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

Recommended values on turbulence B.C.

Register Blogs Community New Posts Updated Threads Search

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   August 9, 2005, 01:48
Default Recommended values on turbulence B.C.
  #1
Jihwan
Guest
 
Posts: n/a
Hi there,

I am not good at turbulence. But, as you know, it is very important to consider turbulence for the flow in complicated geometries. What I want to know is that whether there are good recommendations for the turbulence boundary conditions. Of course, the turbulence B.C. should depend on flow pass and environments. I hope to get any literature concerning recommended turbulence boundary conditions for various flow conditions and geometry. Thanks in advance and good luck everybody

Jihwan
  Reply With Quote

Old   August 10, 2005, 04:53
Default Re: Recommended values on turbulence B.C.
  #2
AlexMuthaiah
Guest
 
Posts: n/a
Hi, Turbulence Boundary condition in the sense u need to maintain a suitable Y+ values around the wall region and which inturn depend on ur tubulence models which u r going to use. For each TModels appropriate closure coefficients u need to use usually software will take care by using its default values.

U need to check for gridsenstivity.

regards'

Alex
  Reply With Quote

Old   August 10, 2005, 08:45
Default Re: Recommended values on turbulence B.C.
  #3
allan
Guest
 
Posts: n/a
Hi

If you are considering inlet boundaries then you could try setting turbulence intensity to say 2%, running the model then double it and run the model again and so on until there isn't any appreciable difference in the turbulent flow field.

For internal flows length scale can be set to 10% of the hydraulic diameter of the duct.

Y+ is also very important, but if you choose hybrid wall functions then it becomes less of an issue.

allan

  Reply With Quote

Reply


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
turbulence values nando FLUENT 0 December 12, 2005 04:45
values for turbulence models Ben Siemens 8 July 12, 2004 14:42
Help - Wind Turbulence Values Erich Main CFD Forum 0 November 11, 2003 19:32
Turbulence boundary values lego CFX 9 October 25, 2002 12:55
Turbulence boundary values lego Main CFD Forum 0 October 24, 2002 14:47


All times are GMT -4. The time now is 10:33.