|
[Sponsors] |
![]() |
![]() |
#1 |
New Member
Stephen Waite
Join Date: May 2013
Location: Auckland, New Zealand
Posts: 29
Rep Power: 12 ![]() |
Hi everybody.
I need a bit of help with boundary conditions. I am performing a 1-way fsi in fluent. I have a balloon-like structure that contracts, expelling fluid out of an opening. This balloon then expands, drawing fluid back into the balloon through the same opening. I am currently modelling this opening as a pressure-outlet boundary condition. My model is converged but at the transition between contraction and expansion there is a discontinuity in the flow and pressure fields (i am assuming that the discontinuity in the flow is produced because of the pressure discontinuity). I do not really understand how the pressure-outlet works I assumed it just set a 0 gauge pressure at the boundary and so was effectively and 'opening' condition like what is offered in CFX. Does the pressure-outlet boundary have difficulty with revered flow? Can anyone think of a boundary condition that would be better for my model? I wanted to try pressure far-field but the option does not seems to be there. Any help is greatly appreciated. I am using a coupled solver scheme, PRESTO! for the pressure interpolation and a second order upwind scheme for momentum. Cheers Stephen Waite |
|
![]() |
![]() |
![]() |
|
|
![]() |
||||
Thread | Thread Starter | Forum | Replies | Last Post |
mass flow in is not equal to mass flow out | saii | CFX | 12 | March 19, 2018 05:21 |
Implementation of boundary conditions for FVM | Tom | Main CFD Forum | 7 | August 26, 2014 05:58 |
Question about heat transfer coefficient setting for CFX | Anna Tian | CFX | 1 | June 16, 2013 06:28 |
CFX13 Post Periodic interface | EtaEta | CFX | 7 | December 8, 2011 17:15 |