how to make a lighter weight lift a heavier weight

[frettsy]

I refer to my thread "path of least resistance (waterwheels revisited)" - specifically the part about the oil being "forced upward through the hose".

now, my attachment. imagine the red plunger as weighing 50 pounds. below it sits 100 pounds of a fluid. the plunger is pushing down on this fluid, forcing it up through the middle of the plunger. eventually there are 100 pounds of fluid above 50 pounds of plunger and the wheel will make a half turn, resetting it. put weights on opposite sides at the extremes of the tube to make it turn that way.

now, I know this wheel won't turn "fluidly" (excuse the pun!) but it will still turn with good torque every x seconds! let's say the fluid is mercury. is this not mechanical perpetual motion? or am I misunderstanding fluid dynamics?

[AB Hammer]

frettsy

I played with a fluid wheel when I was first getting into wheels. My second design was that wheel and I still consider it one of the best ideas for a fluid wheel until a newer design I came up with a couple of months ago. Here is a link to show that wheel and a new string, on community buzz.


http://www.besslerwheel.com/forum/viewt ... 0614#50614

[frettsy]

interesting! same general concept, yes. do you think yours would work / have you tried to build it? what about mine?

I'm intrigued that you came up with a newer design also.

[greendoor]

or am I misunderstanding fluid dynamics?

I believe so.

What you are describing seems to be a hydraulic plunger. You aren't using the force of gravity to send fluid upwards, really. The force of gravity is sending the plunger downwards. This will only happen if the plunger happens to have a higher density than the fluid - therefore the end result is that the collective center of gravity of the device is going downwards.

I think you were hoping that by forcing fluid upwards, you could end up with the collective centre of gravity being higher - but it doesn't work that way.

Even for a simple solid object, the C.O.G. is an imaginary point which can be used for force calculations. In reality, the force of gravity is acting on every particle in the solid - so the C.O.G. is assumed to be the average of all these forces. It's sort of like the 3D balancing point, if you could find it.

With a fluid - the problem for calculations is that every particle can and does move. If we had enough computing power, we could model the exact movement of every particle - but that's not feasible yet. So fluid flow calculations, beyond a very simplistic format, start to require empirical formulas derived from experimental data. Hydrodynamics can be more art than science - and the science can get amazingly complicated. This is why people are still arguing about how tornados, whirlpools and other vortexes work.

I believe there is a mechanism that can provide unexplained velocity increase in fluid flow. That is the fact that every particle is already moving - just on average, all that velocity cancels out to nothing. Imagine a traffic jam, with vehicles travelling in all directions, and not getting very far. But imagine you started to provide some Order amongs the Chaos ... you could get localised streams of high flow. The power is already there - you aren't creating or forcing it - just letting it happen ...

But that's another story for another day ...

I don't believe your idea would work - but if you could explain it better I would like to consider it.

[KAS]

Frettsy,

An interesting concept but I would have to agree with Greendoor.

IMO, the plunger would be incapable of lifting more fluid weight than its own weight because the back pressure on the central tube would equalise once the the same mass /weight has been displaced (lifted).

You would think then that now that this fluid mass has be lifted to the top of the plunger, it would add to the plunger's weight and help its descent.
That would not occur however as the equal pressure would prevent it.

I like your thought processes though.

We are bound to stumble across a flaw in our current understanding of physics if we keep thinking outside the box.

Kas