Learning Forum

[Kubrider]

Hello ansys community,

I am trying to solve the case but don´t know how to properly judge the convergence. Because the case is not converging under 10^-3 residuals of continuity after 1500 iteration and it is looking that they are stagnating.

In simulation I use a 

- pressure based solver

- turbulent model realizable k-epsilon

- standard wall

Boundary conditions:

- velocity inlet 11.6 ms^-1

- two pressure outlets

Mesh

Minimum Orthogonal Quality =  1.24974e-02.

There are the residuals

 

I appreciate every advice how to judge convergence. Thanks.

[DrAmine]

Very low ortho quality what about mesh metrics? Can you add screenshot of mesh geometry..? Also judging convergence is not only made by looking into residual the evolution of key quantities like drag or holdup or temperature in certain region or at certain point is important.

[Kubrider]

I know that ortho quality is low but i did not find the way how to get better ortho quality. After adding inflation layer orthogonal quality fall on lower numbers.

There are few area in which the bad quality mesh is occuring.

I also look at mass flow rate at inlet and outlet and compare them. Is this the one of the way how to judge convergence?

I also try to cut the whole body to more bodies and use multizone meshing. But at the boundary between bodies was occuring mesh with low orthogonal quality.

Thanks Amine