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Why is the osilication in my solution?

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Hi,

I met a unstable numerical problem. In my 1-D model, I used "coefficient PDE" application mode in COMSOL v 3.5. there is no diffusion term appearing in my equation, only convention term. There is the model eqauion:

d(u_gas*rho_gas)/dx=S_rho_gas

the dependent variable is rho_gas, u_gas represents the constant gas velocity=0.35

I used the stationary solver. it can be solved by comsol but give the osillicated results. I try to get the reasons from the help file and found the Peclet number is infinite. It is recommented to add the artificial diffusion term.

In my case, How to add the artificial diffusion term on this equation? Is it the only method to solve the pure convection problem in COMSOL?

Thank you very much!!

0 Replies Last Post 2010年10月29日 GMT-4 13:56
COMSOL Moderator

Hello Guangji Ji

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