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Kunal Jain August 16, 2001 15:21

SIMPLE Boundary Conditions
 
If I use the staggered grids and have the half control volumes on the boundary

1.) Would I be putting in some guess values of pressure at that boundary although P correction has to be zero.

2.) Moreover if I specify the guess pressure at the boundary my normal velocity face at that surface and the press. node coincide. Should that be a problem.

Do higher Reynolds number (>500) pose a problem if I have a pure iterative scheme (Gauss -Siedel) of solving the equations.

Any books as to how to treat the boundaries except for Patankar and Peric as I am not too sure how to specify the velocities and pressure at the boundaries. Thanks in advance.

Sebastien Perron August 17, 2001 08:20

Re: SIMPLE Boundary Conditions
 
Usual BC for incompressible flow:

1) Normal velocity imposed (such as on a wall or at an inlet) : derivative of the correction of pressure will be such that the final velocity will agree with the normal velocity (neumann BC for correction of pressure)

2) Pressure imposed: Dirichlet BC for pressure correction. Neumann BC for velocity (usually zero at an outlet).

Mukhopadhyay August 19, 2001 22:57

Re: SIMPLE Boundary Conditions
 
Kunal, Is the question like this: "I use SIMPLE with staggerred grid. What are the bc's for momentum equations? What are the bcs for the p' eqn? Are they compatible, even if I use the half cvs (Patankar's approach 'B')?"

Kunal Jain August 20, 2001 09:58

Re: SIMPLE Boundary Conditions
 
Mukhopadhyay, Pretty much. And I am not too sure as to how to implement these conditions on the grid. Like how should I be constructing my grid.



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