I have a question on methodology for the airfoil guys here.
I'm running the candidate airfoils for my motorglider through XFoil, compiling a table of numbers from which I hope to select a final airfoil for the design. One of the cases I want to run is to select some mid-range lift coefficient and then get comparative numbers for each airfoil, both "clean" and "dirty". Don't much care what the absolute numbers are; I'm just looking to see how the airfoil performance changes when it accumulates bugs or dirt in the real world.
In a wind-tunnel, NACA/NASA wraps the leading edge back to about 0.08 chord in rough-grit sandpaper. Is there a standard methodology to simulate this in XFoil? My own guess is just to set trips for the laminar-turbulent transition at the leading edge on both the upper and lower surfaces, and leave it at that. Is this method likely to produce realistic results, or is there something more sophisticated I should be doing? I don't see any guidance in the XFoil manual, nor in any of my other references.
Thanks in advance for any advice you can provide.
I'm running the candidate airfoils for my motorglider through XFoil, compiling a table of numbers from which I hope to select a final airfoil for the design. One of the cases I want to run is to select some mid-range lift coefficient and then get comparative numbers for each airfoil, both "clean" and "dirty". Don't much care what the absolute numbers are; I'm just looking to see how the airfoil performance changes when it accumulates bugs or dirt in the real world.
In a wind-tunnel, NACA/NASA wraps the leading edge back to about 0.08 chord in rough-grit sandpaper. Is there a standard methodology to simulate this in XFoil? My own guess is just to set trips for the laminar-turbulent transition at the leading edge on both the upper and lower surfaces, and leave it at that. Is this method likely to produce realistic results, or is there something more sophisticated I should be doing? I don't see any guidance in the XFoil manual, nor in any of my other references.
Thanks in advance for any advice you can provide.
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