Search found 50 matches

by skyofcolorado
Tue Feb 06, 2024 12:50 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Atmospheric pressure ?
Replies: 33
Views: 2934

Re: Atmospheric pressure ?

I read that too, or at least skimmed it. My impression was that it was one of those intermediate theoretical things like irrational numbers that is conjured to solve some other problem. Could be wrong though, didn't spend much time on it. Even so, everything he has mentioned so far is explained by c...
by skyofcolorado
Tue Feb 06, 2024 8:39 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Atmospheric pressure ?
Replies: 33
Views: 2934

Re: Atmospheric pressure ?

Already done, here's an old Vertasium video. 55gal toward the end. 25mS to crush. Still seems completely consistent with combined gas law and the expected phase changes. Further, it might not be as impressive at my altitude of 1700 meters. Better at sea level where the pressure is higher. https://ww...
by skyofcolorado
Tue Feb 06, 2024 8:09 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Atmospheric pressure ?
Replies: 33
Views: 2934

Re: Atmospheric pressure ?

Well, honestly, that sounds kind of like a rather gradually process, whereas the 55 gallon drum demonstration is popular, I think, mainly for its shock value. The drum implosion is like a gunshot. Blink and you'll miss it. BAM!!? A matter of perspective I suppose. I've had a global shutter high-spe...
by skyofcolorado
Mon Feb 05, 2024 2:32 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Atmospheric pressure ?
Replies: 33
Views: 2934

Re: Atmospheric pressure ?

I'm thinking of a piston returning to TDC "by atmospheric pressure" without any apparent means for heat removal. I think these are two completely and totally unrelated matters, which may be part of the confusion. The power piston in a gamma engine has zero role in heat transfer/removal. I...
by skyofcolorado
Mon Feb 05, 2024 2:05 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Atmospheric pressure ?
Replies: 33
Views: 2934

Re: Atmospheric pressure ?

Similarly, a 55 gallon drum suddenly collapsed when filled with steam, then cooled. How does the steam condense in a vacuum that isn't a vacuum until the steam condenses but if water were to condense it would boil and produce cold steam. The parameters are changing as the event transpires. It start...
by skyofcolorado
Mon Feb 05, 2024 1:09 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Gigantic LTD
Replies: 2
Views: 923

Re: Gigantic LTD

Instead of lifting the entire weight of the displacer I never really understood the focus on the weight or mass of the displacer, piston, or other moving parts. What am I missing? I get friction being an issue of course, but the mass of the moving components should be nulled out by the counterbalan...
by skyofcolorado
Mon Feb 05, 2024 11:28 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Atmospheric pressure ?
Replies: 33
Views: 2934

Re: Atmospheric pressure ?

If it would help you, design an experiment that I can reproduce and I'll film it in the chamber. It's 28cm deep and 29cm diameter.
by skyofcolorado
Mon Feb 05, 2024 11:20 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Atmospheric pressure ?
Replies: 33
Views: 2934

Re: Atmospheric pressure ?

Or, what if we were to do the steam condensing in a can experiment, but before the can can cool and collapse, put it inside a vacuum chamber. Would the "attractive" force of the condensing steam collapse the can without the external atmospheric pressure? No. No collapse if done under vacu...
by skyofcolorado
Mon Feb 05, 2024 8:24 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Atmospheric pressure ?
Replies: 33
Views: 2934

Re: Atmospheric pressure ?

... Or will the egg explode? Would it get pulled apparent and 1/2 the egg end up in each bottle? Having done lots of vacuum chamber experiments, my guess would be that if it's a good enough vacuum, the water in the egg would boil at room temperature - as water does in a vacuum, and the egg would lo...
by skyofcolorado
Fri Dec 29, 2023 7:36 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: 60L drum medium temp Gamma build
Replies: 42
Views: 15360

Re: 60L drum medium temp Gamma build

I'm kind of worried about using pink foam board though. That stuff burns like gasoline and melts into a black goo that can be hard to put out of it catches fire, and it catches fire pretty easy. There are different kinds of foam board, some that burn, others not so much. Could be additives to meet ...
by skyofcolorado
Fri Dec 29, 2023 7:15 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: 60L drum medium temp Gamma build
Replies: 42
Views: 15360

Re: 60L drum medium temp Gamma build

Marvelous progress, I bet it feels good to have some parts coming together. It's certainly motivational for me to see it progressing. Looks like a steel drum, but aluminum cooling fins? How did you weld those? Does that seem like enough cooling, or will you be adding more fins? How will you concentr...
by skyofcolorado
Wed Oct 11, 2023 2:07 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: ÖkoFEN Stirling CHP available in the US ???
Replies: 10
Views: 6286

Re: ÖkoFEN Stirling CHP available in the US ???

And PV systems don't use tracking? I can hardly think of anything simpler than tracking the sun. At the current price point of PV, we just add more panels to fixed mounts to make up for the slight gain in Wh/day you would get with tracking. It's really not that much due to atmospheric effects at th...
by skyofcolorado
Tue Oct 10, 2023 6:49 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: ÖkoFEN Stirling CHP available in the US ???
Replies: 10
Views: 6286

Re: ÖkoFEN Stirling CHP available in the US ???

Talking about maintainance? The things could run for 30 years without being touched, running on some space probe till they left the solar system or beyond. I was talking about the tracking mechanism. The engines are obviously solid, but they need tracking for solar, and everyone that's dealt with t...
by skyofcolorado
Tue Oct 10, 2023 3:20 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: ÖkoFEN Stirling CHP available in the US ???
Replies: 10
Views: 6286

Re: ÖkoFEN Stirling CHP available in the US ???

You know, I'm a real advocate of Stirling engines for niche applications, but I just don't see solar being one of them unless you're in space. Look at the engineering, materials, complexity of mechanisms, maintenance of the tracking system, etc. of that installation. Compare to commonly available an...
by skyofcolorado
Sat Apr 29, 2023 8:55 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: High temperature displacer
Replies: 191
Views: 81093

Re: High temperature displacer

The rapidset CSA mix from home Depot is my go-to for so many little structural objects (like my current stirling engine - 90% cement.) Relatively inexpensive vs. resins, super fast and hard, plays well with high-detail silicone molds, takes fibers for extra durability, easy to color, stain and seal....