[ufocfd]

I have recently been running rhoSimpleFoam at Mach 2.0 freestream condition using a spaceship geometry. I have been wrestling with it for a couple of days trying to get the convergence better, but still having problems. I have run rhoSimpleFoam many times in the past, and thought I had good (reliable) fvSolution and fvSchemes files, which normally work for Mach 2.0 conditions but this time there was more difficulty. Also when going from OF10 to OF11, I noticed a couple of error messages:

https://drive.google.com/file/d/18GO...wWH3xs5LO/view (image1)

https://drive.google.com/file/d/1aDC...tvCczyk6n/view (image2)

I fixed the 1st issue by adding this line to the fvSchemes file:

div(phi,(p|rho)) Gauss upwind;

(I don't know if this is correct, maybe someone can advise???)

I fixed the 2nd issue by adding/changing the controlDict file:

select all;

My fvSolver:

https://drive.google.com/file/d/1WV0...eGkNUm02f/view (image3)

My fvSchemes:

https://drive.google.com/file/d/1eOW...t6HrnuJoG/view (image4)

My fvConstraints:

https://drive.google.com/file/d/1llE...wBCDAqNwI/view (image5)

The sort of convergence I was getting was like this:

https://drive.google.com/file/d/1t7v...sdzxJrPBO/view (image6)

I tried many different things but the best one seemed to be reducing the relaxation parameter on "e" from 0.2 to 0.02, which had the following effect on convergence:

https://drive.google.com/file/d/1eeY...MArj2BJls/view (image7)

So - this may help other users struggling with rhoSimpleFoam, or maybe someone has some advice on how to improve the solver setting and convergence further?

The final result looks like this after 2000 iterations (surface density contours):

https://drive.google.com/file/d/1D8h...f3rI8oLEu/view (image8)

The final convergence was like this:

https://drive.google.com/file/d/1AoO...fdEK17JvT/view (image9)

Giles.

[arjun]

Why don't you use SIMPLE consistent as yes.