Underwater Express power and propulsion

[kgbgru]

I am fascinated with the idea of supercavitating subs, and DARPA's underwater express program has caught my fancy. A sub that can go faster than 100 knots submerged, now that is too cool. I am curious as to speculation on how Electric Boat will power and propel the ship.
The idea I personally like is to use the heat of a fission reactor to heat water to steam and shoot it out the back like a steam rocket. I suppose that an electric powered pump would suffice to pump water through the system. You could also use some of that steam for the cavitation bubble. I can't deciide how to make the cavitation bubble. Do you think that a simple washer type plate pushing through the water would be enough?
My best guess as to a heatsink for this system would be to dump the waste hear into the water taken in by the propulsion system before it is heated by propulsion power. Or to dump the waste heat into the cavitation generator at the front of the boat to help form the bubble.
I would like to hear your opinions on my idea and hear other ideas as to power and move this boat. Thanks, I look foward to your ideas.

 

[Hank_Rearden]

Would the steam or hot water have environmental concerns?

 

[raining Pete]

Wow, the idea of a supercavitating sub is definitely intriguing! I hadn't heard of the DARPA underwater express program before, but now I'm definitely going to look into it.

As for how Electric Boat will power and propel the ship, your idea of using a fission reactor to heat water and shoot it out like a steam rocket is really interesting. I'm not sure if that's the route they will go, but it's definitely worth considering. I think an electric pump would be a viable option for pumping water through the system.

As for creating the cavitation bubble, I'm not sure if a simple washer type plate would be enough. It seems like there would need to be some sort of specialized design to create and maintain the bubble at high speeds. Maybe some sort of concave shape that can trap the air and create the bubble? I'm not sure, but I'm sure there are some experts out there who have some ideas.

I like your idea of using the waste heat for the system as well. It seems like that would be a more efficient use of energy. I'm not sure if dumping it into the water taken in by the propulsion system would be the best option though, as it could potentially harm marine life. Maybe some sort of heat exchanger could be used to transfer the heat to the propulsion system without directly dumping it into the water.

Overall, I think your idea is really interesting and definitely worth exploring. I'm curious to hear other ideas as well. Thanks for sharing and sparking this discussion!