Help with pimpleFoam

fcortes · February 8, 2011, 06:37

Hello everyone,

I’m using pimpleFoam to simulate a 3D flow on a very small irregular tube (total volume around 2e-7; 150000 elements (tetrahedral)). I’ve used the files of T-junction tutorial as a base. I’m also using GroovyBC to make the pulsatile velocity with a parabolic profile at the inlet and the pressure at the outlet. Turbulence model is a RAS kOmega and the fluid is Newtonian.

I’ve achieved convergence with pulses with top inlet velocity around 0.6 (Re=450). The minimum time step then was 1.8e-5. The problem is that I can’t achieve convergence with higher inlet velocities (Re=650 to 800). I’ve tried a lot of combinations of correctors (1 to 4), nonOrthogonalCorrectors (1 to 4), outerCorrectos (1 to 4), maxCo (1 to 0.5) and relaxation factors (1 to 0.05). I always get a blowout close to the top velocity but sometimes at a velocity lower than the top velocity of the case that worked, which to me is very weird.

If someone knows what I can do to solve this (or needs more info to do so) please let me know.
Thanks in advance!

Francisco

1988 · June 26, 2014, 09:46

Hello Fransisco
I have ctuck in a problem the same as yours ,did you find an answer?
please help me tanks

fcortes · June 26, 2014, 11:31

Nop, I ended up simulating those cases in fluent.
Good luck!

February 8, 2011, 06:37	Help with pimpleFoam	#1
fcortes New Member Francisco Cortés Join Date: Sep 2010 Location: Santiago, Chile Posts: 7 Rep Power: 15	Hello everyone, I’m using pimpleFoam to simulate a 3D flow on a very small irregular tube (total volume around 2e-7; 150000 elements (tetrahedral)). I’ve used the files of T-junction tutorial as a base. I’m also using GroovyBC to make the pulsatile velocity with a parabolic profile at the inlet and the pressure at the outlet. Turbulence model is a RAS kOmega and the fluid is Newtonian. I’ve achieved convergence with pulses with top inlet velocity around 0.6 (Re=450). The minimum time step then was 1.8e-5. The problem is that I can’t achieve convergence with higher inlet velocities (Re=650 to 800). I’ve tried a lot of combinations of correctors (1 to 4), nonOrthogonalCorrectors (1 to 4), outerCorrectos (1 to 4), maxCo (1 to 0.5) and relaxation factors (1 to 0.05). I always get a blowout close to the top velocity but sometimes at a velocity lower than the top velocity of the case that worked, which to me is very weird. If someone knows what I can do to solve this (or needs more info to do so) please let me know. Thanks in advance! Francisco

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Running stably with a large Courant number using pimpleFoam	mlawson	OpenFOAM	11	November 29, 2014 10:37
Restarting with pimpleFoam	deinstein	OpenFOAM	9	November 27, 2013 08:53
Problem running IDDES with pimpleFoam	charlie	OpenFOAM Running, Solving & CFD	7	July 11, 2013 11:45
tried with pimpleFoam and a big CFL = 5	ivan_cozza	OpenFOAM Running, Solving & CFD	9	June 4, 2013 18:14
PimpleFoam problem	Vadims.geza	OpenFOAM	8	December 7, 2011 08:54

June 26, 2014, 09:46		#2
1988 Senior Member Ali reza Join Date: Mar 2014 Posts: 110 Rep Power: 12	Hello Fransisco I have ctuck in a problem the same as yours ,did you find an answer? please help me tanks

June 26, 2014, 11:31		#3
fcortes New Member Francisco Cortés Join Date: Sep 2010 Location: Santiago, Chile Posts: 7 Rep Power: 15	Nop, I ended up simulating those cases in fluent. Good luck!