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ganesh September 9, 2008 16:17

Reimann problems
 
Dear Friends,

I have two queries.

1. When a 1-D reimann problem is cast as 2D, making the v-velocity component zero, and the problem involves a single shock, Quirk reports the odd-even decoupling problem, leading to numerical disturbances behind the shock. Is this observed for a single rarefaction wave also ? In other words, do genuinely non-linear fields experience this problem when cast in 2D?

2. I have seen several computations of Reimann problems, but not with Roe Reimann solver. Is it that the 2D problem, is four initial 1-D reiamnn problems and decoupling issues with Reimann solvers prevent their usage ?

Thanks in advance Regards,

Ganesh

Brian September 9, 2008 17:17

Re: Reimann problems
 
Actually I have a question for you.

How can I move from 1-D Riemann problem to 2-D. In other words, where to start in order to move to 2-D and 3-D. As I understand it there is no 2-D or 3-D Riemann problem and the problem am still a beginner.

Thanks.


Perumal September 10, 2008 01:42

Re: Reimann problems *NM*
 

ganesh September 10, 2008 02:08

Re: Reimann problems
 
Dear Brian,

The easiest way is to take a 1D problem, and consider it in a 2D domain, with the same states as in 1D, with the v-velocity component zero. There are otherwise 2D reimann problems, where analogous to 1D where left and right states are defined, initial states are defined on four quadrants. 26 such cases exist and a good review of these using central schemes can be found in the paper of Kurganov&Tadmor, among others.

Hope this helps.

Regards,

Ganesh

exporting October 6, 2008 17:51

Re: Reimann problems
 
is it reimann or riemann?

Nishu July 7, 2009 13:29

Ganesh,

Did you solve the riemann problem for 1 D? Are you dealing with compressible flow?
Were you able to figure it out? Reply me at babuu.nishu@gmail.com
Thanks


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