3 ms·
- Most of the popular explanations are misleading, the others are incomplete. - The real answer is so hard to compute that there is a million dollar prize atta
by GuB-42 5y ago
- Most of the popular explanations are misleading, the others are incomplete.
- The real answer is so hard to compute that there is a million dollar prize attached to it.
- Today, we design planes using approximations and trial-and-error. It works well because we are very experienced in designing planes, sometimes at the cost of many lives, but it is not exactly a "first principles" approach.
- scarier 5y agoI mean, you can get deep into epistemology and argue that it's impossible for anyone to truly know anything, and tautologically all of engineering requires approximation in some way, but our modern understanding of aerodynamics is absolutely a "first principles" approach (the principles being conservation of mass and momentum in a viscous fluid), even if there are still some aspects of trial-and-error on the aircraft hardware level. Despite the open mathematical problem of the existence and smoothness of Navier-Stokes that you mentioned, the equations are a fantastic tool that have enabled us to make startlingly accurate calculations of lift, drag, stability, and performance, despite our inability to do direct numerical simulation at the Kolmogorov scale on usefully-sized things.