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Convergence in a supersonic intake

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Old   November 14, 2023, 01:50
Post Convergence in a supersonic intake
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Adithya Ajay
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Hello there,
Hope all are doing well, I will directly jump in to the problem

My simulation of supersonic intake is not converging after a certain limit. Instead its oscillating. I know shock wave boundary layer interactiuons has inherent unsteadiness associated with it , so the residulas may oscillate while doing steady state analysis. But is there any way to reduce the residuals bit more?

In some cases, after oscillating for long iterations, temparature is getting limited by fluent. I made temparature contour and found that I am having extremely high tempearture outside my intake ( on the tip of external domain). Why this happens?

Images are attached here

1. Residual values after detecting divergence due to excessive temperature change.
274K Residuals (Divergence detected).png

2. Temperature contour after divergence detected
Excessive temperature change 2.png

My mesh is very fine inside the intake !!
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Old   November 14, 2023, 18:23
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Alexander
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AlexanderZ will become famous soon enoughAlexanderZ will become famous soon enough
that's because of mesh
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Old   November 15, 2023, 08:13
Default Please elaborate
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Adithya Ajay
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Is it because of mesh inside my intake or outside ( external domain). Min orthogonal quality is 0.9 , Max skewness is very less , but Max aspect ration is in the range of 100. Another thing I noticed on the mesh is : since I used stretching in Y direction to have Y+ 1, on the top side of the external domain cells are stretched perpendicular to flow direction.
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convergence check, supersonic internal flows, temperature limited

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