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

How much do I numerical dissipation?

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

Reply
 
LinkBack Thread Tools Display Modes
Old   February 23, 2004, 01:02
Default How much do I numerical dissipation?
  #1
QU KUN
Guest
 
Posts: n/a
I'm studying a kind of particle method in which viscosity can be controled quantificationally. I'm trying to solve shockwave case with it. Because of the dicontinuity, some numerical disipation is needed. I tried to add an additional viscosity term. But I don't know how to define the viscosity coeeficient of the numerical disipation.

  Reply With Quote

Old   February 23, 2004, 02:30
Default Re: How much do I numerical dissipation?
  #2
Apurva
Guest
 
Posts: n/a
which scheme r u using
  Reply With Quote

Old   February 23, 2004, 04:46
Default Re: How much do I numerical dissipation?
  #3
QU KUN
Guest
 
Posts: n/a
The scheme is not of FDM/FVM/FEM. It is a kind of lattice boltzmann scheme in which viscosity can be controlled by a parameter Tao. At every node, the viscosity nu is a function of pressure P and collision time Tao. If the viscosity is known, I can get Tao according to P. Now I don't know how to estimate the best viscosity nu. If nu is too small, Tao will be too small and the solver will diverge. If it is too large, Tao will be too large and the result will be absurd.
  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
Test Case for testing numerical dissipation Flo Main CFD Forum 6 January 25, 2008 13:35
how to quantify numerical dissipation Márcio Ricardo Main CFD Forum 15 November 9, 2005 21:15
numerical dissipation zwdi FLUENT 2 June 3, 2004 21:09
Kinetic schemes and numerical dissipation Praveen Main CFD Forum 0 September 6, 2002 07:09
Numerical Dissipation sam Main CFD Forum 0 June 22, 2002 19:14


All times are GMT -4. The time now is 03:24.