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

winglet analysis

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

Reply
 
LinkBack Thread Tools Display Modes
Old   September 18, 2009, 13:56
Default winglet analysis
  #1
New Member
 
kumar
Join Date: Sep 2009
Posts: 4
Rep Power: 7
cfd_lean is on a distinguished road

I am Intended to do CFD analysis on wing with winglets using CFX. I have wind tunnel results. i need to match ,my CFD data to experimental results.

I generated a grid with Icem. I generated def file using CFX pre.

The inlet conditions , known are Dynamic Pressure and free steam mach number ans Reynolds number. I did not know the outlet conditions.

Initially i started CFD runs using Velocity magnitude as inlet and atmospheric pressure as outlet. Solution did not converged and failed after 30 iterations. Then I tried by changing outlet condition to static pressure(roughly took 0.95% inlet Ps). Here also i did not get luck. I tried with keeping opening boundary condition at the outlet. Still I did not get any luck.

Let any one can suggest me how to proceed further & what modifications I need to do for setup?
cfd_lean is offline   Reply With Quote

Old   September 18, 2009, 14:51
Default
  #2
Senior Member
 
Ahmed
Join Date: Mar 2009
Location: NY
Posts: 248
Rep Power: 9
Ahmed is on a distinguished road
Quote:
Originally Posted by cfd_lean View Post

I am Intended to do CFD analysis on wing with winglets using CFX. I have wind tunnel results. i need to match ,my CFD data to experimental results.

I generated a grid with Icem. I generated def file using CFX pre.

The inlet conditions , known are Dynamic Pressure and free steam mach number ans Reynolds number. I did not know the outlet conditions.

Initially i started CFD runs using Velocity magnitude as inlet and atmospheric pressure as outlet. Solution did not converged and failed after 30 iterations. Then I tried by changing outlet condition to static pressure(roughly took 0.95% inlet Ps). Here also i did not get luck. I tried with keeping opening boundary condition at the outlet. Still I did not get any luck.

Let any one can suggest me how to proceed further & what modifications I need to do for setup?
Nothing is known at the outlet, so you select the outlet BC as your B condition,
(gradients are equal zero).
The selection of boundary conditions is not a question of trial and error, but they have to represent the physical boundary conditions that exist in your simulation. Books on CFD will give you the physical and the mathematical meaning of each boundary condition, and if you look the Help system or manuals of the soft ware you are using you will find these definitions
Ahmed is offline   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
What exactly is a sensitivity analysis? Josh CFX 3 August 19, 2009 09:18
Fan Boundary conditions with external analysis Rob FloEFD, FloWorks & FloTHERM 1 February 10, 2009 01:04
FSI Transient Thermal Analysis Abduri CFX 0 December 8, 2008 21:00
Questions on Analysis Controls and Runtime Control Arnab CD-adapco 1 October 26, 2004 09:47
Short Course: Computational Thermal Analysis Dean S. Schrage Main CFD Forum 11 September 27, 2000 17:46


All times are GMT -4. The time now is 09:47.