Hi,

I am a M.Tech Student with a final year project in Multigrid Methods for Euler equations. My project is to implement upwind based multigrid transfer operators to improve the FAS multigrid for supersonic and hypersonic flows.

My problem is implementing the multigrid operators near the boundary cell especially for prolongation or interpolation operator which transfers the correction from coarse to fine grids. I have two questions here.

My question is do I have to take into account the correction at the ghost cells (for implementing BCs) while considering the correction at the cells adjacent to the boundary (for example cells immediate to the wall). This is for normal elliptic operator with bilinear interpolation.

For upwind based operators (like the one followed in the paper by Koren and Hemker (1991)) how will the upwinding should be done for interpolation operators for the cells near the boundary?

Looking forward to your reply. Thanks in advance.

With regards

VidhyaShankar

Hi, I am working in incompressible flows using multigrid FAS method. For what type of problems are you solving. Hope our discussion may help us.

Hi,

I am working on subsonic, transonic, supersonic and hypersonic flows. The multigrid method is working for subsonic and transonic flows. But I do have a problem with interpolation. That too for the boundary cells. How do I do the interpolation near the boundary. If you can help me I shall be grateful...

With regards

Vidhyashankar