Search found 107 matches

by MikeB
Mon Jul 04, 2022 8:22 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Duel IC EC engine?
Replies: 2
Views: 2807

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...
by MikeB
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: 25780

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.
by MikeB
Tue Jun 07, 2022 7:53 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Brent Van Arsdell Limited Edition restoration
Replies: 37
Views: 24299

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?
by MikeB
Thu Dec 02, 2021 9:37 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Brainstorming ideas to make more power
Replies: 6
Views: 1489

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
by MikeB
Mon Nov 01, 2021 4:36 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Tesla's "Ambient Heat Engine" Experiment
Replies: 175
Views: 191363

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...
by MikeB
Wed Oct 20, 2021 4:17 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Stirling Engine Thermodynamics
Replies: 251
Views: 104769

Re: Stirling Engine Thermodynamics

Far from being a curiosity, in my solar engine, the water vapor condenses in the power cylinder and will slow it down and then stop it. Have you tried using silica gel (or other dessicant) to dry your air? It doesn't need to be pressurised to do this, you just need a decent seal to ensure that the ...
by MikeB
Mon Oct 18, 2021 5:22 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Stirling Engine Thermodynamics
Replies: 251
Views: 104769

Re: Stirling Engine Thermodynamics

If it helps, bear in mind that some commercial Stirlings use Hydrogen or Helium as the working gas, so no mixture or water vapour effects. As far as I know, these are more efficient, but don't work substantially differently from air-based engines.
by MikeB
Fri Oct 15, 2021 8:46 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Stirling Engine Thermodynamics
Replies: 251
Views: 104769

Re: Stirling Engine Thermodynamics

Tom, I see you mention "molecular attraction" again - I'm not aware that any common gas has this property; indeed I was under the impression that a truly un-constrained gas would expand to fill whatever container it is in, regardless of temperature and pressure. Maybe I'm misunderstanding ...
by MikeB
Wed Oct 13, 2021 8:16 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Stirling Engine Thermodynamics
Replies: 251
Views: 104769

Re: Stirling Engine Thermodynamics

"Why do these various engines have heavy weights on the diaphragm "pistons"?" I suspect the main reason is that the engine is at atmospheric pressure inside, at rest. Once the engine has been 'fired up' the internal pressure will rise substantially. For a diaphragm-based engine i...
by MikeB
Tue Oct 12, 2021 5:05 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Stirling Engine Thermodynamics
Replies: 251
Views: 104769

Re: Stirling Engine Thermodynamics

I quite agree with Tom: the mass of a piston is directly _ counter _ to the ideal operation of _ any _ engine - a massless piston is always going to be better overall than a heavy one.
by MikeB
Thu Oct 07, 2021 9:10 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Programmatic control of Stirling Engines
Replies: 30
Views: 18846

Re: Programmatic control of Stirling Engines

To be positive for once - you don't need to measure temperature - you have a known (though not entirely fixed) volume of gas, so if you are able to measure the pressure then you can calculate the temperature from that. Whether pressure sensors are significantly faster than temperature sensors I have...
by MikeB
Tue Oct 05, 2021 4:50 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Programmatic control of Stirling Engines
Replies: 30
Views: 18846

Re: Programmatic control of Stirling Engines

That video of adiabatic bounce is quite a clever demonstration, but I have to point out: As you note, no REAL work is done - in our nice, perfect frictionless theoretical world, the 'piston' will continue to oscillate perpetually. But without doing any work, which is the fundamental point of any eng...
by MikeB
Wed Sep 29, 2021 9:12 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Programmatic control of Stirling Engines
Replies: 30
Views: 18846

Re: Programmatic control of Stirling Engines

Water is not energy, only a carrier of gravitational energy. The bottom video shows that that particular water wheel is rather inefficient since much of the water is being thrown clear. My problem with the experiment you describe above is that heat transfer is happening in three phases, not one: Fla...
by MikeB
Tue Sep 28, 2021 12:23 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Have you seen the dual-power stroke mod Stirling made to 1816 engine?
Replies: 11
Views: 3387

Re: Have you seen the dual-power stroke mod Stirling made to 1816 engine?

If you want to know more about how that works, look up "Parallel Motion" which was used on steam engines long before Stirling came along.
by MikeB
Mon Sep 27, 2021 5:35 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Have you seen the dual-power stroke mod Stirling made to 1816 engine?
Replies: 11
Views: 3387

Re: Have you seen the dual-power stroke mod Stirling made to 1816 engine?

Gary, sealing is actually one of the advantages of using a double-acting power piston - any leakage past the piston itself goes into the other half of the engine, rather than being vented, and then presumably leaks straight back the other way after 180 degrees. Sealing the various con-rods is an inh...