Stirlingengineforum.com

Just to be clear, atmospheric pressure is at the horizontal line. Compress_20240429_015658_8970.jpg The piston returns 99% of the way by mother nature's "free lunch" as you call it. Actually all the way. The piston has momentum. That too comes from atmospheric pressure. You have head of Ne...

... You seem to be always dismissing the backwork of compression as if the ambient compression of your LTD is a free lunch thanks to Mother Nature... I don't think LTD's are functionally any different than so-called "thermoacoustic" or lamina flow, thermal lag. The pistons return EASILY, ...

.... Good catch Tom on the animation where most of the ideal constant volume transfers are lost amidst real out-of-phase pistons. I'm not sure what I caught that is described by what you just said. "Ideal constant volume transfers"? "Lost"? I can't say I caught that, really, as ...

I may be wrong, but given that pressure and temperature are more or less associated, I can't help but wonder how the working fluid falls, and stays, so far BELOW atmospheric pressure, all the way back to TDC. Resize_20240428_230612_2510.jpg A drop in pressure down to around atmosphere, can be attrib...

Start out with three hundred Homunculus's, little humans, inside an engine pushing out. Add one hundred more. As they push out they get converted to work. After 100 have been converted to work expansion stops. Pushing the piston back in using the work that came out, causes 100 Homunculus's to reapp...

Only observing animations your "differential leverage" observation makes sense in that after the hot piston moves back exposing the hot sides of the hot cylinder, (assuming there is actually a heated hot cylinder as in most animations, Matt has said this is not usually the case, but it's h...

If we assume from all this then, that Tesla's proposed "self acting engine" that runs on ambient heat due to the presence of a "perpetual" cold, how would such an engine be optimized? Compress_20240427_222542_2565.jpg Well, we need very good insulation to protect the ice from the...

Taking this sample problem: T1=400°K T2=300°K efficiency = 1-300/400 = 1/4 = 25% https://www.toppr.com/ask/question/the-source-and-sink-temperatures-of-a-carnot-engine-are-400k-and-300-k-respectively/ That is fine. I agree with it! The question is 25% of what? 25% of T1, all the heat down to absolut...

What happens if active cooling is supplied? That does not increase the "flow of heat through the engine" it just lowers the platform. Lowers the "equilibrium" plane where energy inside the engine is balanced by energy outside. Now if we supply the same 100 joules above ambient, t...

I actually very much like "fools" effort to normalize all the variables so that a 1 degree rise in temperature equals, or can be represented by one joule of heat. Nothing wrong with that. The problem stems from the disparity between the old theory of heat as caloric a conserved "fluid...

Easy, tiger. Just because the engine is only making use of the pressure differentials available between 300K and 400K, doesn't mean a calculation involving the total internal energy of the working fluid, including the 'unused' energy from 0-300K can't be valid. Tom has 20 apples. He eats five and l...

The steam engine running on the Rankin cycle, with latent heat to reject, is even less efficient than a Carnot or Stirling. Can't attribute the theory to that. It would even be less efficient yet if the latent heat were left in during compression. Back work is inevitable. Have you read the lectures...

Well, 0° K on a PV diagram, I think, is your interpretation. A PV diagram is Pressure Volume. So "all the way down" would represent 0°K ? Temperature is represented by curves. At any rate the actual States of the engine plotted on the diagram don't go "all the way down" to zero d...

Tom you are too combative to respond. Me combative? Just telling it like I see it. "Importing all the internal energy down to absolute zero" is nonsense, bordering on delusional IMO. Where you guys come up with this crazy stuff is anybody's guess. As Professor Richard Feynman said, "...

How is Qhz the "maximum"? Qhz is not the "heat" supplied. Qhz is Qcz , the pre-existing environment in thermal equilibrium before any heat is supplied, added or taken in by the engine. Plus the few additional joules actually supplied. As you say: "the cycle starts at Qcz, (...