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

Discrete Adjoint giving garbage values

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   March 3, 2018, 08:25
Default Discrete Adjoint giving garbage values
  #1
New Member
 
Manish Kumar Mishra
Join Date: May 2015
Posts: 1
Rep Power: 0
Manish Kumar Mishra is on a distinguished road
I was previously using continuous adjoint solver for gradient computation. I decided to try Discrete Adjoint once but I am facing a problem here.

My direct simulation works, so I have a flow solution for the adjoint solver to use. I am also able to use the Continuous Adjoint solver to compute the gradient but when I tried running the Discrete Adjoint solver, it runs and residual values drop by 10 orders but the solution is way far off and when I check the adjoint variable contour, it seems terrible. With discrete Adj solver, the solution blows up!

I thought the problem was with my problem but I am facing the same problem with the config file and grid in QuickStart tutorial airfoil problem. Continuous adj works but not discrete adj.

I tried changing a few setting but I think those shouldn't make any difference. Has anyone faced this problem? Or if you can guess it and suggest a few things to try, I will be glad.

Thank you
Manish Kumar Mishra is offline   Reply With Quote

Old   March 7, 2018, 16:35
Default
  #2
Member
 
Ole Burghardt
Join Date: Mar 2016
Location: Kiel, Germany
Posts: 60
Rep Power: 10
Sprotte is on a distinguished road
Assuming that your SU2_CFD_AD is fine and that you are reading in the solution file correctly - does changing the objective function change the behaviour?

Sounds a bit like a problem in that direction...
Sprotte is offline   Reply With Quote

Reply

Tags
discrete adjoint, quickstart, tutorial

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
Shape optimization doesn't converge - Adjoint log file JPBLourenco SU2 Shape Design 0 December 11, 2017 09:41
Discrete Values for Mesh Motion UnderwaterAlex CFX 2 February 21, 2008 19:21
Minimization discrete values. nico Main CFD Forum 0 December 14, 2006 12:03
Discrete Boundary Values Rhydar CFX 0 July 13, 2002 09:20
IPALL giving NULL values cfd guy CFX 0 November 29, 2001 11:51


All times are GMT -4. The time now is 01:07.