CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > ANSYS > FLUENT

Strange oscillatory pressure in periodic incompressible flow

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   February 6, 2018, 19:03
Default Strange oscillatory pressure in periodic incompressible flow
  #1
New Member
 
Join Date: Aug 2015
Posts: 13
Rep Power: 11
EmiS is on a distinguished road
Hello,

I'm trying to simulate a turbulent flow in a pipe-like geometry. The inlet boundary condition is periodic (velocity imposed) and the outlet BC is set to zero pressure. The pipe has sort of a ring/narrow section in the middle and among other things, I'm trying to plot the pressure difference between pressure values after and before the narrow part. I chose two cross-sections, averaged pressure in each of them and then took the difference. The result is the blue curve in the attached plot. Unfortunately, the pressure is quite oscillatory when the simulation is near inlet velocity peak and I don't manage to fix it. I tried to switch from second-order pressure to 'linear' and also to 'standard', but both only made the results look worse. Playing with relaxation parameters for pressure has some effect, but not sufficient for me to get a nicely looking result. Could you please advise what else could I change in the settings of the solver to remove the oscillations?

Thank you very much.

EmiS
EmiS is offline   Reply With Quote

Reply

Tags
periodic bc, pressure oscillation, pressure scheme, under-relaxation factor


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Specify mass flow rate for periodic boundary conditions in channel flow lion1990 OpenFOAM Running, Solving & CFD 1 July 9, 2018 18:46
BC for Actuator Disk - Flow Vel from High Pressure to Low Pressure vinguva OpenFOAM Running, Solving & CFD 2 March 8, 2016 00:46
flow simulation across a small fan jane luo Main CFD Forum 15 April 12, 2004 18:49
Hydrostatic pressure in 2-phase flow modeling (CFX4.2) HB &DS CFX 0 January 9, 2000 14:19
incompressible flow - prescribing pressure drop - how best to do it? M. Gerritsen Main CFD Forum 4 January 10, 1999 10:53


All times are GMT -4. The time now is 17:57.