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

how to calculate CFL number in 3D convection-diffusion channel flow

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

Reply
 
LinkBack Thread Tools Display Modes
Old   June 24, 2009, 03:33
Default how to calculate CFL number in 3D convection-diffusion channel flow
  #1
New Member
 
Li.cy
Join Date: May 2009
Posts: 3
Rep Power: 8
dryhill is on a distinguished road
1. 3D channel flow , equation is
df/dt + c df/dx = nu*d^2f/dx^2
unsteady channel flow

2. spacial discretization is second CDS, time discretization is implicit Euler.

3. in x,y,z direction, length of FVM is dx,dy,dz respectively,

how to calculate CFL number in 3D case?

in peric's book , it was mentioned :
dt < 1/(2*nu/dx**2 + c/dx)
but it was 1D case, in channel flow, x direction is convective dorminated,
while in y direction(normal to wall), grid is fine, diffusion may be important.

welcome any reply
dryhill 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
Turbulence model for low Reynolds number flow? Nokadu Main CFD Forum 3 May 26, 2013 11:42
heat conduction in solid and convection in flow kunal FLUENT 3 February 29, 2012 05:42
CFL number specification sonic/supersonic flow gr Main CFD Forum 0 January 16, 2009 12:14
pressure outlet (open channel flow) Willem Brantegem FLUENT 2 April 4, 2007 02:40
compressible channel flow.. R.D.Prabhu Main CFD Forum 0 July 17, 1998 17:23


All times are GMT -4. The time now is 06:36.