Any pneumatic power tool will work OK under water and you don't even need a compressor just power it off your SCUBA cylinder. 1st stage regulator output is generally about 150psi which is OK for most pneumatic power tool. If using in sea water just wash in fresh water after use.
Now that may be an idea to power a small outboard rather than a battery drill.
So how far might you get using a diver's bottle with suitable delivery pipe and nozzle as a jet drive? Or even a petrol powered compressor? Jet drive can be more efficient than a prop.
Merely opening the valve is akin to an explosion, there would have to be a suitable regulator.If the delivery pipe was connected direct to the cylinder I think at 3000psi it would spray the water every where any you would get very wet. Connected to the 1st stage output might work but IMHO you would still need very good control of the flow. Petrol powered compressor why not use a petrol powered outboard. Drill type outboard are very low noise which is what I want in a quite anchorage
The efficiency of a jet drive comes from the fact of high water flow low pressure. The type of jet drive you propose is high pressure low flow. not so efficient.
Merely opening the valve is akin to an explosion, there would have to be a suitable regulator.
Bahh! nothing new there.....
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Yes a SCUBA tank has quite a large pressure in the bottle. Once I had one on my back in shallow water and asked a friend to check the valve was fully open. He loosened the clamp instead of the valve causing a huge leak of high pressure air. Certainly made bubbles. Quite alarming for me as I could not reach it and had to take the tank off my back. To get real eficiency from a SCUBA tank for propulsion I think you would need a pneumatic motor driving a large slow turning prop. As said it is all about coupling the energy to the water in an efficient (matching) way. olewillIf the delivery pipe was connected direct to the cylinder I think at 3000psi it would spray the water every where any you would get very wet. Connected to the 1st stage output might work but IMHO you would still need very good control of the flow. Petrol powered compressor why not use a petrol powered outboard. Drill type outboard are very low noise which is what I want in a quite anchorage
The efficiency of a jet drive comes from the fact of high water flow low pressure. The type of jet drive you propose is high pressure low flow. not so efficient.
To get real eficiency from a SCUBA tank for propulsion I think you would need a pneumatic motor driving a large slow turning prop. As said it is all about coupling the energy to the water in an efficient (matching) way. olewill