pressure coorection

rr_amerian · August 3, 2009, 02:59

Hello all,

I am a PhD student, writing a CFD code for a laminar flow in cylindrical axisymetric coordinate. I can not converge my code

and I think the problem is in exerting boundary conditions of pressure correction equation.

I will be so thankful if anybody can send me the boundary conditions of Pressure correction equation in SIMPLE algorithm.

Thanks everybody.
Good Luck

m.iran · August 20, 2009, 05:54

Normaly there are 2 kinds of conditions at boundary, either the pressure at boundary is given and normal velocity is unknown or vice versa.
1.Given pressure : if guessed pressure field is arranged such that at boundary P*= Pgiven, then value of the P' at the boundary will be zero.
2.Given normal velocity: for example if the velocity has be given just at western face, just the coefficient of aw at pressure correction Eq will be zero, and other coefficients don't change. and u* at west shouldn't be corrected. (because it is given as boundary condition and does not change)

it is illustrated in Numerical heat transfer and fluid flow by patankar.

SKK · August 20, 2009, 06:41

Have a look at the book 'An introduction to computational fluid dynamics, the finite volume method' by H. K. Versteeg & W. Malalasekera.

August 3, 2009, 02:59	pressure coorection	#1
rr_amerian New Member rosa amerian Join Date: Aug 2009 Posts: 1 Rep Power: 0	Hello all, I am a PhD student, writing a CFD code for a laminar flow in cylindrical axisymetric coordinate. I can not converge my code and I think the problem is in exerting boundary conditions of pressure correction equation. I will be so thankful if anybody can send me the boundary conditions of Pressure correction equation in SIMPLE algorithm. Thanks everybody. Good Luck

August 20, 2009, 05:54	RE. Pressure correction equation in SIMPLE algorithm	#2
m.iran New Member Mohammad Haddadi Join Date: Aug 2009 Location: Tehran,Iran Posts: 4 Rep Power: 0	Normaly there are 2 kinds of conditions at boundary, either the pressure at boundary is given and normal velocity is unknown or vice versa. 1.Given pressure : if guessed pressure field is arranged such that at boundary P= Pgiven, then value of the P' at the boundary will be zero. 2.Given normal velocity:* for example if the velocity has be given just at western face, just the coefficient of aw at pressure correction Eq will be zero, and other coefficients don't change. and u* at west shouldn't be corrected. (because it is given as boundary condition and does not change) it is illustrated in Numerical heat transfer and fluid flow by patankar.

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August 20, 2009, 06:41		#3
SKK Member Join Date: Mar 2009 Posts: 55 Rep Power: 17	Have a look at the book 'An introduction to computational fluid dynamics, the finite volume method' by H. K. Versteeg & W. Malalasekera.