Pressure based idea

[Gravitator]

Hi all!


God this is difficult but here is an other try, this time based on pressure.
There is one big questions that I couldn't figure out by myself or neither I didn't find any answers from web.
So I'd like to know if anyone of you can answer me.


The big question

How does the hydrostatic pressure behave in the situation I have draw ? I don't think it will disappear and
I don't think that in pool there are different pressures depending if you are under the pressure tank
or beside the pressure tank under water.


If I'm right and there is a hydrostatic pressure difference under the pressure tank depending if you are
under the water level of the pool (lower pressure) or above the water level of the pool in the pressure tank (higher pressure)
then I see the systems behaviour at different phases like this. Now I'd like to know where I have made
mistakes in my thinking - or have I


Air tank pressure ?

Air tank have equal pressure on top and bottom if the hydrostatic pressure of air is not counted.
This pressure is equal to hydrostatic pressure of water at the bottom of air tank.


What happens when the air pressure tank fills the piston with air?

When air moves from air tank to piston (because of pressure) this will lower the pressure in air tank.
This means that the water level at the bottom of air tank will rise. But at same time the volume of piston size
will increase. So what I think is that the pools water level don't change. Does this mean that we get buoyancy
for free by using pressure difference ?


What happens when the piston filled with air moves from pool to pressure tank?

From pools water level point of view this means that the water level will get lower. But at the same time
the same amount of water will come from pressure tank. So the water level in pool don't change.


What happens when the pressure tank pushes the air back to air tank ?

This will lower the water level at the top of pressure tank. But at the same time the outer air pressure
will "push" the same amount of water to pressure tank. This will not lower the pools water level because
at the same time the air tanks pressure will increase which will push the water at the bottom of air tank
lower.


So for me it looks like we can get buoyancy for free. Or actually it is not free. The required energy to do
all these thing is at the end retrieved from outer air pressure.



So now we have buoyancy and this buoyancy should move the machine. This means that buoyancy should be greater
than forces against buoyancy: friction (piston, rollers, water resistance) and opening and closing the air tank connections.

Because I don't have any clue how much the this may cost or how much it is possible to reduce these, I don't start guessing.
Basically I think the bigger piston the more buoyancy.

An other big question is how fast the pistons will be filled with water or air. I guess this depends on
pistons size, friction and size of air tank connections tubes. And this requires much more knowledge of hydraulics
that I currently have


On thing is that the pressure in air tank will slowly decrease. How fast this happens is a mystery to me.


BR,
Gravitator

[truth]

Have you read about the hydrostatic paradox?

Apart from the other problems in your drawing, everything will just reach equilibrium and stay that way.

Is gravity a conservative force?  Can it be more?

[hansvonlieven]

G'day Gravitator,

How will you keep the water from boiling? If you maintain a vacuum above the water the water will boil at ambient temperatures and your vacuum pumps will have to work overtime.

Just another little snag along the way. Read up on vapour pressure.

Hans von Lieven

[tbird]

hans

his 1st drawing looks more like a chicken water dispenser (with stuff inside).  no vaccum pump is needed to keep the water in the upper part.  as long as the water is above the lip of the up-side-down cylinder (jar), no water will come out.

i'm not sure, but i would say the water is hanging from the top (with help from atmosphere pushing on surrounding outside water) as much as supported from the bottom.  if so, then the upper water  won't exert as much weight as if it were open to atmosphere.

i may not have said that exactly right, but i think you can.

tom

[truth]

@ tbird,

The weight of the water in the top tank would all be on whatever supports that tank at the bottom.

@ all

Would the pressure in the top tank be negative? Is the water pressing down or pulling on the water above it?

There is pressure available at the bottom of a water column, but if you use any of it, then the water that moves must be re-lifted in order to reset the potential energy available.