Manored, on 27 March 2018 - 06:34 PM, said:
Comparing humans in water to mechs in water is silly, mechs are much stronger, much denser, and have a much larger mass in relation to their surface area. I personally have no idea if such beasts would be slowed down in water at all. In fact, is the main limiter of their speed even air resistance? To me it looks like the main limiters for mech speed would be how quickly they can move their legs and how much mechanical stress they can take, not air resistance.
Water is 784 times more dense than air. There are 2 main types of aerodynamic/hydrodynamic drag: 1) skin friction drag, and 2) pressure drag (a third one related to pressure drag on a wing/foil is called induced drag).
On a large round/cylindrical body (like a leg cross section) pressure drag will dominate. Pressure drag is a function of density and skin friction drag a function of viscosity and density.
Fun experiment if you have a pool and old bowling balls: drop a smooth one and then one that is roughened up surface. Rough bowling ball will fall faster due to boundary layer flow staying attached longer to the back of the bowling ball, which in turn lowers pressure drag -- even though skin friction drag will be higher.
Bottom line, if the Mech cannot clear its feet from the water its going to be slowed down by water, its just physics. The stress on the structure would probably be enough to damage it if was moving full speed THROUGH water. Its not just the density, but the fact that as acceleration increases the drag forces increase by the square. Thats why we cannot move our arm through water as fast as in air. Sure a mech is more powerful but it would have to also be able to handle the massive increases in stress...
Anyway enough armchair physics for today. I say let water effect movement - wouldn't that be a cool way to mitigate faster mechs in places like the swamp etc... force them to follow you into the water. It would liven up game play in my opinion.