CFD Online Logo CFD Online URL
Home > Forums > Software User Forums > ANSYS > FLUENT

LES initialization

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

LinkBack Thread Tools Search this Thread Display Modes
Old   September 13, 2008, 13:59
Default LES initialization
Abdel Dehbi
Posts: n/a
Hello all,

I want to use LES for turbulent pipe flow. After initialization of the RANS field following Fluent guidelines, I switch to LES, but I always end up with laminar flow. Any clue how I could initialize the flow to reach turbulent conditions with LES? Thanks.

  Reply With Quote

Old   September 19, 2008, 08:54
Default Re: LES initialization
Paolo Lampitella
Posts: n/a
I'm simulating the turbulent channel flow and i used the logistic map:

/************************************************** ******************** UDF for initialize the field with the logistic map ************************************************** ********************/

#include "udf.h"



cell_t c;

Thread *t;

real x[ND_ND];

real x0, y0, z0;

real pi, ck, cn;

real ax, ay, a0, ak;

pi = M_PI;

ck = 0.5;

cn = 3.891;

ax = 20.0*pi;

ay = 20.0*pi;

ak = ck;






x0 = x[0];

y0 = x[1];

z0 = x[2];

a0 = ak;

ak = cn*a0*(1-a0);

C_U(c,t) = -20.0*y0*(y0-2) + 4.0*(0.5-ak);

a0 = ak;

ak = cn*a0*(1-a0);

C_V(c,t) = 4.0*(0.5-ak);

a0 = ak;

ak = cn*a0*(1-a0);

C_W(c,t) = 4.0*(0.5-ak);





and it seems to work properly. Some stuff in the UDF is not used but it should work
  Reply With Quote


Thread Tools Search this Thread
Search this Thread:

Advanced Search
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 Off
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
initialization kunal FLUENT 5 April 17, 2008 23:45
Initialization - VOF moas FLUENT 4 February 19, 2008 23:35
DPM Initialization Johannes FLUENT 1 June 20, 2007 10:27
initialization alfa FLUENT 0 March 19, 2006 11:26
Initialization of VOF Jennie Main CFD Forum 4 November 18, 1999 17:41

All times are GMT -4. The time now is 00:37.