Extracting Stream Function from nodal u,v data

Abhijit Tilak

Hi all,

I have a 2-D generalised structured mesh finite volume code based on SIMPLE Scheme. I have another finite element code that can do the mesh adaptation based on Least squares finite element. Currently I am trying out usual driven-cavity flow problem. I dump the nodal data i.e. x,y,u,v,p,T from finite volume code and read it into finite element code. Initially I used vorticity (w) as my mesh adaptation criteria. But the adapted mesh does'nt capture the primary and secondary vortices well. Extracting vorticity from nodal u,v was very easy. many papers I saw recommend using stream-function as adaptation criteria. I am at loss how to extract stream-function values from nodal values of u and v in my finite element code. Here is what I thought would work (but does'nt) {u} = [B]{psi} (B is the shape-func derivative matrix) so {psi} = Inv[B].{u}

Anybody know how to get this done.....

Thanks

Abhijit Tilak.