[Physics] What would be an appropiate shape for a parachute

aerodynamicsdragfluid dynamics

I'm trying to design a parachute that minimizes the descent velocity, but I'm not sure what shape I should use.

From what I've read, ellipse-shaped parachutes are too aerodynamic and minimize drag, while squares are good enough to maximize drag, but I've read this from very unreliable sources and unfortunately I've never taken a fluid dynamics course so I'm not sure if those answers are right.

Best Answer

You want your parachute not to be a parachute, but a wing. The difference is that it has horizontal velocity, and the air flows smoothly over the top and bottom surfaces.

In addition, you want to minimize drag, because sink rate is proportional to drag. The main way to minimize drag is to minimize speed. So it needs forward speed, but no more than necessary.

Check out paragliders, because that's what they do. I've seen these things in action. They stay up a long time.