CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Main CFD Forum

negative pressure & ideal gas equation invalid

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

Reply
 
LinkBack Thread Tools Display Modes
Old   August 21, 2013, 01:11
Default negative pressure & ideal gas equation invalid
  #1
New Member
 
Vignesh
Join Date: Jan 2011
Posts: 4
Rep Power: 5
Vicky88 is on a distinguished road
hi all,
i am currently working on an in-cylinder cold flow problem where i am trying to simulate the mesh motion. i am simulating the case only for a 1/8th sector of the chamber. i have 740k elements where its bfc in the moving region and tets in the rigid regions. i initialised the problem with gauge pressure 295725 Pa and reference pressure 0 Pa. the temperature was 407.811 K. while i simulate and plot the static pressure, the values become negative after a few iterations. i tried plotting the temperature, density and pressure to check the validity of the ideal gas equation. when i try to calculate pressure/(density*temperature), its not constant for all time-steps.. need some expert advice on why the ideal gas equation is not followed..
Vicky88 is offline   Reply With Quote

Reply

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
Modeling transient negative pressure (suction pressure) in outlet N_mrtz FLUENT 1 July 18, 2013 20:59
channelFoam for a 3D pipe AlmostSurelyRob OpenFOAM 3 June 24, 2011 13:06
BlockMesh FOAM warning gaottino OpenFOAM Native Meshers: blockMesh 7 July 19, 2010 14:11
Gas pressure question Dan Moskal Main CFD Forum 0 October 24, 2002 22:02
Hydrostatic pressure in 2-phase flow modeling (long) DS & HB Main CFD Forum 0 January 8, 2000 15:00


All times are GMT -4. The time now is 03:10.