CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > Software User Forums > SU2

NASA CRM wing simulation in SU2

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   June 23, 2020, 19:39
Default NASA CRM wing simulation in SU2
  #1
New Member
 
Ranjan
Join Date: Apr 2014
Posts: 24
Rep Power: 8
Ranjan is on a distinguished road
Hello

I am trying to simulate inviscid flow-field around the NASA CRM wing. Even though my dimensions are correct, I get extremely high values for CL and CD ( almost double ) when compared to the design conditions of AOA ~ 2.34 degrees.

I have tried both manual and automatic values for A_ref ( by setting A_ref zero), the manual entry for A_ref being 191.82 m^2.

I have also tried multiple mesh resolutions, varying from 3-9 Million.


Any suggestions ?

Thanks in advance
Attached Files
File Type: txt inv_CRM.txt (7.8 KB, 9 views)
Ranjan is offline   Reply With Quote

Old   June 23, 2020, 21:33
Default
  #2
New Member
 
Join Date: Jul 2019
Posts: 5
Rep Power: 3
hpatel is on a distinguished road
Quote:
Originally Posted by Ranjan View Post
Hello

I am trying to simulate inviscid flow-field around the NASA CRM wing. Even though my dimensions are correct, I get extremely high values for CL and CD ( almost double ) when compared to the design conditions of AOA ~ 2.34 degrees.

I have tried both manual and automatic values for A_ref ( by setting A_ref zero), the manual entry for A_ref being 191.82 m^2.

I have also tried multiple mesh resolutions, varying from 3-9 Million.


Any suggestions ?

Thanks in advance
What is the x-y-z orientation of your mesh? In relation to that, why is the AOA=0 in the config file?
hpatel is offline   Reply With Quote

Old   June 23, 2020, 22:07
Default
  #3
New Member
 
Ranjan
Join Date: Apr 2014
Posts: 24
Rep Power: 8
Ranjan is on a distinguished road
I am not sure what you mean by " why is the AOA in the config file ? "

The flow angle of attack is always defined in the config file. The config file is attached as a .txt file with my post.

Thank you
Ranjan is offline   Reply With Quote

Old   August 24, 2020, 15:13
Default
  #4
New Member
 
Join Date: Jun 2020
Posts: 8
Rep Power: 2
punyaplaban is on a distinguished road
What is the axis of lift in your mesh? Is it z-axis?
punyaplaban is offline   Reply With Quote

Old   September 3, 2020, 14:58
Default Resolved
  #5
New Member
 
Ranjan
Join Date: Apr 2014
Posts: 24
Rep Power: 8
Ranjan is on a distinguished road
I figured out the problem. The axis orientation and the configuration in general were correct. However, Euler flow assumption especially for the CRM wing at design condition leads to spurious ( over-predicted ) aerodynamic characteristics. While one might expect to predict the pressure forces and hence the lift distribution to a reasonable accuracy, the CRM geometry encapsulated viscous effects such as shock-induced boundary layer separation , a phenomenon absent in Euler assumption.

Upon switching to RANS and a computational domain with appropriate near-wall resolution ( yPlus ~ 1 ), the flow characteristics computed were reasonable when compared to other numerical experiments.

Thank you all !
Ranjan is offline   Reply With Quote

Reply

Tags
crm wing, euler, su2

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
SU2 propeller simulation helpmewithcfd SU2 2 October 19, 2020 05:08
Material definition- nasa polymonials oliveira1820 CFX 2 May 22, 2019 08:29
[ICEM] HEX Structured mesh around NASA CMR wing raz ANSYS Meshing & Geometry 1 October 22, 2016 13:21
[DesignModeler] Gap seen in NASA CRM models in designmodeler, not visible on CATIA mayin12 ANSYS Meshing & Geometry 1 June 15, 2016 16:25
Ansys CFX problem: unexpected very high temperatures in premix laminar combustion faizan_habib7 CFX 4 February 1, 2016 17:00


All times are GMT -4. The time now is 05:37.