SimScale CAE Forum

Problem simulating high airspeed over airfoil

I am trying to get a compressible wind tunnel test of a wing. The wing is at an altitude of 43000 ft and a airspeed of 250 m/s (mach 0.85). I want to see if the wing is viable at this speed, and eventually compare three different wing planforms to see which is best.

I filled in all values correctly, I think. I changed pressure and viscosity, k and omega I kept the standard value. But every time i try to simulate it it says “The maximum number of iterations exceeded” Is it possible to simulate such a high airspeed? could the low quality mesh operation has something to doe with it?

my project

Hi @timovM,

The first thing I see here is the mesh:

The bounding box needs to be much bigger in all dimensions, also you should inflate the boundary layer. This is just good practice advice and might not be your issue.

I find when performing simulations at high velocities stability issues occur, this can be reduced by ramping the velocity via a CSV upload. Adjusting the gradient of the ramp, and reducing the relaxation factors should start producing stable runs.

Kind regards,

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