LES: Pressure update multiplier for Mass Flow Rate interface model

balrog_f · May 12, 2017, 05:50

Hi guys,

I'm running a LES with a translational periodic boundary condition, for which i use a given Mass Flow Rate as interface model. The convergence looks unstable after a while and i don't know how to fix it.
There is the pressure update multiplier option in the additional interface model tab. I read about it in the CFX documentation and that you can use it if the convergence looks unstable, but I don't know how to really use it and especially how sensivtive it is. Has anybody experience with this factor or further information?

ghorrocks · May 12, 2017, 07:03

I would make sure the simulation converges when you just have simple inlets and outlets first. If that converges then put the periodic boundary back in and start adjusting the options and see how it goes. Nothing beats working these things out for yourself.

May 12, 2017, 05:50	LES: Pressure update multiplier for Mass Flow Rate interface model	#1
balrog_f Member Join Date: Apr 2017 Posts: 53 Rep Power: 9	Hi guys, I'm running a LES with a translational periodic boundary condition, for which i use a given Mass Flow Rate as interface model. The convergence looks unstable after a while and i don't know how to fix it. There is the pressure update multiplier option in the additional interface model tab. I read about it in the CFX documentation and that you can use it if the convergence looks unstable, but I don't know how to really use it and especially how sensivtive it is. Has anybody experience with this factor or further information?

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
CFD analaysis of Pelton turbine	amodpanthee	CFX	31	April 19, 2018 18:02
Modeling interface of fluid and porous, not with default setting	ftab	CFX	27	May 20, 2014 06:58
Question about heat transfer coefficient setting for CFX	Anna Tian	CFX	1	June 16, 2013 06:28
Error finding variable "THERMX"	sunilpatil	CFX	8	April 26, 2013 07:00
Hydrostatic pressure in 2-phase flow modeling (long)	DS & HB	Main CFD Forum	0	January 8, 2000 15:00

May 12, 2017, 07:03		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,703 Rep Power: 143	I would make sure the simulation converges when you just have simple inlets and outlets first. If that converges then put the periodic boundary back in and start adjusting the options and see how it goes. Nothing beats working these things out for yourself.