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

SU2 RANS Performance

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

Like Tree1Likes
  • 1 Post By fpalacios

Reply
 
LinkBack Thread Tools Display Modes
Old   August 16, 2013, 18:06
Default SU2 RANS Performance
  #1
New Member
 
Gaetan Kenway
Join Date: Aug 2013
Posts: 2
Rep Power: 0
gkenway is on a distinguished road
Hi guys

I have recently been playing around with SU2 and have a couple of questions about the RANS cases.

First of all, how long does the turbulent oneram6 case supposed to take using the turb_ONERAM6.cfg file? For me it took about 13,000 iterations to drop the residual down to 1e-6, or about 3.75 hours of wall time on a single processor. It looks like there was no multigrid used however. Does the multigrid help much in this case? Are they any other options that would significantly speed up with calculation or is this performance typical?

For comparison, I ran a 128,000 cell M6 grid though SUmb (JST scalar, SA, using 3w MG without MG startup), on a single processor down to 1e-6 and that took about 35 minutes on a single processor.

Considering that SU2 grid has about 40,000 cells, that would make SUmb, over an order of magnitude faster. Is this sort of performance differential expected?

Thanks and keep up the great work!

Gaetan
gkenway is offline   Reply With Quote

Old   August 18, 2013, 00:26
Default
  #2
Super Moderator
 
Francisco Palacios
Join Date: Jan 2013
Location: Stanford, CA
Posts: 301
Rep Power: 5
fpalacios is on a distinguished road
Hi Gaetan,

Thanks a lot your your kind email. As you know, to find the right parameters in a CFD solver is an Art. For this particular problem, please find attached my convergence and the config file that I'm using. On a single processor, it took me 642 iterations and 11.6 min of wall time to drop the residual to 1e-6 using the current developers version of SU2 (https://github.com/su2code).

An apples to apples comparison with other solvers is very important for us, and we will participate in a special session during the next SciTech in which SU2 will be compared with the most important solvers in US.

Anyway, shape design, it multidisciplinarity capability, and flexibility are the most important characteristics of SU2. Its object oriented structure is very useful despite the performance could be inferior to a pure C code. For that reason we have a collaboration with Intel to improve the code vectorization and exploit all the capabilities of an Intel Xeon Phi platform (http://www.intel.com/content/www/us/...hi-detail.html).

In short, as far I know, the algorithmic implemented in SU2 is as good (or better) than the one implemented in SUMB. As you know SUMB uses pure C and a structured data storage (that is a plus in performance). However, as you know, when you are interested in complex geometries a structured grid could be orders of magnitude bigger than an unstructured one (assuming that it is possible to generate the multiblock structure grid without overset).

Thanks a lot for using our code and your encouraging words,

Best,
Francisco



Quote:
Originally Posted by gkenway View Post
Hi guys

I have recently been playing around with SU2 and have a couple of questions about the RANS cases.

First of all, how long does the turbulent oneram6 case supposed to take using the turb_ONERAM6.cfg file? For me it took about 13,000 iterations to drop the residual down to 1e-6, or about 3.75 hours of wall time on a single processor. It looks like there was no multigrid used however. Does the multigrid help much in this case? Are they any other options that would significantly speed up with calculation or is this performance typical?

For comparison, I ran a 128,000 cell M6 grid though SUmb (JST scalar, SA, using 3w MG without MG startup), on a single processor down to 1e-6 and that took about 35 minutes on a single processor.

Considering that SU2 grid has about 40,000 cells, that would make SUmb, over an order of magnitude faster. Is this sort of performance differential expected?

Thanks and keep up the great work!

Gaetan
Attached Images
File Type: jpg history.jpg (71.3 KB, 42 views)
Attached Files
File Type: zip turb_ONERAM6.cfg.zip (4.0 KB, 27 views)
aero_amit likes this.
fpalacios 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
Incorrect calculation of forces/moments coefficients with older versions of SU2 diwakaranant SU2 2 August 16, 2013 04:17
SU2 suite has moved to GitHub! fpalacios SU2 News & Announcements 0 August 12, 2013 02:07
Welcome to the Stanford University Unstructured (SU2) forum! economon SU2 0 January 7, 2013 03:48
New SU2 Forum Opened at CFD Online pete Site News & Announcements 0 January 5, 2013 18:59
Performance of RANS for incompressible jet Fab Main CFD Forum 4 October 10, 2007 13:37


All times are GMT -4. The time now is 00:29.