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Steam Powered Underwater Jet Engine
Bob Vila's Hammer writes "An Australian engineer, Alan Burns invented a very efficient underwater steam powered jet engine. "Steam that is produced from a petrol or gasoline fueled boiler emerges at high speed from a rearward-facing ring-shaped nozzle into a cone-shaped chamber. Shock waves created as the steam condenses are focused by the chamber to blast water out of the back. Besides powering watercraft pretty efficiently, it can also be used as an extremely robust pump. Pretty Cool."
I remember reading in a super-cavtation article about underwater engines like that - basically "underwater jet-engines" - I mean, of course it's not quite true, it operates on different principles, but the functionality is pretty similar.
;-)
btw, super cavtation is where you make the nose of your _insert_vessel_here_ blunt but it goes so fast that the vapor pressure drops until the vessel (usually a torpedo / bullet / whatever) would be in an airbubble (technically steam bubble! - though there are dissolved air that boils into the bubble too) that it creates itself (and maintains) and hence has no liquid drag for the rest of the vessel (as in, besides the blunt nose).
The engine I read about was actually reacting seawater directly with aluminum shavings and expelling hot steam (or something like that). I am pretty sure there were something else but I can't remember what it was (I don't think it was iron-rust, though, for all of you thinking of thermite). Anyway - neat stuff; should change underwater combat a whole lot.
should get myself one of those to go war(ship) driving
My life in the land of the rising sun.
why electrolosys of course, just like in all the serious boats out there.
Imagine if the drive which produces steam is not desiel or petrol, but nuclear!
Enough "air" and steam for everybody.
Moreover, imagine if the sub doesn't use neutral bouyancy but flies through the water.
One thought though, if you're doing 90 knots underwater when the sea is full of debris, you might want really good maps and a kick ass gps+VR rig to guide you through the canyons, because I doubt sonar will be able to image for you fast enough.
Which seems a little disappointing. I liked it better thinking of a contraction of "masticate" and "lacerate"
"Even if you are on the right track, you'll get run over if you just sit there" - Will Rogers
I don't know. It depends on how clever we are. The stealth bomber is jet propelled and yet the can hush it by mixing cold air with the hot exhaust and carefully shaping the jet so that you only hear it with sensative microphones when its directly overhead. Or so the govt said in 1991 on the news.
I'll refer to your paragraphed by numbers.
1. The article says it is quiet, but doesn't specify if this is because noise is ultrasonic, or the process is just plan quiet. Regardless a ship doesn't avoid submarines by being quiet. It avoids submarines by using bloody huge active sonar, propulsion noise hardly matters, a ship still makes a lot of noise carving through the water, unlike a sub it is not completely covered in the same medium, but two (air, water).
Also torpedoes do not home on noise (aka passive sonar), they home on returned "pings" from active sonar, who cares if they know where the torp is, if they have no hope of out running it.
The article doesn't speculate that this will necessarily make ships faster. It will certainly mean less drydock mantainence, and better reliability from the drive.
2. Until they develop completely unjammable communication links between machine and pilot, with zero possibility of being hijacked by the enemy, there will always be a need for manned aircraft.
Even if we get sentient un-manned aircraft, would you trust it carrying a bomb? Would you want to take responsibility when it decides to bomb a school?
3. On the contrary I think many of them would love to do something to stop their men from being killed, so long as they don't lose control of air defence. eg: SAM sites were proposed to be run by the army, so the airforce fought tooth and nail when it was suggested that interceptors, etc were unnecessary.
"zero possibility of being hijacked by the enemy". THAT possibility already exists. Its quite simple. You have say 2 flash memory cards (or other solid storage device where the contents are sealed), stored in a sealed metal housing with a circuit board and a small controller. A tiny wire antennae feeds atmospheric radio noise...essentially a completely random source...to the chip. It fills the 2 cards up with this string of numbers. When it comes time to deploy the aircraft, one card is plugged into the remote console, one card into the aircraft. COMPLETELY impossible to hack, as all communications would be encryted using this one time pad. No, not even quantum computers can break this kind of code.
As for jamming : a high frequency beam is directed from an antennae dish on the plane to a satellite. As long as the satellite is intact, and knows approximately where the aircraft is it can effectively ignore all other sources of EMF. There is absolutely no way to jam this kind of link(short of detonating nukes in the atmosphere, or as of yet nonexistant conventional emp weapons.). Physical destruction of the satellite is a possibility...a very powerful missile or laser on the ground could do it. Still, a more sophisticated system would use other remote aircraft circling in the sky as communications relays, again not jammable. And anyways, if the comunications are jammed of course it won't fire any weapons, instead going to some preprogrammed contingency (perhaps circle or fly low to the ground til it needs to return to base?)
As for sentient unmanned aircraft...well, at that point I think I'd be more worried about losing control of the world entirely rather than a few random bombings. Once sentient computers are possible it is pretty reasonable to assume humanity's trek is effectively over. (whether or not humans go on living, they won't be relevant)
From the article: "We know the answer," says Mike Todman, the company's chief technical officer, [..] But he says it will not be revealed until patents are granted.
Now, this is the sort of thing for which patents were made. I can respect these guys for wanting to patent their engine - it's innovative, non-obvious (well, to me anyway..) and they appear to have put a lot of work into it.
One of these patents is worth a thousand "Amazon / 1-click", "SBC / Web Frames" or "British Telecom / Hyperlinks" patents, yes?
I was thinking more of the possibility for torpedo engines - if it's small, cheap, powerful, and fast (and sufficiently fuel-efficient, which the article didn't mention was good or bad about this) it may be more effective for making anti-ship weapons than faster ships.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
... fuel, efficiency, fragility. Consider this:
... as in the Navy's big ships. And how does the efficiency of transferring steam's energy into liquid motion compare to that of a propellor?; and
1) Maintenacnce of Boiler - boilers are not trivial creatures. They run hot and need regular maintenance. And I want to see the boiler that runs on _salt_ water and doesn't have a _big_ maintenance budget (look up salt water evaporators);
2) Efficiency - boilers aren't great at converting the heat energy to steam unless they get quite fancy
3) No moving parts - is a red herring. The question is how fragile are your parts? Little holes get clogged up pretty quickly, not necessarily when running, but when the thing is stopped. And cardboard doesn't compare to what is really out there. What happens when a piece of plywood jams into the throat of the nozzle and blocks, or just restricts, water flow?
It's a neat idea but I think it's a solution looking for a problem.
"Consensus" in science is _always_ a political construct.