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The coefficient value for neighbouring cells

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Old   December 18, 2005, 16:17
Default Hi, The resulting algebraic
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olivier Petit
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Hi,
The resulting algebraic equation for a general variable (phi) linking its value at the center of a control volume P with the values of neighbouring cells (n) are:

A_p *Phi_p=Sum_n(A_n * Phi_n ) + S_(phi)
with :
A_p=Sum_n(A_n)+ S_p

My question is:
How can I get the coefficient A_n ?
thanks for your help.
best regards
olivier
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Old   December 18, 2005, 16:26
Default Have a look at lduMatrix.H - t
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Hrvoje Jasak
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Have a look at lduMatrix.H - the member function you want is called diag()

Enjoy,

Hrv
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Old   December 18, 2005, 19:52
Default HI Jasak, I have some confu
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olivier Petit
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HI Jasak,
I have some confusion:
I think that Ap is calculated in O.FOAM as:
Ap=diag()/mesh.V();
and you said that A_n=diag()
but in the theory Ap=Sum_n(A_n)+ S_p;
how come ?
thanks for your help.

olivier
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