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

porou jump, permeability

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

Reply
 
LinkBack Thread Tools Display Modes
Old   July 9, 2010, 09:33
Default porou jump, permeability
  #1
New Member
 
Join Date: Jul 2009
Posts: 8
Rep Power: 8
pertupd is on a distinguished road
Hy all,
I trying to set porous jump model in fluent to model 3D flow over perforated plate (cca, 10 mm in thickness).
I computed inertial resistance and face permeability according to fluent 6.3 User guide 7.19.6 paragraph based on tabulated values of delta pressure - velocity (dp-c) dependence. The dp-c was determined based on detail fluid flow over element of the perforated plate.
I approximated dp-c dependence by quadratic equation:
dp=a*c^2 + b*c
But the b coefficient is negative for my case and thus the permeability value (alfa) too.
Problem is that fluent does not accept negative value of alfa.
How to input the alfa?
if I thing that the model with dp=.. -b*c is different to the dp=.. +b*c.

By the way the value of alfa is rather small (of order of 1.e-7) - thus enhancing einfluence of inertial resistance.
Order of C2 (inertial resistance coefficient) is cca 500 for the plate.

Thanks.
pertupd is offline   Reply With Quote

Old   April 15, 2014, 23:52
Default
  #2
New Member
 
Join Date: Apr 2014
Posts: 28
Rep Power: 3
will321321 is on a distinguished road
Hello,

I am Having the same problem with the same procedure can someone please enlighten us.

thank you.
will321321 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
UDF: DEFINE_CG_MOTION for vertical jump motion of an electrode! alban Fluent UDF and Scheme Programming 2 June 8, 2010 18:54
Pressure jump and momentum source Tanya FLUENT 1 June 4, 2009 15:22
Porous Jump Naresh FLUENT 0 April 25, 2007 15:36
correct assignment of permeability? jemteo CFX 0 March 17, 2006 06:34
Please Help ! Pressure Jump of Fan?? Boris FLUENT 0 January 28, 2003 21:26


All times are GMT -4. The time now is 18:21.