>>12555574Well, yes, but no. Bernoulli still applies in inviscid incompressible flows (Bernoulli is basically Navier-Stokes with some restrictive conditions applied to it), but it's not enough to describe lift over an airfoil: neither the kite nor the Wright Flyer can be described just by Bernoulli, but Bernoulli still applies to them. To be fair almost all airfoils, to a degree, can be studied within the thin airfoil theory, which basically approximates the airfoil to a line, so in a sense all wings can be considered as thin as a kite's. Still, over an airfoil the air accelerates and slows down, goes faster and slower, and Bernoulli still applies, meaning that there will be lower pressure where the air is fast, and higher pressure where it's slow, but why it's fast where is fast and why it's slow where it's slow is, well, kinda complicated. The point of my previous post is to say that when you consider a wing (or any surface really), for the purpose of calculating lift, i.e. what makes planes fly, in ideal conditions you can ignore the boundary layer and do like the air slipped directly on the surface, where in reality it doesn't because it sticks. It's like: "We want to calculate what makes a plane fly, so for a number of reasons that we know hold true we ignore the boundary layer and the no-slip condition and since the thickness of the boundary layer is like very thin compared to the airfoil of the wing we ignore its thickness too, so we can concentrate on the geometry of the airfoil and all the weird things that it does to the air flowing around it". I'm sorry, I hope it makes sense, I'm rambling, the sleeping pill is starting to kick in. Good night.
