# Two separate flywheels

by D9 XTC
Tags: flywheels, separate
 P: 28 No magic? Man, that ruins everything. My initial idea was to have many flywheels made from a dense material in a relatively weightless environment (somewhere in space). Those many small flywheels are connected to one large flywheel's outer edge. The smaller wheels are spun quickly with little effort and then the bigger flywheel is spun creating artificial gravity on the smaller wheels. I was guessing that you could just turn on a generator for the smaller wheels and get energy from them and turn on a generator for the bigger wheel until it all comes to a halt. Then start it over again. I wish I could find an equation or experiment explaining why this doesn't work.
P: 28
 Quote by RonL Sounds like you read a post of mine, from a few years ago. If not, I'll say what was on my mind, might help your thoughts. If your flywheel rim has a large mass of steel, a cavity of some size, a heat element, then dumping a weight of mercury will increase kinetic energy and drive a generator as speed slows. The mercury boils and a vapor moves out to a condenser and becomes liquid again, returning to the hollow axel, the process repeats. A liter weight wheel is increased to speed, then a heavier weight wheel passes energy to the generator. A 3600 rpm flywheel might fluxuate by no more than 2 or 3 hundred rpm. Everything will be based on how long to boil whatever weight of mercury is removed at the low speed. You'll likely have to come up with something other than mercury, I know I'll never try to go anywhere with the idea, too many easier things to look at. Ron
Nope didn't see yours... couldn't sleep last night and thought this up. It's cool though that someone else has been thinking about these things too.
Mentor
P: 22,315
 Quote by D9 XTC I wish I could find an equation or experiment explaining why this doesn't work.
The equation is:

Eout = Ein

If you analyze your system correctly, you'll always end up being able to reduce the equations to that form.

The scientific principle is conservation of energy: http://en.wikipedia.org/wiki/Conservation_of_energy
 It's cool though that someone else has been thinking about these things too.
People have been trying to find perpetual motion for thousands of years. They wasted their time: it doesn't exist. Please don't waste yours!
PF Gold
P: 707
 Quote by russ_watters The inevitable miscalculation and conclusion of perpetual motion will come from assuming you can "magically" increase the mass of a flywheel somehow. Even if you're just filling a hollow flywheel with a liquid, you still have to give that fluid energy to make it spin with the flywheel. There's no magic to be had here. TANSTAAFL!
Russ, If I could give infraction points, I would, I think you deserve a couple in this case.

I did not mention perpetual motion. If you understood mechanical things better, and I could do math and use proper words, we might be a good pair to promote better energy efficiency.

What makes you think the mercury needs to be given spin energy?

If a spoke and rim flywheel is in motion, then mercury is being held in the hollow shaft, a valve release action will let a measured quantity of mercury move through the hollow spokes and at the rim the liquid will move to the outer surface of the cavity, then spread in two directions until equilazition of mass is reached. This would all take place in microseconds most likely.
I don't think your mind is seeing the small volume of space that, say 5 pounds, of mercury will require.
You may or may not know that Harley Davidson Motorcycles, have in the past and maybe still use mercury in the flywheels, but only for a balance function.

D9 XTC has not been back as far as I can tell, I hope his spirit of an enquiring mind is not diminished and that he will continue to learn how to evaluate and present his ideas.
My comments are based on the fact that his thinking is in line with what I have considered for some time, the energy balance is delicate as in all systems, the liquid/vapor/liquid process will best involve a cascade design of two or more systems. If efficiency can no longer be improved toward 100%, why is anyone here ? and why promote more education ?

P.S. Sorry if the use of gender and age implications are wrong.

Ron
 P: 1,024 The problem is that as the mercury moves outward in the wheel, the wheel spin slows down. This is true no matter what mechanism is used to move mass into the flywheel. As the wheel spin slows down, kinetic energy is actually lost.
HW Helper
P: 7,180
 Quote by RonL What makes you think the mercury needs to be given spin energy?
The mercury requires a tangental force in order to increase it's tangental speed as it moves outwards from the center of the wheel. If the mercury was just released unbounded, it would flow in a straight line, and not follow the vanes of the wheel.
 Mentor P: 22,315 Enough. Now that we know what the OP was on about, the thread is in violation of PF rules. I'm not going to allow a debunk-my-perpetual-motion-machine thread. Locked.

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