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tang September 18, 2003 15:37

Trouble in solving stiff eq
 
I have a system consisting of 2 PDE (resulting from continuity and momentum equations). The system has very large coefficients. The system seems to be stiff since the numerical solution changes with time step and spacing (very small time step requied for stability). It seems that to be difficult to get a solution independent of mesh size and time step.

It is highly appreciated if you let me know as you have the experience to deal with such system or know some good references.

T


Greg Perkins September 18, 2003 22:31

Re: Trouble in solving stiff eq
 
Have a look for VODE and CVODE on the internat - hese are two codes for solving stiff ODE systems in Fortran and C produced at the LLNL. You should be able to download them and use them for free.

Greg

tang September 19, 2003 08:58

ODE for PDE?
 
Thanks to Perkins. But is the code for ODE good for PDE?

T



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