CFD Online Discussion Forums

CFD Online Discussion Forums (
-   Phoenics (
-   -   Re: supersonic free jet nonphysical solution?? (

Patti October 23, 2008 21:12

Re: supersonic free jet nonphysical solution??
I had a problem with the underexpanded free jet in the Case Library - I believe it's case 911. This gives the correct shock structure in 2-dimensions. When I change this into a three dimensional case (by adding circumferential grid points), and change all the objects (inlets, outlets, inits) to 3-D, it begins to experience very strong inflows at points next to the axis at the outlet. I tried: - dramatically increasing relaxations - decreasing the "snap" distance setting on the grid (maybe some of the points were degenerate?) - increasing the "coefficient" setting of the inlet

I don't know what else to try. I have occasionally experienced nonphysical behavior in cylindrical coordinates before and wonder if that's a hazard from the convergence of circumferential points near the axis, or if it's a problem with the solver? Thank You!!!!!!!!!!!!

All times are GMT -4. The time now is 20:48.