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Convergence

hi,
I have a question...
how can I converge an equation with just a convection term?
I don't have any diffusion and unsteady and source terms...
does it have any specific discretization? :(

 laingmj January 8, 2014 09:27

More detail

Can you describe in more detail what it is that you are trying to do?

Quote:
 Originally Posted by laingmj (Post 469138) Can you describe in more detail what it is that you are trying to do?
I use a finite volume code, in the species equation with the simplification I just have a convection term and it is equal to zero.
In this situation my code is running to diverge.

 FMDenaro January 8, 2014 12:49

Quote:
 Originally Posted by amirmohammad (Post 469157) I use a finite volume code, in the species equation with the simplification I just have a convection term and it is equal to zero. In this situation my code is running to diverge.

Is that something like Div (rho*V) =0 ? that is a constraint, must be satisfied coupling it to the other equations.

Quote:
 Originally Posted by FMDenaro (Post 469162) Is that something like Div (rho*V) =0 ? that is a constraint, must be satisfied coupling it to the other equations.
It is Div (rho*U*C)=0.0

C is the concentration of species.

 FMDenaro January 8, 2014 13:02

the key is the same, the convergence of the solution is obtained while solving a system of equations, you can not focus only on this single equation

Quote:
 Originally Posted by FMDenaro (Post 469166) the key is the same, the convergence of the solution is obtained while solving a system of equations, you can not focus only on this single equation
I have 5 equations

1) u momentum
2) v momentum
3) pressure correction
4) oxygen concentration
5) water concentration

in water concentration I just have a convection term as follow:
Div ( rho*U*C) = 0.0

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