Solve UV.f90 - Solution of the momentum equations for U and V
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(New page: <pre> !Sample program for solving Lid-driven cavity flow test using SIMPLE-algorithm ! solution of momentum equation for U and V modul !Copyright (C) 2010 Michail Kiričkov !This progra...) |
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! upwind differencing (all other will be included into the source term) | ! upwind differencing (all other will be included into the source term) | ||
- | + | Conv_w = Area_w * ( F(i,j,1) + F(i-1,j ,1) ) * 0.5 | |
- | + | Conv_e = Area_e * ( F(i,j,1) + F(i+1,j ,1) ) * 0.5 | |
Conv_s = Area_s * ( F(i,j,2) + F(i ,j-1,2) ) * 0.5 | Conv_s = Area_s * ( F(i,j,2) + F(i ,j-1,2) ) * 0.5 | ||
Conv_n = Area_n * ( F(i,j,2) + F(i ,j+1,2) ) * 0.5 | Conv_n = Area_n * ( F(i,j,2) + F(i ,j+1,2) ) * 0.5 | ||
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if(i.eq.2 )Conv_w = 0. | if(i.eq.2 )Conv_w = 0. | ||
if(i.eq.NXmax)Conv_e = 0. | if(i.eq.NXmax)Conv_e = 0. | ||
- | + | if(j.eq.2 )Conv_s = 0. | |
if(j.eq.NYmax)Conv_n = 0. | if(j.eq.NYmax)Conv_n = 0. | ||
Revision as of 13:34, 4 May 2010
!Sample program for solving Lid-driven cavity flow test using SIMPLE-algorithm ! solution of momentum equation for U and V modul !Copyright (C) 2010 Michail Kiričkov !This program 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 2 !of the License, or (at your option) any later version. !This program 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 this program; if not, write to the Free Software !Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. !********************************************************************** Subroutine Solve_UV include 'icomm_1.f90' ! calculation of fluxes ! all geometry has rectangular 2D notation Do 100 I= 2,NXmax Do 100 J= 2,NYmax Gam_e = ( Gam(i+1,j ) + Gam(i ,j ) ) * 0.5 Gam_w = ( Gam(i-1,j ) + Gam(i ,j ) ) * 0.5 Gam_s = ( Gam(i ,j-1) + Gam(i ,j ) ) * 0.5 Gam_n = ( Gam(i ,j+1) + Gam(i ,j ) ) * 0.5 !---------------------------------------------------- Area_w = Y(i-1,j)-Y(i-1,j-1) Area_e = Y(i ,j)-Y(i ,j-1) Area_s = X(i,j-1)-X(i-1,j-1) Area_n = X(i,j )-X(i-1,j ) !---------------------------------------------------- Del_w = Xc(i ,j)-Xc(i-1,j) Del_e = Xc(i+1,j)-Xc(i ,j) Del_s = Yc(i,j )-Yc(i,j-1) Del_n = Yc(i,j+1)-Yc(i,j ) !---------------------------------------------------- ! upwind differencing (all other will be included into the source term) Conv_w = Area_w * ( F(i,j,1) + F(i-1,j ,1) ) * 0.5 Conv_e = Area_e * ( F(i,j,1) + F(i+1,j ,1) ) * 0.5 Conv_s = Area_s * ( F(i,j,2) + F(i ,j-1,2) ) * 0.5 Conv_n = Area_n * ( F(i,j,2) + F(i ,j+1,2) ) * 0.5 if(i.eq.2 )Conv_w = 0. if(i.eq.NXmax)Conv_e = 0. if(j.eq.2 )Conv_s = 0. if(j.eq.NYmax)Conv_n = 0. Diff_e = Area_e * Gam_e / Del_e Diff_w = Area_w * Gam_w / Del_w Diff_s = Area_s * Gam_s / Del_s Diff_n = Area_n * Gam_n / Del_n Aw(i,j) = Diff_w + max( Conv_w,0.) Ae(i,j) = Diff_e + max(-1.* Conv_e,0.) As(i,j) = Diff_s + max( Conv_s,0.) An(i,j) = Diff_n + max(-1.* Conv_n,0.) Ap(i,j,1:2)= Aw(i,j) + Ae(i,j) + An(i,j) + As(i,j) Sp(i,j,1:2)= 0. !-------------------------------- HLPA SCHEME---------------------------- ! go to 600 ! (now HLPA is "off") DO 500 nf=1,2 ! Subroutine HLPA(Uw,Fww,Fw,Fp,Fe,Delta_f) if( (i.GT.2).AND.(i.LT.NXmax-0).and.(j.GT.2).AND.(j.LT.NYmax-0) ) then !------------------ w face ------------------- Fww = F(i-2,j,nf) Fw = F(i-1,j,nf) Fp = F(i ,j,nf) Fe = F(i+1,j,nf) call HLPA(Conv_w,Fww,Fw,Fp,Fe,Delta_f) Sp(i,j,nf) = Sp(i,j,nf) + Conv_w * Delta_f !------------------ e face-------------------- Fww = F(i-1,j,nf) Fw = F(i ,j,nf) Fp = F(i+1,j,nf) Fe = F(i+2,j,nf) call HLPA(Conv_e,Fww,Fw,Fp,Fe,Delta_f) Sp(i,j,nf) = Sp(i,j,nf) + Conv_e * Delta_f * (-1.) !------------------ s face-------------------- Fww = F(i ,j-2,nf) Fw = F(i ,j-1,nf) Fp = F(i ,j ,nf) Fe = F(i ,j+1,nf) call HLPA(Conv_s,Fww,Fw,Fp,Fe,Delta_f) Sp(i,j,nf) = Sp(i,j,nf) + Conv_s * Delta_f !------------------ n face-------------------- Fww = F(i ,j-1,nf) Fw = F(i ,j ,nf) Fp = F(i ,j+1,nf) Fe = F(i ,j+2,nf) call HLPA(Conv_n,Fww,Fw,Fp,Fe,Delta_f) Sp(i,j,nf) = Sp(i,j,nf) + Conv_n * Delta_f *(-1.) end if 500 continue 600 continue !------------------------------------------------------------------------ 100 continue ! coefficient cycle !----------------------------- pressure gradient ------------------------ Do 200 I= 2,NXmax Do 200 J= 2,NYmax DX = X(i,j) - X(i-1,j) DY = Y(i,j) - Y(i,j-1) VOL = DX * DY PE = ( F(i,j,4) + F(i+1,j,4) ) * 0.5 PW = ( F(i,j,4) + F(i-1,j,4) ) * 0.5 PN = ( F(i,j,4) + F(i,j+1,4) ) * 0.5 PS = ( F(i,j,4) + F(i,j-1,4) ) * 0.5 DPx_c(i,j) = (PE-PW)/DX DPy_c(i,j) = (PN-PS)/DY Sp(i,j,1) = Sp(i,j,1) - DPx_c(i,j) * VOL Sp(i,j,2) = Sp(i,j,2) - DPy_c(i,j) * VOL 200 continue !---------------------------- under-relaxation --------------------------------- Alfa = 0.85 Urf = 1. / Alfa Ap(1:NXmaxC,1:NYmaxC,1) = Ap(1:NXmaxC,1:NYmaxC,1) * Urf Sp(1:NXmaxC,1:NYmaxC,1) = Sp(1:NXmaxC,1:NYmaxC,1) + (1. - Alfa )* Ap(1:NXmaxC,1:NYmaxC,1)*F(1:NXmaxC,1:NYmaxC,1) ! / Alfa Ap(1:NXmaxC,1:NYmaxC,2) = Ap(1:NXmaxC,1:NYmaxC,2) * Urf Sp(1:NXmaxC,1:NYmaxC,2) = Sp(1:NXmaxC,1:NYmaxC,2) + (1. - Alfa )* Ap(1:NXmaxC,1:NYmaxC,2)*F(1:NXmaxC,1:NYmaxC,2) ! / Alfa !--------------------------------------------------------------------------------- !****************************************************************** niter = 0 write(*,*)'solve U' call Convergence_Criteria(1,Res_sum_before) 10 continue niter= niter + 1 Call TDMA_1(1) call Convergence_Criteria(1,Res_sum_After) If((abs(Res_sum_before-Res_sum_After).Ge.0.00000000001).and.niter.le.20)then Res_sum_before = Res_sum_After go to 10 End if niter = 0 write(*,*)'solve V' call Convergence_Criteria(2,Res_sum_before) 20 continue niter= niter + 1 Call TDMA_1(2) call Convergence_Criteria(2,Res_sum_After) If((abs(Res_sum_before-Res_sum_After).Ge.0.00000000001).and.niter.le.20)then Res_sum_before = Res_sum_After go to 20 End if !*********************************************************************** !--------------------------------------------------------------------------------- Return End