CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Fluent UDF and Scheme Programming

frictional flow

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

Reply
 
LinkBack Thread Tools Display Modes
Old   January 24, 2013, 02:41
Default frictional flow
  #1
New Member
 
virendra kumar
Join Date: Jan 2013
Posts: 5
Rep Power: 4
viru4u06 is on a distinguished road
Dear, I am working on frictional flow through diffuser. I have analytically derived all. I have compressible flow(air) and defined locally Reynold no. viscosity, velocity, and fanning frictional coefficient etc. at each .5mm along the diffuser. I want to define variable frictional coefficient across the diffuser. If possible please help me.

Thanks
viru4u06 is offline   Reply With Quote

Old   January 24, 2013, 02:49
Default variable friction factor
  #2
New Member
 
virendra kumar
Join Date: Jan 2013
Posts: 5
Rep Power: 4
viru4u06 is on a distinguished road
Dear all
I want to define variable friction factor across the duct.
Please help me
viru4u06 is offline   Reply With Quote

Old   February 14, 2013, 18:22
Default
  #3
New Member
 
Jing
Join Date: Feb 2013
Posts: 13
Rep Power: 4
serene6390 is on a distinguished road
Hi, I wish I could answer your problem, I'm also doing frictional flow analysis with various area duct. I'm confused how did you define the frictional coefficient?

Thanks a lot!
maybe we can discuss about our model later on.
serene6390 is offline   Reply With Quote

Old   February 15, 2013, 00:42
Default frictional coefficient
  #4
New Member
 
virendra kumar
Join Date: Jan 2013
Posts: 5
Rep Power: 4
viru4u06 is on a distinguished road
By using Fanning friction factor, Darcy, and Swami Jain equation i defined the friction factor in terms of Fanning friction coefficient. i.e,
f=0.0625/(log10((K/3.7*Dh)+(5.74/Re^0.9)))^2
where K= wall roughness
Dh=hydraulic dia.
Re=Reynold no.=(rho*V*Dh)/mu
mu= Sutherland viscosity= C1T^1.5/(T+C2)
where C1=1.7165*10^-5, C2= 273.11

Quote:
Originally Posted by serene6390 View Post
Hi, I wish I could answer your problem, I'm also doing frictional flow analysis with various area duct. I'm confused how did you define the frictional coefficient?

Thanks a lot!
maybe we can discuss about our model later on.
viru4u06 is offline   Reply With Quote

Old   February 15, 2013, 01:09
Default
  #5
New Member
 
Jing
Join Date: Feb 2013
Posts: 13
Rep Power: 4
serene6390 is on a distinguished road
Thanks a lot for your explaination, but how did you set the friction factor in Fluent? I know your problem is how to set the various friction factor which unfortunately I've no idea, but I'm wondering how did you set the friction factor if it is just constant? in the wall boundary condition?
serene6390 is offline   Reply With Quote

Old   February 15, 2013, 07:21
Default frictional coefficient
  #6
New Member
 
virendra kumar
Join Date: Jan 2013
Posts: 5
Rep Power: 4
viru4u06 is on a distinguished road
Hi, I am also looking same thing. I don't know how to define friction factor in fluent.


Quote:
Originally Posted by serene6390 View Post
Thanks a lot for your explaination, but how did you set the friction factor in Fluent? I know your problem is how to set the various friction factor which unfortunately I've no idea, but I'm wondering how did you set the friction factor if it is just constant? in the wall boundary condition?
viru4u06 is offline   Reply With Quote

Reply

Tags
friction factor

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
Different flow patterns in CFX and Fluent avi@lpsc FLUENT 4 April 8, 2012 06:12
Flow meter Design CD adapco Group Marketing CD-adapco 3 June 21, 2011 08:33
mass flow in is not equal to mass flow out saii CFX 2 September 18, 2009 08:07
potential flow vs. Euler flow curious ... Main CFD Forum 23 July 21, 2006 07:40
Plug Flow Franck Main CFD Forum 3 September 4, 2003 05:57


All times are GMT -4. The time now is 00:22.