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> This oval (called a separatrix) has the special property that no wind flows through it at all. It acts just like a solid surface. We have already assembled a reasonably accurate simulation of how air flows around an ellipse in some confined space like a wind tunnel!

My understanding of airflow simulation (undergrad-level at best) is that the correct boundary condition is almost without exception the no-slip one: air should be stationary at the surface of each object, not just have zero flow across it.

Am I correct that the calculation mentioned above really only applies to the "dry liquid" scenario where there is no drag and zero viscosity?




You are correct! The simulation as written does not handle the no slip condition. The simulated "air" is inviscid and irrotational. You would need to tackle a few more things in order to have a really accurate simulation.


Thanks for the awesome write-up.writer's note. The first paragraph of your conclusion would have served better as your introductory paragraph.




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