Search found 280 matches

by Bumpkin
Sun May 28, 2023 10:23 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Stephenz's work
Replies: 58
Views: 10525

Re: Stephenz's work

The Stirling bros made a pressurized double-acting engine with a segmented regenerator. If I remember the literature right, they filled-in the spaces between with broken glass to minimize dead-space. The duct itself contributes to regeneration; but since it is also a short it seems that at least in ...
by Bumpkin
Thu May 25, 2023 9:00 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: 55-gallon barrel Stirling
Replies: 22
Views: 19871

Re: 55-gallon barrel Stirling

Not the best picture, but It’ll have to do for now. I mighta finally got pictures figured out to maybe do better later. You can sorta see the door across from the chimney where a standard 4” pipe slips over. (That matches my existing shop stove.) The piston sitting on the chamber fits inside with ab...
by Bumpkin
Wed May 24, 2023 7:03 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: 55-gallon barrel Stirling
Replies: 22
Views: 19871

Re: 55-gallon barrel Stirling

VincentG, yes the tube I bought seems somewhat more plasticy than rubbery and there well might be better tubes available. I have no idea yet how it will handle various tortures, and am very dubious about the durability. That said; the 20 inch by 1.75-2.25 tube stretched tight around the 21 1/8 inch ...
by Bumpkin
Tue May 23, 2023 7:09 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Portable generator to Ringbom converstion
Replies: 32
Views: 8462

Re: Portable generator to Ringbom converstion

The tuning I’m referring to would be the force to move a certain weight and aero resistance (the displacer) at a certain speed with a certain pressure — as in how much of the pressure pulse needs to be sacrificed, (the displacement of the displacer drive) and is it a consistent value through differe...
by Bumpkin
Mon May 22, 2023 7:45 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Portable generator to Ringbom converstion
Replies: 32
Views: 8462

Re: Portable generator to Ringbom converstion

I’m thinking about doing a Ringbom for my own project, and have looked at a lot of different “expert” advice on the displacer-drive science/magic. There’s no question it works, and of course I get the pressure/displacement premise, but available tuning advice looks like mostly a bunch of buffoonery....
by Bumpkin
Mon May 22, 2023 3:39 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: 55-gallon barrel Stirling
Replies: 22
Views: 19871

Re: 55-gallon barrel Stirling

Thanks Tom. I’ll get the pictures done soon. Vince, the inflatable rolling seal might have another name. A photo won’t help much for understanding because other than the valve-stem, it’s hidden. But when you see it drawn in cross-section it’s obvious. Here’s where I first saw it: https://patents.goo...
by Bumpkin
Sun May 21, 2023 6:22 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: 55-gallon barrel Stirling
Replies: 22
Views: 19871

Re: 55-gallon barrel Stirling

Well shoot it looks like I need to shrink the pictures somehow. I have a couple here on my i-pad which I barely know how to use. I got it to replace my busted p.c. and my son was going to help me learn — just before he got married and moved out. I run chainsaws; he runs computers.

Bumpkin
by Bumpkin
Sat May 20, 2023 5:34 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: 55-gallon barrel Stirling
Replies: 22
Views: 19871

55-gallon barrel Stirling

55-gallon barrel Stirling. Years after admitting defeat on a prior attempt at a practical engine, I’ve grown foolish enough to try again. Aside from some low-tech steampunk fun, “practical” would mean cogeneration to replace my wood-burning shop stove. It would need to use standard 16 inch wood with...
by Bumpkin
Sun May 14, 2023 10:50 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Engine Pressurization
Replies: 155
Views: 32003

Re: Engine Pressurization

I’ve called the ratios different things at different times. There are times it matters and times it doesn’t. I favor Tom’s definition of compression ratio as the total system volume change; accepting that pressure is entirely different, with exchanger/regenerator effects on compression heating. Many...
by Bumpkin
Sat May 13, 2023 3:07 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: [Translating resource] 100W class LTD Stirling engine( Lesson 5-3 )
Replies: 32
Views: 9343

Re: [Translating resource] 100W class LTD Stirling engine( Lesson 5-3 )

OK Vincent. Out of respect for your demonstrated intelligence I persevered and finally interpreted. (See how respect works Matt?) And Vincent, your language might well be the way to go, but in my language — When you say 1.1 to 1, evidently that’s the same as me saying 1 to 11. As in obverse of some ...
by Bumpkin
Wed May 10, 2023 11:10 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: [Translating resource] 100W class LTD Stirling engine( Lesson 5-3 )
Replies: 32
Views: 9343

Re: [Translating resource] 100W class LTD Stirling engine( Lesson 5-3 )

OK guys. Vince, I thought you’d given one ratio: (approx 1 to 1) for compression, and then other ratios, (about 1 to 6 or 1 to 9) for the entire volume, which I can’t see the difference. And Matt, sorry I didn’t see you were talking about the spring tension external of the thermal system. I’ll go aw...
by Bumpkin
Wed May 10, 2023 10:45 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: [Translating resource] 100W class LTD Stirling engine( Lesson 5-3 )
Replies: 32
Views: 9343

Re: [Translating resource] 100W class LTD Stirling engine( Lesson 5-3 )

Yeah I could have said that better. I need to quit using cutesy mental short-hand in mixed crowds. Anyway Vincent, since you’re here and we’re talking ratios; you said in another way-back thread: “I have done further testing with the power of the piston to lift weight over simmering water and ice wi...
by Bumpkin
Mon May 08, 2023 10:15 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: Engine Pressurization
Replies: 155
Views: 32003

Re: Engine Pressurization

Well, everything about a Stirling engine is an art in compromise, so nobody’s an expert, but I’ll submit my two cents. Unless you’re running a focused high temperature, the relative size of the burner/exchangers will dwarf the actual engine, so I have to wonder at the importance of specific displace...
by Bumpkin
Sat May 06, 2023 9:22 pm
Forum: Stirling and "Hot Air" Engine Forum
Topic: [Translating resource] 100W class LTD Stirling engine( Lesson 5-3 )
Replies: 32
Views: 9343

Re: [Translating resource] 100W class LTD Stirling engine( Lesson 5-3 )

Golly Matt, you know lots of words and stuff.

Respect and thanks to gitPharm01 for this thread and your time and trouble.

Bumpkin
by Bumpkin
Sat May 06, 2023 4:51 am
Forum: Stirling and "Hot Air" Engine Forum
Topic: Pressurization
Replies: 27
Views: 26908

Re: Pressurization

Welcome to the forum stephenz. Ian used to be one of our most prolific posters but he hasn’t been here for a few years. The timing sorta matches the pandemic but? I don’t know. He’s missed.
Hope you can resolve your question.
Bumpkin