[Nek5000-users] Base velocity problem

[nek5000-users at lists.mcs.anl.gov]

Hi Neks, 

I am bit stuck on this occasion for past 2 days, the code below shows a part of the example called ocyl2.usr (from subroutine my_base_meshv(basev,h1,h2,rhs,msk,tmp) ). This code is to generate a base velocity (where basev=1 at wall of object and 0 at the boundary of the domain). I assume that I have a blending coefficient h1.(using Paul's method or volume of elements method). This subroutine working perfectly for the 2D cases. That is I have the base velocity ranges between 0 and 1. But when I tried it on an aero dynamic foil case(its a 3D case where just 1 element in Y direction), the value of base velocity does not even exceed 0. Almsot all values are like -0.0021564... Could you please tell me is there anything that I have to change in this subroutine to make it working. 

Tha value of m1 and z0 are just explicity giving the base velocity to the elements right? for example on the W or M.V conditions basev becomes 1 and on boundaries of the domain it becomes 0.0 





m1 = -1. 
z0 = 0.0 

nface = 2*ndim 


do e=1,nelv 
do f=1,nface 

c Set Dirichlet for mesh velocity on all boundaries 

if (cbc(f,e,1).ne.'E ') call facev(msk,e,f,z0,nx1,ny1,nz1) 

c Inhomogeneous Dirichlet on cylinder only 

if (cbc(f,e,1).eq.'mv ') then 
call fcaver(xavg,xm1,e,f) 


if (xavg.gt.-3.0) call facev(tmp,e,f,m1,nx1,ny1,nz1) 
endif 
enddo 
enddo 

call axhelm (rhs,tmp,h1,h2,1,1) 

tol = 1.e-4 
imsh = 1 
ifield = 1 
call hmholtz('mshv',basev,rhs,h1,h2,msk,vmult,imsh,tol,200,1) 
call sub2(basev,tmp,n) 

c call outpost(basev,basev,basev,basev,basev,' ') 
c stop 



Regards 
Sijo 

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