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beschadigunc June 1, 2022 09:21

Supersonic Convergence
 
Hi guys im pretty new here and also relatively new into CFD ,

I have been having some question marks regarding my convergence .

So the current sim that im running at the cluster has 97 Millon cells and I believe a pretty good mesh the wally values are between 0.5 and 3.8 also has grid sequencing initialization.

it is a rocket running at mach 1.2 and I used 25/mach for CFL number. It is running in freestream which has enough gap to propagate the pressure.

But with all these I get this kind of residuals even though the values converge to something Im not sure if the results are reliable or not nor was I able to find some reference wind tunnel paper so that I can check my physics .

image :

https://ibb.co/BN8WV1Z

Should I post it somewhere else ?

aerosayan June 1, 2022 14:08

Your image link is not working. Had to guess the real URL. This one works : https://imgbb.com/BN8WV1Z


Experts can see the image and help you now.

beschadigunc June 1, 2022 18:01

Quote:

Originally Posted by aerosayan (Post 829093)
Your image link is not working. Had to guess the real URL. This one works : https://imgbb.com/BN8WV1Z


Experts can see the image and help you now.


Thanks mate

JBeilke June 2, 2022 07:36

  1. Residuals don't tell you, if a simulations gives correct results.
  2. Your residuals look not bad. Probably you just need some more iterations (maybe 2000)
  3. CCM+ usually gives you normalised residuals. So you only see, that they go down (or do something esle). Go to "Monitors ..." and switch off the normalisation to get the absolute values.


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