Double Pendulum Power

[LibreEnergia]

Nybtorque, they "guaranteed" the wright brothers never flew.  They "guaranteed" the atom would never be split....many of the "guarantees" of the high minded, are about as useful as a wet paper sack.

PHDs.....Piled Higher and Deeper.

And where is the pile sitting?

Squarely on top of the heads of those who blindly follow them.

That, I "guarantee".



TS

Ok then, I'll do the math that shows this to be so, and post it here.

In the meantime it shouldn't be too hard to connect a small generator to this and prove me wrong, should it
Your time starts now.

[TechStuf]

LOL.  Do the math on a double pendulum.....Do ALL that math.....if you can.  Math is a tool.  And man too often employs it like a blunt instrument.   In so doing, which then, is the bigger tool?  Look at what he's done with the wheel, the wing, and his other weapons.  It is certainly no coincidence that he assumes too much and therefore misses much more.


TS

[nybtorque]

I think you are missing something. 

Sure energy is being transferred between the two pendulums and alternately causes one or the other to accelerate.  However I guarantee you the sum of all the potential and kinetic energies in the system remains constant. (or decreasing slowly due to friction).

As soon as you try to extract energy from one location the system will very quickly come to a stop as there is no excess being generated.

You're correct. Kinetic and potential energy remains constant at all times. This is accounted for by using Euler Lagrange. What you and most other seems to miss is that the pendulums actually performs real work constantly; accelerating/decelerating mass; i.e. E(work)= m * a  * s. This is the work/power I calculate in the report, and propose might be partially productive (by replacing the mass by a resistive load or pumping water). And this does not violate the energy equilibrium.


The easiest way to comprehend the function is to think of the inner pendulum mass as water which is moved back and forth and replaced by more water as we go; i.e. a pump... (as in the case of Milkovic, Feltenberger and others)


So, how is this possible? Well, I suppose it has to do with the centrifugal force acting on the fixture resulting from swinging/rotating a pendulum. This force is there at all times and is a function of speed of rotation squared. So even though the kinetic energy is constant (constant speed) of pendulum, we get a force acting on a fixture or a mass as in the case of the double pendulum. And if that mass is free to move the force will accelerate/decelerate the mass, i.e work is performed. It's the power of vibrations. (it's a little bit more complicated of course, and thats the reason for solving the Eular Lagrange equations numerically)


No doubt my model can be validated/falsified by putting a double pendulum on a generator and start swinging. I would suggest replacing as much as possible of the inner pendulum mass with a resistive load on the generator (which can be analyzed) and have a heavy enough outer pendulum to get good results. Even better if the outer pendulum can be set in rotation before the inner pendulum is released to act on the generator. 


I've used my model on the High Perfomance Double Pendulum in the youtube clip above and if we assume the pendulums mass is 1kg each and the levers are 0.4m each and that the operator sets them i motion at a 2 Hz speed from a straight up position (86 J is needed to do this). Then, if we replace the inner pendulum mass with a resistive load and assume no losses, the output would be 21 W . So within 5 seconds we have a COP>1.


Regards NT

[TechStuf]

No doubt my model can be validated/falsified by putting a double pendulum on
a generator and start swinging. I would suggest replacing as much as possible of
the inner pendulum mass with a resistive load on the generator (which can be
analyzed) and have a heavy enough outer pendulum to get good results. Even
better if the outer pendulum can be set in rotation before the inner pendulum is
released to act on the generator. 


I've used my model on the High Perfomance Double Pendulum in the youtube clip above and if we assume the pendulums mass is 1kg each and the levers are 0.4m each and that the operator sets them i motion at a 2 Hz speed from a straight up position (86 J is needed to do this). Then, if we replace the inner pendulum mass with a resistive load and assume no losses, the output would be 21 W . So within 5 seconds we have a COP>1.

In just five seconds?  That would be impressive!  Generators are now common, both linear and rotary, that are in the high nineties for efficiency.  So even at 10 seconds, or heck, say the entirety of it's cycle until dead stop.....

A "smidge" more than necessary to start all over again.

Bessler's way is cool, no doubt, but with the tech of today, following his entire path is unnecessary.


TS

[TinselKoala]

Your "model" can be falsified simply by observing that the "double pendulum", more commonly known as a Chaotic Pendulum, always comes to a stop.

Consider this: If you had really sticky bearings the thing would swing a few times and slow down and stop. Right? SO decrease the friction a little bit. Now it takes a bit longer to run down and stop. Reduce friction even more, even put it in a vacuum. It takes a bit longer... but it still stops.

Why? Because the friction eventually dissipates _all_ the energy you put in with your initial starting impulse... and nothing comes in from anywhere to replace it.

If there were _any_ excess energy in the system, by reducing friction to some arbitrarily small value... a value that is less than the magical "incoming" or created power... it would not stop swinging.  But it always does. Therefore... there is no extra energy, no excess power coming in.

ANY load you put on the system will make it come to a stop faster.


The physics simulation "Phun" or "Algodoo" even comes with a couple of Chaotic Pendulums as example scenes. If you think that the chaotic pendulum cannot be modeled mathematically... how does Phun do it, by smoke and mirrors?