CFD Online Logo CFD Online URL
Home > Forums > General Forums > Main CFD Forum

How to reduce instability caused by inlet perturb?

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

LinkBack Thread Tools Search this Thread Display Modes
Old   June 2, 2006, 12:02
Default How to reduce instability caused by inlet perturb?
Posts: n/a
The artificial perturbation imposed at the inlet is the sum of three sinusoidal functions with the same frequency (1.8 randian/s and f=0.3Hz)and different phases. And it is concentrated in the shear layer, the numerical scheme I use is extended MacCormack--- a explicit time integration method. while I take a nondimensinal timestep=0.01, the result oscilates intensily at the inlet, mass density and temperature decrease to a unphysical extent. How to solve this problem, please help!
  Reply With Quote

Old   June 2, 2006, 12:21
Default Re: How to reduce instability caused by inlet pert
Posts: n/a
Without seeing your problem firsthand, I'll offer this... It seems like some sort of entry shock. Could be numeric, or physical.

Perhaps you could offer a few more insights on your model?

  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
ATTENTION! Reliability problems in CFX 5.7 Joseph CFX 14 April 20, 2010 16:45
transitional inlet boundary condition kamp CFX 1 June 21, 2006 12:08
what the result is negatif pressure at inlet chong chee nan FLUENT 0 December 29, 2001 06:13
Inlet diffuser of ramjet Mohammad Kermani Main CFD Forum 25 December 29, 2000 19:46
length scales at inlet for internal flows Anne-Marie Giroux Main CFD Forum 3 July 5, 1999 22:28

All times are GMT -4. The time now is 12:25.