|
|
Silly engine question
|
If a diesel is compression-ignition, is it theoretically possible to
have a water-compression engine?
I know you can't compress water itself, but could you compress a mixture
|
If water wasn't compressable, you'd be underwater right now...
|
of air and fine water droplets enough to heat it up and expand the steam
sufficiently to drive a piston.
|
Build yourself a PWR (1) and use both the steam expansion and the
waste heat do the work.
You can probably sell the spent fuel to a 3rd World country and make a
few quid on the side while you're at it.
(1) Pressurised Water Reactor. I've got a nice little booklet
explaining how they work and I'm sure WUN can make the parts up in his
shed.
|
Fission is old hat. Fusion is the thing these days.
Skim the head to increase the compression ratio a bit and you can turn
the water to helium and oxygen, releasing more power than it takes to
compress it in the first place, which is the key to a working engine. :-)
|
|
I did have some left over Pu
Ah yes, I gave it to an old Arab mate of mine
|
|
And if not, why not? And if not, what other 'fuel' could be substituted
for diesel oil?
|
Not sure I followed your banter, Old Chap. Where is the energy
coming from? Yes, you could probably compress air+mist until the water
turned to steam, but the only energy you'd get back out as the piston
returned is that which you put into it (as the water re-condensed), less
friction (etc.) losses.
|
|
You could, but the energy you would use in squeezing the fluid would
be more than what you would get back.
|
|
Vegetable oil from Asda, apparently
|
(I am not a physicist.... I just wondered)
|
You still need something to feed power in. I would have thought some
steam engines reclaim the steam to water and reuse that.
|
|
Neither am I, but we did engine stuff last year.
You're right that you have to add energy, it's the heat energy from
combustion that gives you the power. If you used only water, there would
only be losses[1], no gains.. So the net result would be an engine that
you'd have to drive with another engine. :)
[1] Pumping losses, friction, water phase change x 2 and so on.
|
|
The law of "conservation of energy" is your problem where water is
concerned. The energy required to compress the air/water mix would only be
equal to any energy created by the resulting steam in a perfect system. Add
in losses due to friction etc. and it would require more energy to turn the
engine that any output you might get. Any fuel would need to have its own
|
Not if he added little windmills to the top of the pistons.
|
inherent energy source e,g the heat generated when carbon-based chemicals
|
Worse than losses due to friction would be losses due to entropy.
|
burn in oxygen.
|
|
Yes...
Look up the Stirling engine.
|
|
|