300knt torpedo

[Guillermo]

But the US of A seems to be researching the thing...
http://www.onr.navy.mil/sci_tech/eng..._highspeed.asp

[yipster]

wham, late last night i see that thing flying over the screen again on discovery.
in the same marine machines doc i saw bofors bearcam driven torpedo i cant find much info on.
many other expensive intelligent attack and counter measures later i fell in sleep

[zerogara]

beercan torpedo flying over the screen......

Say that again!

[safewalrus]

yeah escaped from a different thread!

[Wellydeckhand]

We invented flying chopstick looooong time ago........

[yipster]

bearcam frends, not beercan
than again is that the good name for an engine like a colt, having the cilinders around pumping like bullits driving the centerline axle with circular wobbeling cam and/or crank. if not clear i show a scetch but rather find some tech papers on such ( "normal" topredo ) engines.

Now whats happened?

Cheers!

[Wellydeckhand]

Touchy arent we about bearcam........ sorry wrong prescription..... gettin old

[FranklinRatliff]

http://www.ctechdefense.com/speed.html

2509 West 19th Street, Port Angeles, WA 98363
PHONE (360) 452-2275 * FAX (360) 452-2297 * info@ctech.esdcorp.com

Underwater Speed Limits
(Following is the full text submitted to Scientific American. The published version was shortened for editorial reasons.)

"There appear to be two conceptual ways of approaching supercavitation. The generally accepted one derives from propeller cavitation theory and holds that the water is essentially boiled by dropping its pressure via abrupt acceleration. This creates a source of gaseous water vapor which creates the cavitation bubble. It is generally assumed that the cavitation bubble is filled with this water vapor. Indeed, in low speed (say torpedoes) supercavitation applications the cavity size is usually enhanced with ventilation gases. This fits well with the understanding that gas creates the bubble in the first place and appears to work well within that context. It also fits comfortably in the general framework of marine engineering.

Last September, at an ONR sponsored Supercavitation Conference, Dr. Kirschner (of Anteon Corporation) and I were discussing the idea of a theoretical speed limit for supercavitating objects, assuming material strength issues could be overcome. As previously mentioned, conventional wisdom holds that the cavity is created by the water vapor and therefore, at some speed, the volumetric rate at which vapor can be generated will become insufficient to support the formation of a cavitation bubble which will clear the body. In other words, at some velocity the rate at which the water boils will become insufficient to fill the volume of the "hole" in the water created by the passage of the projectile and the cavity will collapse.

For whatever reason, I have a different mental picture of how the bubble is created, perhaps due to my background in hypersonics in graduate school. In that field discontinuities and rarified flows are encountered in the course of normal business. I do not know if anyone else shares this view but Dr. Kirschner and I have discussed it at some length. In any case, I believe the process is fundamentally one of momentum transfer. The cavitator, be it a disk or cone or whatever, imparts a significant radial velocity (relative to the axis of flight) to the water it comes in contact with. In effect the water is thrown violently to the side. It therefore has a high radial momentum that is resisted by the pressure of the water around it. This pressure serves to slow its radial velocity and will bring it to a stop over a finite time. The accepted definition of cavitation number is compatible with this idea. In the meantime, assuming a circularly symmetric cavitator, a round "hole" has been created in the water. What is in this hole, other than the projectile? I believe it is a vacuum, at least initially. Of course the water on the interior face of the bubble begins to boil, but it can only boil so fast, even in a hard vacuum. At slow velocities the rate of boiling can create a fairly decent partial pressure of water vapor in the cavity. In the limit case, as velocity increases, the pressure inside the cavity in the vicinity of the projectile will go to zero. Eventually the pressure acting on the water will reverse its radial velocity and cause the cavity to close. However, the projectile will be long gone by that point. If this approach is correct then, except for finding a material to withstand the steady state stagnation pressure, there may be no hydrodynamic upper limit to the velocity of a supercavitating body.

In any case, perhaps there is room for both viewpoints. In fact, they may very well be opposite sides of the same theoretical coin. I would certainly be interested to know what other people in the field thought of this approach. Perhaps it would provide an interesting topic of discussion within the article?"

[yipster]

thats food for thought ...
i was wondering along why super boiling could occur in seawater

[safewalrus]

few beercans you wn't give a damn and put his back where it belongs!

[Wellydeckhand]

Mmmmm...... Cheer....... glup.... glup...... HIC****

Not deleted at all! Just getting old and phorgetphull, & can't remember where I left anything! (Meaning I posted this someplace else!...but now will post it here for posteritys sake!

For example..

Consider this..

I saw the thread hereabouts - regarding a 200/300mph rocket propelled torpedo???.

Now imagine for just ONE second...how fast would a Nuclear powered torpedo travel if the nuclear energy were converting the water to steam and generating the air / oxygen for the bubble to encase it????

Would it go faster than the Russian one?

I'm thinking it might..

BUT - taking what I suspect to be true about TIME having an equal amount of potential energy, to Mass (ergo aforelentioned Nuclear propulsion) If such a weapon were propelled by Time energy (and we know as we approach lightspeed (infinity)Length decreases Mass increases & Time shortens etc etc...)

Well if it's near lightspeed (infinity) and time is shortening - this torpedo could actually GET there BEFORE it left the submarine! (Ta daaah - drum roll!)

Thats right - send a torpedo BACKWARDS in time....

So consider this..

A ship detects a 300mph torpedo approaching from 50 Nm away, or 10 mins to impact...what to do?

Easey, send a torpedo back in time to 5 mins BEFORE the 300 MPH one was launched and two things happen..

1. the sub that sends the 300mph torpedo gets destroyed

2. The midwater torpedo it launched ceases to exist!

Problem solvered!

Just call me First mate gunner "time lord"!

Sooo, time for more pills eh?

Cheers!

[Guillermo]

Originally Posted by FranklinRatliff

....In any case, perhaps there is room for both viewpoints....

There is even room for new computer games...!
http://www.deepangel.com/

Two interesting (and more serious) articles:
http://www.supercavitation.com/Super...evelopment.pdf
http://www.supercavitation.com/SUPER..._Savchenko.pdf

[Guillermo]

It seems Iran has tested supercavitating torpedoes also.
Here the news (In spanish): http://www.elmundo.es/elmundo/2006/0...144050685.html