Fluctuation in Pressure distribution over the airfoil

asinghk · July 25, 2023, 13:04

Hi,

I am trying to simulate incompressible flow over NACA 2412. At the frond leading and trailing edge, I am getting fluctuation in pressure. I am new to this and could not figure out the reason whether it is mesh of numerical scheme?

bigfootedrockmidget · July 26, 2023, 04:27

Do the residuals converge to machine precision? That's the first thing to check. If they get stuck at a high residual, then you first have to make it converge.
Is it convergence?
-> Lower CFL, improve mesh, switch to different numerical scheme

Is it the mesh?
-> Refine the mesh, reduce y+, increase nr. of cells overall, increase mesh quality and you will know the impact of mesh refinement and quality improvement

Is it the numerical scheme?
-> Switch to a different numerical scheme: MUSCL on/off, green-gauss or Weighted LEst Squares and you will know the impact of the numerical scheme

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July 26, 2023, 04:27		#2
bigfootedrockmidget Senior Member bigfoot Join Date: Dec 2011 Location: Netherlands Posts: 679 Rep Power: 21	Do the residuals converge to machine precision? That's the first thing to check. If they get stuck at a high residual, then you first have to make it converge. Is it convergence? -> Lower CFL, improve mesh, switch to different numerical scheme Is it the mesh? -> Refine the mesh, reduce y+, increase nr. of cells overall, increase mesh quality and you will know the impact of mesh refinement and quality improvement Is it the numerical scheme? -> Switch to a different numerical scheme: MUSCL on/off, green-gauss or Weighted LEst Squares and you will know the impact of the numerical scheme