Search found 102 matches
- Wed Aug 09, 2023 4:39 am
- Forum: Stirling and "Hot Air" Engine Forum
- Topic: The Carnot efficiency problem
- Replies: 258
- Views: 118716
Re: The Carnot efficiency problem
Tom, The simple point is that we all know that you cannot get power out of a machine without putting energy in. We can all discuss perpetual-motion as part of understanding the operation of a "perfect" Stirling engine, ie one with zero friction, but "free energy" is a whole 'noth...
- Tue Aug 08, 2023 4:25 am
- Forum: Stirling and "Hot Air" Engine Forum
- Topic: The Carnot efficiency problem
- Replies: 258
- Views: 118716
- Fri Aug 04, 2023 4:08 am
- Forum: Stirling and "Hot Air" Engine Forum
- Topic: The Carnot efficiency problem
- Replies: 258
- Views: 118716
Re: The Carnot efficiency problem
Tom, It seems to me that a very simple experiment is possible, and hopefully useful, which is to de-couple the displacer from the piston of a suitable engine - probably by connecting a second flywheel. My question was meant to be somewhat rhetorical, and based round logical thought experiments but p...
- Thu Aug 03, 2023 7:14 am
- Forum: Stirling and "Hot Air" Engine Forum
- Topic: The Carnot efficiency problem
- Replies: 258
- Views: 118716
Re: The Carnot efficiency problem
Goofy, What is the point of the displacer? Is it needed?
- Thu Aug 03, 2023 2:28 am
- Forum: Stirling and "Hot Air" Engine Forum
- Topic: The Carnot efficiency problem
- Replies: 258
- Views: 118716
Re: The Carnot efficiency problem
Goofy - the problem is this: If for a moment, we ignore the "work done" on/by the piston, then what keeps the motor running? The simple answer is the alternating change in pressure of the working gas. What causes that change in pressure? The smaller reason is change of volume from the pist...
- Thu Jul 20, 2023 11:21 am
- Forum: Stirling and "Hot Air" Engine Forum
- Topic: The Carnot efficiency problem
- Replies: 258
- Views: 118716
Re: The Carnot efficiency problem
The "Cloud in a bottle" demo - it's not really an experiment - is largely a demonstration of the rather surprising properties of humidity and vapour saturation, not of temperature directly. The cloud forms because the loss of pressure moves the dew-point. (I've seen it done much more impre...
- Mon Jul 17, 2023 7:01 am
- Forum: Stirling and "Hot Air" Engine Forum
- Topic: The Carnot efficiency problem
- Replies: 258
- Views: 118716
Re: The Carnot efficiency problem
Tom,
The problem with treating ambient as being equivalent to zero, is 'pressure' doesn't agree with that at all - gas pressure at 300K is 75% of that at 400K (for the same volume) ...
The problem with treating ambient as being equivalent to zero, is 'pressure' doesn't agree with that at all - gas pressure at 300K is 75% of that at 400K (for the same volume) ...
- Fri Jul 07, 2023 9:20 am
- Forum: Stirling and "Hot Air" Engine Forum
- Topic: Ambient heat engine design theory
- Replies: 8
- Views: 2313
Re: Ambient heat engine design theory
What's the comment on the left, about "cold steam" all about?
- Fri Jun 23, 2023 12:58 am
- Forum: Stirling and "Hot Air" Engine Forum
- Topic: Carnot reveal for Tom
- Replies: 162
- Views: 173127
Re: Carnot reveal for Tom
Firstly - proving that Carnot is wrong is actually easier than proving it is correct - essentially Tom is claiming that Reindeer CAN fly, which is easy to prove (if true) - just need to see one flying, and/or show appropriate Maths. Secondly though, you I need to support part of (what I understand) ...
- Mon Jul 04, 2022 9:06 am
- Forum: Stirling and "Hot Air" Engine Forum
- Topic: Stirling "Hit 'N' Miss" Hot air engine
- Replies: 46
- Views: 15755
Re: Stirling "Hit 'N' Miss" Hot air engine
For the two-stroke engines, would it be possible to invert them, and effectively have a sump above the pistons?
- Mon Jul 04, 2022 8:22 am
- Forum: Stirling and "Hot Air" Engine Forum
- Topic: Duel IC EC engine?
- Replies: 2
- Views: 2713
Re: Duel IC EC engine?
What that diagram doesn't make clear, is what the two parts of the engine are meant to do? If they are intended to be linked to a common shaft, then I would suggest that that is a very bad idea - allegedly simply linking two IC engines to the same shaft is a very big deal, so getting the power outpu...
- Tue Jun 21, 2022 8:22 am
- Forum: Stirling and "Hot Air" Engine Forum
- Topic: Looking for diagram of a simple and effective Stirling heatpump
- Replies: 18
- Views: 25608
Re: Looking for diagram of a simple and effective Stirling heatpump
If I may expand slightly on an earlier comment or two - a "Stirling Heat Pump" is a fairly well-known device, though rarely needed/built by amateurs, I suspect! As noted, it needs something to drive it, which can just as easily be a "Stirling Engine" as anything else.
- Tue Jun 07, 2022 7:53 am
- Forum: Stirling and "Hot Air" Engine Forum
- Topic: Brent Van Arsdell Limited Edition restoration
- Replies: 37
- Views: 24067
Re: Brent Van Arsdell Limited Edition restoration
May I suggest cutting a larger disc for the base, then those supports can still be used, but twisted at an angle to match?
- Thu Dec 02, 2021 9:37 am
- Forum: Stirling and "Hot Air" Engine Forum
- Topic: Brainstorming ideas to make more power
- Replies: 6
- Views: 1422
Re: Brainstorming ideas to make more power
If valves and such are involved, you need to be looking at some of the relatives to the Stirlings, such as the Manson Engine
- Mon Nov 01, 2021 4:36 am
- Forum: Stirling and "Hot Air" Engine Forum
- Topic: Tesla's "Ambient Heat Engine" Experiment
- Replies: 175
- Views: 182684
Re: Tesla's "Ambient Heat Engine" Experiment
Close, but not quite - the retro-reflective materials that they use on road signs etc rely on hemi-spheres, not full-spheres - like having a million tiny parabolic satellite dishes. Even then, only about 50% of them point in the right direction, and since they aren't parabolic, those that do reflect...