Magic. Got it.
The pressure drops .7 psi across the wingspan of an Airbus A320 at ~120mph aka take off speed/AoA, the airflow over the wing's low pressure peak is ~400mph.
You want a little secret? If you know the Reynolds number, you can get the same effects in water, air, or honey as long as you have the same Reynolds number. Re# is just the relationship between a fluid's kinetic energy to viscosity. In all fluids, flow goes from laminar to turbulent at ~4,000 Re# it can be higher if carefully controlled, but it's pretty much a constant. This means you can do experiments in water and it will translate well to air as long as the Re# of both experiments is the same.
In practical terms, you can take a full scale model of something and shrink it to a 40% model and have a flow speed 1/10th that of air speed you're studying, and you will have similar results.
Just dropping in to say thank you for the nerd drop. All of that information is really interesting but I have no way to respond to it in a meaningful way. It's kind of like me explaining the finer details of a programming language to an english majour.
If the economics ever allow, I wouldn't mind using modern engineering design tools + modern composites to explore building cars and flying contraptions. I have an idea for a wing like glider that you stand on like a surf board and glide down to the ground. It would need to be made of carbon fiber and have a wing span larger than a snow board but nothing quite as crazy as a glider.
You would basically jump out of a plan with that strapped to your legs and serf out, then ditch it and use your chute for the landing.
Knolwedge like yours would be really useful in building something like that.
This guy tried to build his dream car using just paper and welding: https://www.youtube.com/watch?v=S-IsKm3T2sI
He never finished it. It would have been a lot easier if he designed it first in cad, had moulds built out of the cad and built a composite shell no top of that frame. Mind you, he isn't setup for that.
That's actually pretty cool. I suppose the reason they make gliders the way they do is more for landing than anything. Also it's better to have the low pressure surface free of any obstructions, whereas it's less damaging to lift to have obstructions on the high pressure side, since that side is basically trying to keep air from speeding up. Notice there's not a lot of planes that put big draggy engines over the wings.
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