compressed air engine powering a air compressor

[59flatbedford]

ok this is a little out there but i was thinking this morning and theoretically could you have a compressed air engine hooked up to and driving an air compressor that in turn provided the air to run the engine, an engine powering itself. if the air compressor could put out the same or more air than the engine would use at any given rpm the motor could essentially run forever on its own energy right. this makes sense in my head but im sure it dont work this way or else there would be examples of this in the real world. just a crazy thought and since im new to air engines and am no where near a engineer of any sorts, although i am going to college next fall for mechanical engineering, thought i would throw this out there to ponder.

 

[ksouers]

That's called perpetual motion. It doesn't work. Friction and inefficiencies will always cause it to stop.
There are always losses in any system, that's why you have to keep replenishing the energy.

 

[Mainer]

You're kidding, right? If not...review the laws of thermodynamics, especially the one that can be summed up as, "You always lose."

 

[Kermit]

;D Trying to do so is an excellent way of decreasing all the torque sucking problems in your design, but you will still lose some of the energy along the way so you just can't self run a motor from a generator. If you get it as perfect as possible it might run for a few moments but at ever decreasing speed...

This is also called HIGH efficency designing. ;D It is a worthy goal.

 

[rake60]

Perpetual motion has never been achieved but there are still
research groups around the world trying to find a way.
Keep thinking.

Rick

 

[Noitoen]

That's called perpetual motion. It doesn't work. Friction and inefficiencies will always cause it to stop.
There are always losses in any system, that's why you have to keep replenishing the energy.

The guys at steorn say it's possible. Rof} Rof} Check this out [ame]http://www.youtube.com/watch?v=us7YB7eiOeQ[/ame]

 

[rake60]

In the 17th century somebody came up with a design for a perpetual
water driven gain mill.

It didn't work but it was an interesting idea.

Here's a good related link: http://www.lhup.edu/~dsimanek/museum/thinking.htm#masstransfer
Thanks for the thread 59flatbedford. Keep US thinking as well!

Rick

 

[ChooChooMike]

The guys at steorn say it's possible. Rof} Rof}

Oh boy, 10 minutes of a ball going around. Thankfully there's a FF button there. :

 

[59flatbedford]

well yea obviously in this world of friction it most likely would never be possible and one leak in the whole system and its sol hence the "theoretical" but would be interesting to see even if it was just a supplement pump to the main compressor pump. and thanks for that pic of the grain mill it always amazes me to see the wonders that the people of the past where able to come up with.

 

[rake60]

The original design of that grain mill's recirculating water feed system was from
some amateur engineer named Leonardo da Vinci.
That idiot believed it possible for man to fly and drew up plans for flying
machines! How crazy is that?

In his day, many of his ideas were written off as being silly
and inspired a lot of laughs from the naysayers.
Many of those ideas were just ahead of their time...

Rick

 

[Captain Jerry]

I built one of those engine/compressor combos once. I couldn't figure out how to get it started.

:-\

Jerry

 

[gilessim]

interesting subject there, also known as an "unbalanced force", check out this ;

http://www.besslerwheel.com/

Giles

 

[mako20]

You could try running it at absolute zero.

 

[shred]

In one of my X-mas books is an interesting "perpetual" motion machine with plans.

It's a fake, but a tricky one to detect.. and it works on the 'unbalanced wheel' concept.. and includes an air compressor

English Mechanics magazine, 1933.. or Workshop Masters #11

 

[bob ward]

When I was a kid I came up with this idea of having a windmill at the front of my push bike, driving a shaft to the rear of the bike with a propellor mounted on said shaft.

The idea was that as I pedaled along the windmill would drive the propellor which would make the bike go faster which would make the windmill turn faster etc. My main concern was whether the bike brakes would be adequate to restrain the beast once I got to school.

I spent a fair bit of time trying to make the idea work properly but I never got there. Maybe if I had had proper bearings and some decent shafting rather than a broom handle passing through bent up wire coat hangers. Or perhaps I had the windmill/propellor ratio wrong, I hadn't done algebra by then.

 

[tel]

;D ;D ;D

 

[Bluechip]

Bob,

You should have tried a Flettner Rotor. You'd probably still be going now

Here's your Algebra bit to go with it ...

http://www.berr.gov.uk/files/file17770.pdf

Dave

 

[Cliff]

When I was a kid back in the 60's I had the same idea about a compressor driving a compressor but every time I tried to say anything about it was referred to as foolishness so I finally put it in the back of my mind and forgot about it but I don't think it is impossible if you can over come friction. Cliff.

 

[cfellows]

The thing is, if you completely got rid of all friction, you wouldn't need the compressor. Just give the engine a flip and it would run forever.

Chuck

 

[Metal Mickey]

59flatbedford, don't ever be put off asking questions! It was a good thought and I am sure you'll enjoy your course. Well done!