) = u(k,ny+1,i) - dt_3d * c_u * &
359	( u(k,ny+1,i) - u(k,ny,i) ) * ddy
360
361	v_p(k,ny+1,i) = v(k,ny+1,i) - dt_3d * c_v * &
362	( v(k,ny+1,i) - v(k,ny,i) ) * ddy
363
364	w_p(k,ny+1,i) = w(k,ny+1,i) - dt_3d * c_w * &
365	( w(k,ny+1,i) - w(k,ny,i) ) * ddy
366
367	!
368	!-- Swap timelevels for the next timestep
369	u_m_n(k,:,i) = u(k,ny-1:ny+1,i)
370	v_m_n(k,:,i) = v(k,ny-1:ny+1,i)
371	w_m_n(k,:,i) = w(k,ny-1:ny+1,i)
372
373	ENDDO
374	ENDDO
375
376	!
377	!-- Bottom boundary at the outflow
378	IF ( ibc_uv_b == 0 ) THEN
379	u_p(nzb,ny+1,:) = -u_p(nzb+1,ny+1,:)
380	v_p(nzb,ny+1,:) = -v_p(nzb+1,ny+1,:)
381	ELSE
382	u_p(nzb,ny+1,:) = u_p(nzb+1,ny+1,:)
383	v_p(nzb,ny+1,:) = v_p(nzb+1,ny+1,:)
384	ENDIF
385	w_p(nzb,ny+1,:) = 0.0
386
387	!
388	!-- Top boundary at the outflow
389	IF ( ibc_uv_t == 0 ) THEN
390	u_p(nzt+1,ny+1,:) = ug(nzt+1)
391	v_p(nzt+1,ny+1,:) = vg(nzt+1)
392	ELSE
393	u_p(nzt+1,ny+1,:) = u_p(nzt,nyn+1,:)
394	v_p(nzt+1,ny+1,:) = v_p(nzt,nyn+1,:)
395	ENDIF
396	w_p(nzt:nzt+1,ny+1,:) = 0.0
397
398	ENDIF
399
400	IF ( outflow_l .AND. &
401	intermediate_timestep_count == intermediate_timestep_count_max ) &
402	THEN
403
404	c_max = dx / dt_3d
405
406	DO j = nys-1, nyn+1
407	DO k = nzb+1, nzt+1
408
409	!
410	!-- First calculate the phase speeds for u,v, and w
411	denom = u_m_l(k,j,0) - u_m_l(k,j,1)
412
413	IF ( denom /= 0.0 ) THEN
414	c_u = -c_max * ( u(k,j,0) - u_m_r(k,j,0) ) / denom
415	IF ( c_u > 0.0 ) THEN
416	c_u = 0.0
417	ELSEIF ( c_u < -c_max ) THEN
418	c_u = -c_max
419	ENDIF
420	ELSE
421	c_u = -c_max
422	ENDIF
423
424	denom = v_m_l(k,j,0) - v_m_l(k,j,1)
425
426	IF ( denom /= 0.0 ) THEN
427	c_v = -c_max * ( v(k,j,0) - v_m_l(k,j,0) ) / denom
428	IF ( c_v < 0.0 ) THEN
429	c_v = 0.0
430	ELSEIF ( c_v > c_max ) THEN
431	c_v = c_max
432	ENDIF
433	ELSE
434	c_v = c_max
435	ENDIF
436
437	denom = w_m_l(k,j,0) - w_m_l(k,j,1)
438
439	IF ( denom /= 0.0 ) THEN
440	c_w = -c_max * ( w(k,j,0) - w_m_l(k,j,0) ) / denom
441	IF ( c_w < 0.0 ) THEN
442	c_w = 0.0
443	ELSEIF ( c_w > c_max ) THEN
444	c_w = c_max
445	ENDIF
446	ELSE
447	c_w = c_max
448	ENDIF
449
450	!
451	!-- Calculate the new velocities
452	u_p(k,j,-1) = u(k,j,-1) + dt_3d * c_u * &
453	( u(k,j,-1) - u(k,j,0) ) * ddx
454
455	v_p(k,j,-1) = v(k,j,-1) + dt_3d * c_v * &
456	( v(k,j,-1) - v(k,j,0) ) * ddx
457
458	w_p(k,j,-1) = w(k,j,-1) + dt_3d * c_w * &
459	( w(k,j,-1) - w(k,j,0) ) * ddx
460
461	!
462	!-- Swap timelevels for the next timestep
463	u_m_l(k,j,:) = u(k,j,-1:1)
464	v_m_l(k,j,:) = v(k,j,-1:1)
465	w_m_l(k,j,:) = w(k,j,-1:1)
466
467	ENDDO
468	ENDDO
469
470	!
471	!-- Bottom boundary at the outflow
472	IF ( ibc_uv_b == 0 ) THEN
473	u_p(nzb,:,-1) = -u_p(nzb+1,:,-1)
474	v_p(nzb,:,-1) = -v_p(nzb+1,:,-1)
475	ELSE
476	u_p(nzb,:,-1) = u_p(nzb+1,:,-1)
477	v_p(nzb,:,-1) = v_p(nzb+1,:,-1)
478	ENDIF
479	w_p(nzb,:,-1) = 0.0
480
481	!
482	!-- Top boundary at the outflow
483	IF ( ibc_uv_t == 0 ) THEN
484	u_p(nzt+1,:,-1) = ug(nzt+1)
485	v_p(nzt+1,:,-1) = vg(nzt+1)
486	ELSE
487	u_p(nzt+1,:,-1) = u_p(nzt,:,-1)
488	v_p(nzt+1,:,-1) = v_p(nzt,:,-1)
489	ENDIF
490	w_p(nzt:nzt+1,:,-1) = 0.0
491
492	ENDIF
493
494	IF ( outflow_r .AND. &
495	intermediate_timestep_count == intermediate_timestep_count_max ) &
496	THEN
497
498	c_max = dx / dt_3d
499
500	DO j = nys-1, nyn+1
501	DO k = nzb+1, nzt+1
502
503	!
504	!-- First calculate the phase speeds for u,v, and w
505	denom = u_m_r(k,j,nx) - u_m_r(k,j,nx-1)
506
507	IF ( denom /= 0.0 ) THEN
508	c_u = -c_max * ( u(k,j,nx) - u_m_r(k,j,nx) ) / denom
509	IF ( c_u < 0.0 ) THEN
510	c_u = 0.0
511	ELSEIF ( c_u > c_max ) THEN
512	c_u = c_max
513	ENDIF
514	ELSE
515	c_u = c_max
516	ENDIF
517
518	denom = v_m_r(k,j,nx) - v_m_r(k,j,nx-1)
519
520	IF ( denom /= 0.0 ) THEN
521	c_v = -c_max * ( v(k,j,nx) - v_m_r(k,j,nx) ) / denom
522	IF ( c_v < 0.0 ) THEN
523	c_v = 0.0
524	ELSEIF ( c_v > c_max ) THEN
525	c_v = c_max
526	ENDIF
527	ELSE
528	c_v = c_max
529	ENDIF
530
531	denom = w_m_r(k,j,nx) - w_m_r(k,j,nx-1)
532
533	IF ( denom /= 0.0 ) THEN
534	c_w = -c_max * ( w(k,j,nx) - w_m_r(k,j,nx) ) / denom
535	IF ( c_w < 0.0 ) THEN
536	c_w = 0.0
537	ELSEIF ( c_w > c_max ) THEN
538	c_w = c_max
539	ENDIF
540	ELSE
541	c_w = c_max
542	ENDIF
543
544	!
545	!-- Calculate the new velocities
546	u_p(k,j,nx+1) = u(k,j,nx+1) - dt_3d * c_u * &
547	( u(k,j,nx+1) - u(k,j,nx) ) * ddx
548
549	v_p(k,j,nx+1) = v(k,j,nx+1) - dt_3d * c_v * &
550	( v(k,j,nx+1) - v(k,j,nx) ) * ddx
551
552	w_p(k,j,nx+1) = w(k,j,nx+1) - dt_3d * c_w * &
553	( w(k,j,nx+1) - w(k,j,nx) ) * ddx
554
555	!
556	!-- Swap timelevels for the next timestep
557	u_m_r(k,j,:) = u(k,j,nx-1:nx+1)
558	v_m_r(k,j,:) = v(k,j,nx-1:nx+1)
559	w_m_r(k,j,:) = w(k,j,nx-1:nx+1)
560
561	ENDDO
562	ENDDO
563
564	!
565	!-- Bottom boundary at the outflow
566	IF ( ibc_uv_b == 0 ) THEN
567	u_p(nzb,:,nx+1) = -u_p(nzb+1,:,nx+1)
568	v_p(nzb,:,nx+1) = -v_p(nzb+1,:,nx+1)
569	ELSE
570	u_p(nzb,:,nx+1) = u_p(nzb+1,:,nx+1)
571	v_p(nzb,:,nx+1) = v_p(nzb+1,:,nx+1)
572	ENDIF
573	w_p(nzb,:,nx+1) = 0.0
574
575	!
576	!-- Top boundary at the outflow
577	IF ( ibc_uv_t == 0 ) THEN
578	u_p(nzt+1,:,nx+1) = ug(nzt+1)
579	v_p(nzt+1,:,nx+1) = vg(nzt+1)
580	ELSE
581	u_p(nzt+1,:,nx+1) = u_p(nzt,:,nx+1)
582	v_p(nzt+1,:,nx+1) = v_p(nzt,:,nx+1)
583	ENDIF
584	w(nzt:nzt+1,:,nx+1) = 0.0
585
586	ENDIF
587
588
589	END SUBROUTINE boundary_conds

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