THEORETICAL why don't the NAVY utilize the use of O2 or lighter gasses to achieve MACH SPEEDS with our Subs?

Question

it is currently impossible to achieve manned supersonic or even sub sonic travel under water due to the mass of water right? And the pressures that depth can create,it limits how fast we can go... we could currently go faster with the subs we have by adding horse power.even if we could get enough power into a submersible to go supersonic it would just rip apart like hitting a brick wall. Do any of you think that by basically creating a submersible that looked similar in desighn to an aircraft, with the same wing lift and drag ratios. That by useing air or a lighter element to create and keep a virtual air buble around the ship that it would correct and illiminate the heavy mass problem.Thin making it PROBABLE to achieve MACH + speeds???? INPUT PLEASE thanks

Answer 1

The problem is not the weight of the water, it's the drag of the fluid. Unless you can find some magic way to eliminate the drag in a fluid like water which is so much more than that of a gas, you will be stuck with lower speeds. Even if you had some "magic" bubble around the sub, you would still need to displace the liquid to move the bubble.

Answer 2

Hi,

I don't think it's possible in the way that you describe, the problems being (if I understand your idea):

- Gasses are compressible gas, and water is not, making it difficult to generate a bubble

- Gasses are miscible making them susceptible to dissolution into the water if the pressure were increased (as it would with high speeds behind it)

- Mach speeds in a dense liquid such as water (particularly salt water) would create turbulent fluid flow that could would almost assuredly cause cavitation and loss of control.

- Water has a high surface tension which tends to stick to stuff. it would drag your bubble apart (particularly at high speeds)

- In order to move through the water, a submersed object must displace the same volume of water around (or through) itself to the aft side. At a speed that high, this would be difficult (unless it somehow were piped through the sub which isn't a bad idea).

Hope that helps,
Matt

Answer 3

The question you should be asking is, why would we need a supersonic submarine? The submarine's mission is all about stealth, being as quiet as possible. I don't care what technology you use to reach supersonic speed underwater, it's going to make a hell of a lot of noise, so any potential enemy out there is going to know precisely where it is. Kinda defeats the whole idea of a stealthy submarine.

What would be the purpose of such a sub? If (as I assume) your objective is to reach a target area as fast as possible, there are other platforms (i.e., aircraft) that can do that job better.

Answer 4

The air bubble would still have the same resistance in the water. It has to move the water out of the way, same as the sub would.

You seem to be ignoring the reasons for having subsurface military ships - Stealth. Even a moderately fast sub makes a lot of noise. If you want to go fast, it makes more sense to get into the air. Really fast, then go into space.

Answer 5

Mass isn't the problem, drag is.

But your idea does have merit. The Russians developed a torpedo called Shkval that used this principle. It was rocket propelled and injected gas in front of the torpedo so that it was surrounded by a gas envelope. It travelled very fast, hundreds of miles per hour.

However Mach 1 in water is much faster than it is in the air. The speed of sound in water is 5400 kph (Wikipedia).

Answer 6

there is an major enormous difference between drawing near the speed of Sound and drawing near the speed of light. Getting as a lot as and exceeding Mach a million is a issue in fluid mechanics. An plane purely desires to be shaped impressive and characteristic sufficient engine thrust. that is then conceivable to shuttle by air such that the air receives shoved off to at least one area easily sufficient to allow passage of the plane. Getting as a lot because the speed of light is yet another issue altogether. that is not a count number of studying extra about aerodynamics or engineering an airframe. that is a count number of ways Nature conspires to save the speed of light an similar for all community frames of reference. A effect of that is that, as you attitude the speed of light, it receives more durable to get in route of the speed of light. The closer you get, the a lot less extra % you may pile on. It purely compounds this way continually so it would want to take infinitely lengthy, no count number how helpful your spaceship's engines may be, to get all the way as a lot because the speed of light. It remains for ever and ever out of attain.

Answer 7

No. It's not a feasable idea. You cannot force an air bubble to travel at supersonic speeds under water.

Answer 8

I don't think so, because the water would still need to be moved out of the way wouldn't it? Even if the water didn't touch the skin, wouldn't some force still have to push it aside?