squid like propulsion...???

[yacht picasso]

Good day all....

Does anybody know of any studies, images, or literature that talks about a squid like thruster/propulsion?

Do you know anything about this?
What are your views? (is it feesable)

Thank you

[Guest625101138]

The limiting efficiency is 50%.

It is very effective for escape. There is little energy involved in loading the bladder at rest. So the initial impulse is akin to a rocket and can achieve very high efficiency. I have designed a water rocket driven by compressed air for a movie stunt. It was very effective.

The performance degrades when the water has to be loaded and brought up to speed once the boat is moving. This is the prerequisite to squirt it out of course.

The feature of prop and jet type thrusters is that you do not have to bring the water up to boat speed. It just passes through and the propeller applies momentum to it.

You may think that water entering at the front and being jetted at the back overcomes this but only if it is continuous. As soon as you have a pulsing action that relies on valving at the entry you are bringing most of the water up to boat speed.

I did contemplate a continuous style of thruster based on a bladder. It would work like a peristaltic pump. It would have very high volumetric efficiency. I believe such a system could get efficiencies as high as 70% if well engineered.

Rick W.

[TeddyDiver]

Originally Posted by yacht picasso

Does anybody know of any studies, images, or literature that talks about a squid like thruster/propulsion?

Hunt of the Red October fictional and not so precisely described in the book...

[yacht picasso]

Guys, that is understandable if we are discussing the water burst from cephalopods.... but what about the lateral membranes (on each side of the head) of the squid?

[Guest625101138]

Don't think this answers your question but it is something I found when I looked at squid propulsion:
http://jeb.biologists.org/cgi/content/full/208/6/1125

They may have continued this work.

Rick W.

[yacht picasso]

I saw that too... It wasn't really satisfying though!

I thought I'd ask on this forum as I know there are great minds lying around here!

[rwatson]

A form of the fictional "Red October" magnetic propulsion was actually built into a Japanese ferry in the '90 's
http://www.physicsforums.com/showthread.php?t=82886

The efficiencies of the magnetic drive were very dissappointing though.
Thee is currently some interest in the reverse process - passing water through a tunnel (tides, waves etc) with a magnetic field, and generating electrical power. Still quite low efficiencies at this stage.

[AuxiliaryComms]

Afraid I don't have much technical data for you but that is something I was pondering. I first started thinking about the idea when I saw a fin propelled kayak http://www.hobiecat.com/kayaking/models_mirage.html.

I think it would work very effectively but sorry to say I don't have a clue where to start.