Big try at gravity wheel

[MarkE]

Since according to MH I am struggling with this could you please explain to me WHY I would use a setup where a very large percentage of the stored potential is wasted?

Why would I not use a system in line with what I posted, the one that deals with the dump loss problem.

Since the straight dump process is NOT used, why do you keep making out like it is?

Probably because you don't understand that's what you did when you defined your test case.  I am not talking about what happens when one vents to the surface.  When we first talked about that, I agreed that we would simply state that we had some unspecified means to completely recover the energy released due to the venting process.  But that is not what I have told you about multiple times now.

The loss to heat comes from where you set up the situation where you "charge" a cylinder by expelling all the water underneath it in the up position, and then you subsequently connect that first cylinder to the second cylinder that is in the down position. Energy from the first cylinder expels about half the water from beneath the second cylinder.  In that process the system loses about half the total stored energy.  The first and the second cylinder each end up with about 1/4 the energy that was originally stored in the first cylinder. 

And with that almost half the stored energy is gone forever. That's about twice as much energy as you will ever get raising the largest submerged mass that you can.  At that point, it would take lots of free energy from subsequent steps just to break even.  But none of those subsequent steps don't help either.  Even with all of the ideal constraints we placed upon the problem there are more losses in subsequent steps.  None of the subsequent steps impart an energy gain incrementally or to the entire cycle.

[MarkE]

Webby: Here is a picture that will hopefully make it very obvious to you what you have been missing about the stored energy loss that occurs during the pressure equalization phase.  I removed the piston, and made the vertical positions of the two cylinders the same for simplicity. As I explained above, once you lose the stored energy to the pressure equalization process, it leaves the system as heat, and you have to replace it before the start of the next cycle.  In the case of your sketch the energy loss is about twice as big as the useful work that eventually gets done lifting the payload mass.  It is the majority of the reason that the net efficiency is less than 1/3.

The second drawing shows the situation as you had been describing it up until the point you withdrew, with my very slight modification of the piston height.

[minnie]

   Webby,
              do a little practical experiment. Go hire a 20kw diesel pump, get a couple oF
    2000  litre tanks and some hose, put it in your garden shed and have a play. Remember
    to give it full revs.
           Say you can get plus 10% from your ZED that will mean that you've got to multiply
    the flow by more than ten times. It's quite a daunting proposition !
                             John

[MarkE]

   Webby,
              do a little practical experiment. Go hire a 20kw diesel pump, get a couple oF
    2000  litre tanks and some hose, put it in your garden shed and have a play. Remember
    to give it full revs.
           Say you can get plus 10% from your ZED that will mean that you've got to multiply
    the flow by more than ten times. It's quite a daunting proposition !
                             John

I wouldn't take that into any enclosed space smaller than an empty and large aircraft hangar.  I would also be sure to bolt the plumbing down securely.  If one were to point the hose skyward, it would make quite an impressive fountain.

[Grimer]

The Keenie.


How it works and why it works.



It is important from the outset to think in terms of the correct variable if one is to understand the way gravity is harnessed by the Keenie device.


That varible is the third derivative of position with respect to time, or jerk to give it its official shorthand name.


When a weight at the end of a radius arm is allowed to fall under gravity it is not in free fall but constrained free fall; it is not simply accelerating, it is "jerking". A weight moving at a constant angular speed around an axle is already in a state of acceleration, i.e. acceleration toward the centre, towards the axle. It is already in a 2nd derv state. Increasing the angular speed takes it into a 3rd derv  state.


The mechanism of pivot and radius arm is transducing the gravitational 2nd  derv free fall acceleration into 3rd derv, jerk.


This process in analogous the the way that an electrical transformer transduces low voltage current to a high voltage current. I've used the more general term transduce rather than the EM term to avoid the confusion that might arise if I wrote, "the pivot and radius arm is transforming the 2nd derv, acceleration, into the 3rd derv, jerk. I don't want people trying to visualise electrical currents flowing to ground. :-)


Consider now a Keenie with twelve weights distributed at 15° intervals around its circumference. This is the same distribution as the hours on a clock face and so it will be convenient to refer to the weights by their clock names. The weight initially at 3 o'clock will be the #3 weight, that at 4 o'clock the #4 weight, etc.


Initially all the radius arms are locked together and the weights are all gravitationally balanced by their opposite numbers. The #2 weight is balanced by the #8 weight, the #5 weight by the #11 weight, and so on.


Next the #3 weight is unlocked and allowed to swing down under the transduced action of gravity, to jerk down towards the #4 weight. Define clockwise(CW) jerk as positive (+ve).


The instant the #3 weight is released its opposite number, the #9 weight is no longer balanced. It also begins to jerk (-ve) down. However, because the #9 weight is locked to 5 pairs of balanced weights which it has to drag along in its fall the rate of -ve jerk will be much less for the #9 weight and its companions than the rate of +ve jerk for the #3 weight.


Another way of looking at it is to see the eleven weights as forming a compound pendulum of very slow period with the #9 weight swinging towards an eventual keeling position at 6 o'clock.


As the #9 weight slowly falls counter-clockwise(CCW) , the #4 weight will slowly jerk upwards to impact the #3 weight at some point between 3 and 4 o'clock. Assuming perfect elastic interaction both #3 and #4 will recoil and decelerate to their original start positions


Because the weights are in a closed system and no jerk energy can escape, jerk (angular momentum) is conserved. The sum of the units of CW jerk will be equal to the units of CCW jerk. Consequently there is no rotation of the wheel resulting from the elastic interaction of the weights. The impulse given to the wheel by the #3 weight is completely counteracted by the opposite impulse given to the wheel by the remaining weights.


It is very tempting to think that all one needs to harness gravity is an asymmetric gravity action. Indeed, I use to think this and pursued many false leads in this asymmetry quest. The above case is a good example of a quite extreme asymmetry and as can be seen it gets one nowhere.


Now the law of energy conservation applies to closed systems. It doesn't necessarily apply to open systems. So one needs to open up the Keenie system to allow one half of the jerk energy (the angular momentum) to escape. We need a valve which will let one half (the CCW jerk, say) out of the system and retain the other half (the CW jerk) within the system.


A one way clutch at the axle (or on a leyshaft driven by sprocket and chain in the case of the Keenie) provides just such a valve.


The clutch prevents the wheel turning CCW. Thus the effect of gravity on the unbalanced #9 is to transmit torque to the tower and hence to the ground. In other words to send CCW jerk outside the system to be lost in miniscule change in angular momentum of the earth - the same action that takes place on a much large scale with the slingshot/gravity assist technique for speeding up space vehicles.


To sum up then, #9 does not fall, #4 does not rise. All the impulse from #3 is taken up by the wheel apart from some small amount needed to assist recoil to reset the #3 somewhere between 3 and 4 o'clock and to overcome frictional losses.


Once #3 has been reset the wheel is again perfectly balanced and will continue to rotate at constant speed with the impetus given it by the #3 fall.


Quickly the #2 weight will reach 3' o'clock and the cycle will recommence with the #2 jerking towards the now fixed #3. This gives the wheel another increment of angular momentum.  The wheel will continue in this staccato fashion until it reaches equilibrium with its load plus frictional forces.