Hydraulic heat engine

[brian334]

A 

[Low-Q]

A gravity powered machine is almost 100% efficient.

This topic isn't about gravity powered machines, but you are close to right. A turbine in a powerplant based on water falls (using gravity and mass), will convert 90% + of the turbines kinetic energy into electricity. However, there are loss everywhere.

[fritznien]

missed your question befor. yes you could power a steam engine on the waste heat from a gas engine.
in a car the extra equipment is too bulky and heavy for the extra output to be worth while.
in a stationary engine you would do better with a diesel engine.
of coarse if you could get a miller cycle engine you could have diesel effiecency with gas.
but it would seem the auto companys are horsepower mad and not really interested in effiecency.
just imho
fritznien

[CompuTutor]

1 - This idea is to use a looooong tube made of a non flexible material.

2 - This tube is painted black to absorb heat from the sun.

3 - Inside the tube there is water

4 - at the end of the tube there is cylinder and a piston.

I love Rube Goldberg incantation puzzles, heheh.

Let add a few things that are already used to get it to workable.

Erect a long half-circle mirrored surface the length of the pipe,
suspend the pipe at the circles center focus apex.

Now you have what people are already using to make steam.

But, lets forget that for the moment and stick with your idea
of only using water's thermal expansion ratio instead
while still retaining the state of it in the liquid form.

If the tube is large,
and you place a very small piston at both ends of it.

The load on the piston resisting can be calculated into the concept
to prevent the conversion process into steam instead to meet your criteria.

I'm sure I need not clarify that a load must be available without fail,
or all your doing is making a simple water bomb.
(YouTube a vid of a hot water heater exploding for reference !)

so, apply sunshine,
amplify sun (mirrored trough),
absorb highest Infrared possible (black),
utilize predicted coefficient of expansion for work (pistons),
repeat and rinse...

The last one is a pun actually.

Once you have said pipe and water heated/expanded,
your at the end of the recoverable work cycle now.

rinse and repeat actually translates to blocking the sun from the collector,
and cooling the work medium for another cycle.

I see this as the sticky sticking point.



Place a second larger piece of pipe around the existing first pipe,
let the outer pipe me a half circle only that has two states,
directly on top not blocking any of the sun from the collector,
and of course being on the bottom blocking the sun from the collector.

Now add a water bath from the top of the pipe
that is collected at the bottom of the pipe by the "Blocker",
and you have kept your blocker cool and have quenched the collector.

Not to mention recovered the cooling medium
which oddly enough is also the power medium.



Good start, but you need more, water is resistant to thermal change.

Don't believe me, what happens when you put a red hot metal item
into a small amount of water, it is quenched of more heat than ignorable !

Just by ratio alone the water should boil instead of course.

But it doesn't, does it.



The very medium that powers this idea of capturing expansion,
is capable of storing such a huge amount of energy that the
amount of energy to cool it outweights what you captured...

The only thing that quenches a small amount of hot water,
is a substantially larger volume of water in contact with it.

Note how I didn't say heat-exchanger,
and oxymoron in my book so far !



If you add a full factor (squared factor) of water by volume,
and you purge the heated water into that larger volume of water,
you almost instantly disperse the collected retained heat.

Water is amazing, it can incur amazing heat and absorb it
without changing It's state into the next state (gaseous in this case).

But in the same vain,
it can redistribute the heat amoungst It's "Brothers" almost instantly.

That transfer travels fasters than fart's aroma 



So, to recap:

Trough to focalize available input energy,
black pipe to absorb at most efficiency,
blocker to swing into place at end of cycle,
water to cool blocker and pipe,
100% (by volume) exchange of water
from the colector into a larger water volume.



The amount of recovered "Work" needs to pump
the volume of the heat collector pipe in full,
and quench the blocker and collector pipe,
and of course cycle to two-state blocker.

What's left over is yours to use somehow.



Did I get anything wrong ?


.

[Fester]

The "Crower six stoke engine" is such a device. It is listed on Peswiki.  http://en.wikipedia.org/wiki/Six_stroke_engine .. here as well. It is an ICE engine redesigned for 6 strokes. The water absorbs heat and converts it to steam, then is shoved out the exhaust valve. It is an awesome upgrade to the modern ICE engine.