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-   -   How to deal with the nonlinear convective term? (http://www.cfd-online.com/Forums/main/4188-how-deal-nonlinear-convective-term.html)

D.Yang December 6, 2001 10:10

How to deal with the nonlinear convective term?
 
I am a novice. I try to solve primitive variable Navier-Stokes Equation using projection method in combination with multigrid. Without introducing turbulence model. I doní»t know how to deal with the nonlinear convective term of the momentum equation before iteration. Who can help me? Thanks. David Yang

Junseok Kim December 8, 2001 14:41

Re: How to deal with the nonlinear convective term
 
Usually people use it as a source term, so by using Taylor expansion and high order Godnov upwind method, you can get, convection term at time n+1/2.


kenn January 16, 2002 17:24

Re: How to deal with the nonlinear convective term
 
on introductory level of CFD, nonlinearity is nothing.

in FDM, one simple idea to deal with nonlinear terms in time dependent problem: for example, f(u) du/dx, treat f(u) as something known at time n+1, which can be calculated from data at time n; du/dx is discretized at time n+1.

but, later on, you'll find out it's nonlinearity that causes CFD much harder than computational solid mechanics.



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