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NACA0012 - High Resolution - No convergence

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Old   March 25, 2011, 07:35
Default NACA0012 - High Resolution - No convergence
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Hi,
I can't get my solution to convergence when using the High Resolution solver and medium to fine grids. It only convergences on a very coarse grid. Using the Upwind scheme which lacks accuracy - the solution converges every time !
Mach number is 0.5 and angle of attack 2. With High Resolution I even get negative pressure forces on the wing in x-direction, totally absurd.
What might be the reasons for this behavior and how do I get it to converge ?
Thank you !
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Old   March 25, 2011, 16:39
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Could you try running a high resolution scheme simulation with the results from the upwind scheme to initialise the solution?
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Old   March 25, 2011, 17:09
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I tried that and failed.
However I managed to get it to work, I found out that while increasing the number of grid points in the far field and number of inflation layers I did not increase the number of grid points on my airfoil in the same manner. This resulted in long and very thin inflation layer cells, which seem to cause problems with the High Resolution Solver. So I added more points to my profile, decreased the amount of inflation layers and now everything works very well !
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