
[Sponsors] 
May 12, 2013, 01:25 
SIMPLE algorithm implementation, pressure correction error

#1 
New Member
David
Join Date: Feb 2013
Posts: 15
Rep Power: 5 
I have been implementing this SIMPLE algorithm to a 2D tunnel flow. I use inlet constant velocity boundary condition and outlet constant pressure boundary condition.
I can get very good flow velocity distribution, which have the max velocity in the center and zero on both tunnel wall. The max velocity magnitude also seems reasonable. But I cannot get good pressure distribution, the pressure inside the tunnel could be high up to 7 times of boundary pressure. And the strange part is the pressure distirbution seems didn't influence the velocity momentum calculation a lot, I can still get good velocity contour. Is there some one can give me some hint about this problem, which part I should look into? Thanks. 

May 12, 2013, 22:56 
HIs problem is really like me

#2 
New Member
David
Join Date: Feb 2013
Posts: 15
Rep Power: 5 
I am also implementing versteeg's book, the pressure correction got similar problem. The velocity distribution profile, pattern are all ok, but the magnitude value, if compared with slit flow theoretical value
u(y)=(dp/dx)H^2/8Miu*(1(y/0.5H)^2) the max velocity is always 50% higher than the theoretical number, I believe the problem is at pressure correction and don't know how to solve it. 

February 8, 2014, 01:15 
Simple

#3 
New Member
hadieliasi
Join Date: Apr 2011
Posts: 10
Rep Power: 6 
Hi.
I think you may use SIMPLER Algorithm that is better than SIMPLE algorithm because in SIMPLER, the pressure equation instead of pressure correction equation is solving directly. In SIMPLE even velocity distributions is correct but the pressure may not correct and needs to more iterations. but i think 2 way to solve your problem: 1At first check your code and be sure that is correct. may be the problem is about defining reference point for pressure. 2Please check b.c and be sure that they are correct. how do you define those b.c? 2Modify your code to solve simpler algorithm. It is very easy and you should change some parts of your simple code. in patankar's book " heat transfer and fluid flow " these methods are existed. i have teach and w2d code.If you need, I can send those you. 

Tags 
pressure correction, simple algorithm 
Thread Tools  
Display Modes  


Similar Threads  
Thread  Thread Starter  Forum  Replies  Last Post 
Native ParaView Reader Bugs  tj22  OpenFOAM Paraview & paraFoam  270  January 4, 2016 12:39 
Timestep and Pressure Correction Relationship in SIMPLE  rks171  Main CFD Forum  23  May 4, 2012 01:04 
Problem running perturbUCyl  sen.1986  OpenFOAM  14  March 23, 2012 05:12 
attach/detach (valve opening/closing)  phsieh2005  OpenFOAM Running, Solving & CFD  2  March 21, 2009 06:18 
Problem with compile the setParabolicInlet  ivanyao  OpenFOAM Running, Solving & CFD  6  September 5, 2008 20:50 