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 YeChen April 14, 2012 09:44

some puzzles on Boundary condition transformation

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Hello,everyone. I want to simulate a supersonic (Ma=4.0) flow fleid around a circular body and check for the shock/boundary profiles. I choose to use the finite difference method(FDM),and hence I do a grid transformation from physical domain(x,y) to computational domain(ξ,η). And there comes some puzzles:
Attachment 12550
1) on the physical outflow boundary the condition like ux(imax,j)=ux(imax-1,j) such interpolations, how to convert this to the computational domain ?

2) what scheme is suitable for super/hypersonic problems like this, MacCormack seems have strong oscilations around the shock. what about Ausm series?

3) During the grid transformation, is second-order estimation of Jacobians like Xξ sufficient?

Thank you very much for advises, my friends. I am looking forward for your help. :)

 SergeAS April 14, 2012 10:59

Quote:
 Originally Posted by YeChen (Post 354689) 2) what scheme is suitable for super/hypersonic problems like this, MacCormack seems have strong oscilations around the shock. what about Ausm series?
In your case you need one of shock-capturing schemes http://en.wikipedia.org/wiki/Shock_capturing_methods

 YeChen April 15, 2012 09:00

Quote:
 Originally Posted by SergeAS (Post 354697) In your case you need one of shock-capturing schemes http://en.wikipedia.org/wiki/Shock_capturing_methods