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

[Q] Steady Compressible High Reynolds Problem.

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   March 2, 2000, 21:23
Default [Q] Steady Compressible High Reynolds Problem.
  #1
Ryu, Sung Min
Guest
 
Posts: n/a
Problem : Steady Inviscid Compressible Model : NACA0012 2D airfoil(Chord length = 1) Conditions : Reynolds Number = 8.e6, Mach Number = 0.76, angle of attack= 1.43 degree Mesh : 164 X 84 O-type Grid

Under above conditions, Shock is seen at 0.4 chord length on upper surface by experiment results and other numerical results. But I can't see the same result by STAR-CD. I see the shock at 0.95 chord length. I wonder that STAR-CD can solve exactly the high Reynolds number problems like this.

Questions: 1. Is there any other boundary condition available in STAR-CD to describe Subsonic Freestream condition ? (I used Inlet Boundary condition) 2. Can STAR-CD capture the shock exactly? 3. The mesh used is very dense near airfoil surfaces. The smallest mesh size is of order 1.e-5. Is it OK in STAR-CD ?
  Reply With Quote

Old   March 27, 2000, 15:55
Default Re: [Q] Steady Compressible High Reynolds Problem.
  #2
Dean Hawkinson
Guest
 
Posts: n/a
I am running a very similar case. I also used inlet b.c. I've had the same problem but tightening the convergence criteria seemed to help. Unfortunately, I've been seeing a lot of smearing of the shock. Suggestions would be welcome.

Good Luck

Dean
  Reply With Quote

Old   March 31, 2000, 12:46
Default Re: [Q] Steady Compressible High Reynolds Problem.
  #3
John C. Chien
Guest
 
Posts: n/a
(1). The answer is very simple: ask the code vendor to provide a benchmark test result of a transonic flow over an airfoil with shock. (2). This is the only way to find out whether the code can or can not pass the validation phase. If the vendor can provide the report or paper, then you can try to repeat the test result on your own. Hopefully, at the end of your own test, you will have the answer you are looking for.
  Reply With Quote

Reply

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
SimpleFOAM for steady globally unstable Reynolds number pbohorquez OpenFOAM Running, Solving & CFD 0 February 19, 2009 10:47
Low/High Reynolds models? Ralf Schmidt Main CFD Forum 0 May 18, 2006 06:47
High Reynolds 2D Airfoil Carlos Saraiva Siemens 0 January 17, 2003 08:36
high and low reynolds numbers - what does it mean Bo Busk Jensen Main CFD Forum 3 September 5, 2002 05:41
"The high Reynolds number flow is not difficult to compute, the problem is we simply don't know how. wowakai Main CFD Forum 1 November 11, 1998 10:24


All times are GMT -4. The time now is 03:56.