CFD Online Logo CFD Online URL
Home > Forums > FLUENT

Mass Increase for closed system with moving wall

Register Blogs Members List Search Today's Posts Mark Forums Read

LinkBack Thread Tools Display Modes
Old   January 21, 2009, 16:00
Default Mass Increase for closed system with moving wall
Posts: n/a
My issue is with a closed system filled with an ideal gas. It is a 2D axisymmetric model which also includes a moving wall representing a pressure wave generator or piston-cylinder assembly. The problem is the system's mass is steadily increasing. I have tried several variations on modeling the moving wall using various smoothing techniques. I am certain the moving mesh and its UDF is working properly with visual reference, however I believe the code is somehow adding mass on the back stroke.

Any help would be greatly appreciated. Thanks.
  Reply With Quote

Old   June 8, 2012, 03:20
Question Coupled Flow _ Rigid Body Motion - Battery Cooling
New Member
Join Date: Jun 2012
Posts: 4
Rep Power: 7
simonart7 is on a distinguished road
I have the same problem.
My mass flow rate is alternating increasing up to 700%.
The Residuals seems to be ok, but Tke and Tdr pass up quick above 1.
simonart7 is offline   Reply With Quote

Old   April 21, 2015, 15:14
sanjeet Limbu
Join Date: Mar 2015
Posts: 91
Rep Power: 4
sanjeetlimbu is on a distinguished road
I am getting no pressure and temperature rise for rapid compression in fluid 2D axi-symetric acse

I have entered these values at initialisation

Problem is that I am not geting temp and pressure rise during compression stroke
Attached Images
File Type: jpg dynamic mesh compression.jpg (21.7 KB, 2 views)
File Type: jpg CFD post view for pressuree contour.jpg (27.9 KB, 3 views)
File Type: jpg operating and initial values.jpg (33.9 KB, 3 views)
File Type: jpg species model.jpg (59.1 KB, 3 views)
sanjeetlimbu is offline   Reply With Quote


Thread Tools
Display Modes

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 On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Incompressible Ideal Gaz in a closed system - Help JB FLUENT 2 August 1, 2008 04:16
Combustion in a closed System Martin Castillo FLUENT 3 June 20, 2007 21:38
Combustion in a closed System Martin Castillo FLUENT 0 June 18, 2007 22:56
Combustion in a closed system. Jim Main CFD Forum 7 December 9, 2004 14:49
closed system calculation Neil MacLeod Main CFD Forum 1 May 13, 1999 15:47

All times are GMT -4. The time now is 10:56.