CFD Online Discussion Forums

CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   Main CFD Forum (http://www.cfd-online.com/Forums/main/)
-   -   2d supersonic flow over flat plate (http://www.cfd-online.com/Forums/main/7276-2d-supersonic-flow-over-flat-plate.html)

puzzled March 10, 2004 22:47

2d supersonic flow over flat plate
 
Does anybody know the reason why the solution starts to blow up over Ma 9 during iteration ?

I am using time marching Mac Cormack method and changed only free stream velocity as Ma increases.

It was possible to get stable solution by decreasing time step arbitrarily but there existed the limit.

At Ma 25 , the target, the solution blew up however small I set up the time step.

Have a good day, you all.

versi March 11, 2004 22:53

Re: 2d supersonic flow over flat plate
 
flow variables jump more as Ma increase. If your numerical scheme rely on numerical viscosity to smooth this jump, it means needing larger viscosity.

puzzled March 17, 2004 19:07

Re: 2d supersonic flow over flat plate
 
Thanks a lot, versi~ :D


All times are GMT -4. The time now is 06:59.