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

SU2_DOT blow-up during Shape Design

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

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   November 28, 2018, 14:00
Default SU2_DOT blow-up during Shape Design
  #1
New Member
 
Join Date: Mar 2011
Posts: 2
Rep Power: 0
Oliver is on a distinguished road
Dear all,


I've ran into some problems while running an optimization process for an airfoil. More specifically, the SU2_DOT component blows-up upon first starting. The error is "Initial Mesh Sensitivity Residual= NaN".



I'm attaching the configuration file used for the procedure. The discrete adjoint solver has no issues with this configuration and the mesh, successfully converging to a stable value for the geometry sensitivity, and roughly 8 orders of magnitude drop in the adjoint variables. Similarly, the flow solver converges using a Cauchy condition on the drag (up to 1e-7), and 7-8 orders of magnitude drop for pressure and turbulence residuals.


The grid I used has only QUAD cells, and is relatively well refined, with Y+ < 1, a 1.15 growth ratio for the estimated BL region and around 300 grid points around the wall. I've also tried to maintain high grid quality throughout, so I don't believe this is the source of problems (and the good converge of SU2_CFD confirms).



So far, the changes I've attempted in the grid deformation procedure have been unsuccessful, but they have been rather trial and error, not having much knowledge related to grid deformation algorithms.



Does anybody now a more robust setup so as to avoid blow-up? Any help in this direction would be much appreciated.


Cheers,
Oliviu
Attached Files
File Type: zip SetupIncHHOptiFoil.zip (7.3 KB, 6 views)
Oliver is offline   Reply With Quote

Old   April 26, 2019, 09:26
Default
  #2
Member
 
tom pratt
Join Date: Jan 2016
Posts: 55
Rep Power: 7
tomp1993 is on a distinguished road
Hi
Try:
listing all of your DV's in DV_KIND (separated by commas and spaces) and DV_PARAM (separate each set of brackets with semicolons and spaces).
using KIND_ADAPT=NONE and ADAPT_BOUNDARY=YES (this might do nothing but i use it and it doesn't hurt)
also just be aware that some of your surface marker names in DEFINITION_DV are 'AIRFOIL' whilst others are 'airfoil'. SU2 is case-sensitive.
i tthink i may have started a thread on the same issue as this previously so have a scroll through the forum and that might be more helpful than what i'm suggesting now.
best wishes
Tom
tomp1993 is offline   Reply With Quote

Old   April 26, 2019, 09:27
Default
  #3
Member
 
tom pratt
Join Date: Jan 2016
Posts: 55
Rep Power: 7
tomp1993 is on a distinguished road
P.S. it might help if you post the output of SU2_DOT as it may give some insight.
tomp1993 is offline   Reply With Quote

Old   July 27, 2019, 02:24
Default Sensitivity analysis failure
  #4
New Member
 
Angu Praveen
Join Date: May 2019
Posts: 13
Rep Power: 3
angupraveen is on a distinguished road
Dear all,

I'm trying to do a 3D SE2A Aircraft wing optimization using SU2. Unfortunately, I am unable to get the following things working.

1. The solution doesn't converge even after 5000 iterations both in ADJOINT and DIRECT solvers. I mean it keeps computing until the max iter value.

2. After the iterations are done, I tried to compute the sensitivity using SU2_DOT_AD and it gives of_grad.dat file with '0' as the value with the following message before

"Design variable (FFD_SETTING) number 0."

Any help would be highly appreciated

Thanks in advance

Angu
angupraveen is offline   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
Problem with the example "Constrained shape design of a transonic turbulent airfoil" geyan SU2 1 November 28, 2018 05:17
Error while running "Constrained Optimal Shape Design of a Fixed Wing" tutorial balav94 SU2 1 September 29, 2018 12:52
Problem with Tutorial "Constrained Optimal Shape Design of a Fixed Wing"" MarcF SU2 Shape Design 3 December 9, 2016 04:30
Diverging Tutorial: "Optimal Shape Design of a Rotating Airfoil" Clancy SU2 2 April 24, 2015 13:18
Info: Short Course On Thermal Design of Electronic Equipment Arnold Free Main CFD Forum 0 August 10, 1999 10:18


All times are GMT -4. The time now is 05:06.