[Mudit2208]

Please Help!!! Hello, Can someone please explain how a false diffusion will look like in Lid driven cavity problem. (Reynolds number = 100)
I am using first order upwind scheme for the discretization of convective terms in steady state navier stokes equation and using SIMPLE method.

[FMDenaro]

Originally Posted by Mudit2208

Please Help!!! Hello, Can someone please explain how a false diffusion will look like in Lid driven cavity problem. (Reynolds number = 100)
I am using first order upwind scheme for the discretization of convective terms in steady state navier stokes equation and using SIMPLE method.

You are working on a test-case that has no analytical solution. we already discussed such issue. The numerical diffusion can act as if you are solving the lid-driven cavity at a smaller Re. But that is locally determined by the cfl value. For the steady case you need to consider the grid size.
However, your question is not well stated.

[Mudit]

The grid size i have taken is 65x65 and 21x21. I have generated u, v, p countours, streamlines, u velocity along vertical geometric centre of cavity and v velocity along horizontal centre of cavity. Can we look at false diffusion from here?
I have values to compare from ghia et. al. of u velocity along vertical line and v velocity along horizontal line.

[FMDenaro]

Originally Posted by Mudit

The grid size i have taken is 65x65 and 21x21. I have generated u, v, p countours, streamlines, u velocity along vertical geometric centre of cavity and v velocity along horizontal centre of cavity. Can we look at false diffusion from here?
I have values to compare from ghia et. al. of u velocity along vertical line and v velocity along horizontal line.

You can only perform a grid refinement study and report the velocity profiles at each grid.

[Mudit]

Okay. Thank you so much