3 ms·
This is cool and everything but it distracts from the fact the water drag is 2 (maybe 3?) of orders of magnitude larger than air drag. It might have been a bet
by zackmorris 10y ago
This is cool and everything but it distracts from the fact the water drag is 2 (maybe 3?) of orders of magnitude larger than air drag. It might have been a better investment to install vortex generators on the hull (these work like the dimples in golfballs to reduce the vacuum formed behind the moving body). I may be wrong about this, for example if laminar flow is better in an incompressible fluid.
https://en.wikipedia.org/wiki/Vortex_generator https://en.wikipedia.org/wiki/Vortex_generator
- semi-extrinsic 10y agoAt speeds well below 10% of soundspeed, as for a ship superstructure or for most cars, air is by a very good approximation incompressible.
- zazen 10y agoI find this comment very puzzling. A team of experts spent months or years designing and building a ship. Are you really suggesting they just forgot about the hydrodynamic drag? If the first thing that pops into your head was actually a "better investment", don't you think they might have managed to think of it too?
- zackmorris 10y agoI'm sure they optimized hydrodynamic drag too. My point was that aerodynamic drag is so much lower that the bow of the ship could have been shaped like a pokemon and it would have made almost no difference on overall efficiency. An analogy would be putting a nose cone on a train. It looks cool and everything but the train is still going to lose half its thermodynamic efficiency (or more) just burning oil. Whereas jumping to electric reclaims all that, and I was trying to make a similar point that higher gains might be found elsewhere for shipping.