Barton Evaporative Engine

[fullofhotair]

I know this isnt the barton evaporative engine cycle ,but would it work?


I'll give it a go.It is a adiabatic expansion cycle.Adiabatic meaning not lossing or gaining heat.Think of a steam engine, a cyclinder with a sealed piston inside connected to a rod .The rod is connected to a fly wheel.The weight of the fly wheel continues motion after the power stroke.The momentum has driven the piston to the bottom of the cyclinder.This has compressed the air and heated it.Then an atomized water spray is injected.This combination causes the mist to evaporate and expand.As the water vapor expands it now pushes the piston up[power stroke] as the moist air expands it absorbs heat=latent cooling.When the piston is close to the top a oneway valve opens and the gas escapes then the valve closes.Right after it starts back down pushed by the rod connected to the spinning fly wheel,another oneway valve opens in the opposite direction sucking hot air from outside then closes.This air has been preheated by a solar collector, waste heat or any other source.These engines have the advantage of being able to use low grade heat like passive solar.they do need dry air or a dehumidifier to condition the moist air first.For hot humid locations a liquid desiccant would work well

Read more: http://wiki.answers.com/Q/How_does_the_ ... z22gT7ye3N

[Bumpkin]

"This has compressed the air and heated it. Then an atomized water spray is injected. This combination causes the mist to evaporate and expand."

I don't think so - but I'd welcome any new understanding. You can't steam water by injecting it into compression-heated air, because the pressure also raises the flash point.

Evaporative coolers are very effective in hot dry climates. As I understand it, evaporating water doesn't expand or steam, it becomes a saturated element of the air. But it still takes energy to change phase from liquid to gas - energy absorbed from heat in the air. So evaporation cools the air and power is available in a vacuum-engine way, but is limited by the differing dew-points or flash-points of differing pressures. That Barton process is interesting. Bumpkin

[aero]

The Barton engine would only work if the air in the cylinder was really hot otherwise spraying water in would chill the air stopping the piston sucking up the heat of evaporation, as Bumpkin explains like an evaporation chiller cooler they use on the football players on the bench. Water injection was used extensively on the thousand horsepower piston engines in WW2 to prevent ping and is used on diesel engines to cool the cylinders and prevent pre-ignition before top dead center where you have ample heat to evaporate the water. Evaporation chillers work nicely on the COLD end of a Stirling.

[fullofhotair]

Isnt the Barton evaprotive engine
www.sunoba.com.au/evap%20engine%20intro.htm
Isnt the Barton evaprotive engine similar to the Newcomen steam engine but just using the vacuum end of the cycle?Couldnt a simple model be built comparable to the pop can stirlings?Do you need the 2 opposing pistons or would a flywheel carry it through the cycle?Its an open cycle couldnt you just use the hot gas from a candle or alcohol stove directly sucked in the piston .As the piston lifts off the bottom the water mist is released on the top side(the cold end).This could be triggered by a timing crankshaft like is connected to the displacer on a stirling.The vacuum is the power stroke.The mister could just be a pressurized spray bottle.How would you release the used gas when it reaches the top of the cold end and suck in the new hot working gas?At this point its just kind of a mental exercise but if the questions can be answered or refuted I wouldnt be surprised if someone here built one.There is video at sunoba site and an animation at the wiki newcomen page.

[Ian S C]

I think this subject has come up before, someone was arguing for perpetual motion, and could not understand that his proposal would take more energy to make it run than it could produce. But every idea should be proved yes or no, either by theory, or experiment. Ian S C

[fullofhotair]

I think people underestimate the power of rapid condensation. Colapsing Soda Can on You Tube - www.youtube.com/watch?v=skhSfFz28g0
Now my question is would that can colapse if it was heated to the same temperature and an atomized mist injected or is it the steam that is already in the can? If its just the steam condensing then why arent piston steam engines using that extra force? I can see why they didnt use it in the past because iron or steel are good heat conductors.We now have strong materials that are good insulators.Iam not trying to upset or argue with anyone, just learn.If the Barton engine isnt using the colapsing can scenario what is actually taking place?.They claim efficiencies equal to the rankine cycle for the Barton evaporative engine.

[Bumpkin]

I don't think there's any steam to condense. I believe the Barton's operation as a piston engine resembles a flame-gulper in principle: In an oversimplification, the flame-gulper takes in a burning gas mix that consumes itself to create a vacuum; the Barton engine takes in hot dry air which is cooled by evaporation to create a vacuum. The Barton isn't a violation of physics, but there's not much energy available - certainly less than the flame-gulper, which itself has nominal power to get out of its own way. As for making a model, you could possibly just copy a flame-gulper design and add a water mister. I think the intake timing of those engines usually closes before the end of the stroke, which would produce vacuum at the right time to (maybe?) pull the mist in without any further trickery. Preheating might be necessary, but I wouldn't say it's impossible to make an evaporative engine work with direct intake from a hot dry day. It would need massive displacement to be useful, but who knows? So many possibilities, so little time. Bumpkin

[Ian S C]

This cycle reminds me of the very early steam engines, with them the boiler pressure was about 5psi, the steam was injected into the cylinder at bottom of its stroke, cold water was poured over the top of the cylinder to cool it, as the steam cooled the atmopheric pressure pushed the piston up, the weight of the beam(and pump rod, these were non-rotative engines), took the piston down again. Then (Watt or one of the other steam engineers)got the bright idea that if you upped the steam pressure, and injected the steam at the top of the stroke, you would get much more power, using much less fuel and water. Ian S C

[Tom Booth]

As a kid, my brothers an I used to put a little water in an empty 1 gallon vermont maple syrup can. With five children, my family went through a lot of maple syrup.

Then put it on the stove until the water inside boiled and steam came out, then we would screw on the top and dunk it in ice water and it would implode, as if it had been run over by a truck probably some such science experiment my older brothers learned at school.

More recently I was wondering if a flame licker engine could be modified to take advantage of this change of state.

Possibly heat up a "Regenerator" in a glass tube, so the engine draws a spray of water through the hot steel wool as the engine is drawing in air/heat/steam.

Probably it would get waterlogged, from all the condensation inside eventually though.