Building air pressure scooter?

[rustman]

Sounds like a cool project if it is feasible.

You might need some way to adjust the volume of the unit so its buoyancy doesn't change as you exhaust the air.

How about a propane powered unit? You could use the cylinder for combustion air and a small camping style propane cylinder (or 2?) as fuel. This might add the extra zing necessary to make it work.

(I think it is time to break out my chemistry book...)


Tom

 

[PhotoTJ]

I read somewhere that there is 1.3 million ft. lbs. of energy in a full 80, I would think someone could figure out a way to harness that.

 

[Jaap]

Yes I have seen pictures of old penumatic UW-scooters from around 1960. They looked like a tow behind scooter with a twinset on a frame connected to a simple propeller device similar to a penuamtic grinding machine except with a propeller instead of the grinding disk.

Here is a link to on version of the calculation of the energy stored in a tank: http://www.combro.co.uk/nigelh/diver/tank.html

I derived a similar calcuation calcualtion a couple of years ago when I also thought of buliding a penumatic scooter but I figured I would only really get a fraction of the power in the above calcualtion so I decided it would was easier to buy a used scooter and to tinker on with other scubaprojects...

The problem with an air powered scooter is that you would have to have a complicated machine if you want to used the explanded air for breathing, you would also loose avalible power with depth due to the increase in ambient preassure. You would also probably end up with a fairly low efficiency in turning the pressure into effective propulsion. I would say you would ned about 300 Watts of power to the prop (J/s) to get anywere and then you would problably have to spend at least as much energy on losses getting that power to the prop.

If you just want a cheap scooter I would recomend buying a used one or buildning an electric scooter. But if you take it as a challenge to have a air powered scooter, god luck! Please let us know if you get it working.

 

[boot82050]

Thanks for all reactions,

**Few years ago someone was driving a boat on such engine.Motor boats are in Bled lake forbidden so he was using compresed air. As I know 15l tank was enaugh for 1h. I'll ask for plans.**

I would veary mutch like to see these plans or hear about the concept he used.

Greetings,
j boidewitz

ps I dont kwow about the propane plan, if it is possible i like to stick to just air becouse i will just have to fill a tank of air.

 

[patymeboy]

I would like to know if it is posible to build a scooter using ion power

 

[patymeboy]

no realy are there plans for electric home built scooters anywere

 

[phunk]

If by 'ion power' you mean the ions in a battery, then yes.

If you're thinking of something along the lines of one of those ionic air purifiers that create a breeze with no moving parts, it'll never work with water.

 

[miketsp]

First thing you should do is figure out if there is enough power in the tank to make it worthwhile.

I've been thinking about it, and I don't think there is.

Here is my reasoning:

To propel a diver, the valve would most likely need to be wide open. This means that the tank would empty pretty fast.
..snip..

You're thinking purely of jet propulsion.
To use a cylinder efficiently you should think in terms of a triple expansion steam engine.
There's a nice animation about half way down this page.
http://en.wikipedia.org/wiki/Steam_engine

It should be possible get quite a high overall efficiency if you drive a large slow turning prop.

I've seen some nice models for steam that could easily be adapted to operate off a regulator IP outlet.

PS. Just been thinking about it and the real key to get efficiency would be a good variable pitch prop to ensure a more or less constant rotational speed as forward speed increases.

 

[underboats]

I use pneumatic tools frequently underwater for work and at times I have to run them with my tanks. They don't last long. For example, when drilling with a 1/2 drive drill (which would likely turn a propeller with enough thrust to push a person) I can only drill for about 5-10 minutes constant on a full 80cf tank. That's about it. Thought this may help. Chuck

 

[Where's_Wally]

I'm not sure if this device would be adaptable to underwater use...
I saw a short program on the Australian designed Di Pietro Rotary Air Engine on TV some time ago.
This design of air motor offers very high torque and low internal friction losses for outstanding efficiency.
A quick google search gave me this site - http://www.engineair.com.au/index.htm

Cheers!