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vivian June 21, 2006 00:43

implicit scheme for time step
 
Hi,everyone,

I want to use high-order implicit scheme for time step. Which kinds of scheme should I choose for shock capturing?

Thanks!

vivian

ztdep June 21, 2006 12:01

Re: implicit scheme for time step
 
I thint to chature the shock, one need a high resolution space shemem! am i right!

vivian June 21, 2006 21:38

Re: implicit scheme for time step
 
Thank for your reply!

Yes!I think using the high-scheme for space is important. Do you think the high-scheme for time is also important or less important than high-scheme for space or can be ignored for shock capturing?

vivian

khai ching June 22, 2006 01:27

Re: implicit scheme for time step
 
It depends on the time nature of your problem. If you are concerning about steady-state solution, high-order scheme for time is less important and you should devise a time-marching scheme which can result in rapid convergence(good damping property). For real transient case, of course, higher-order scheme is attractive in terms of resolving the unsteadiness.

For shock-capturing purpose, I presume that spatial differencing scheme plays a very important role. It is crucial not only in the subject of numerical accuracy(high-order scheme) in order to allow us to resolve the shock wave sharply, the scheme must be bounded in the sense of it won't create spurious oscillations in region near the flow discontinuity, which is always the main issue of the implementation of high-order scheme.

-khai ching-

vivian June 23, 2006 03:47

Re: implicit scheme for time step
 
Thank you for your reading!

I found the resonant oscillation in my tube was not stable under the resonant frequency.It is not agree well with the literature. Is it the reason of scheme of time or other reasons?

vivian


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