Stirling engines

[machinemaker]

Anyone out there with experience with stirling engines. I have an application where I have a waste stream of heat and was curious about using it to generate power. I could use some advice as to books and references.

[kawalekm]

Hello Kent
I myself don't know much about Steriling engines, but I do know that a new experimental solar/sterling engine power plant is being built in the Mojave desert. Sunlight is focused on the heat exchanger of the sterling engine, which drives a 1-2Kw generator. An individual unit looks a lot like a commerciall sized satelite dish with the sterling engine suspended out in front. A several hundred collector/engine array will generate peak power in the megawatt range and will be 3-4 times more efficient than photoelectric panels. I believe that it is supossed to go on-line in 2008.
Michael

[machinemaker]

Thanks. I'm building a secondary combustion wood burner for heating several hundred gallons of water and want to tap the exhaust heat before it leaves the flue. I thought that a stirling engine could run an axial alternator and act to help charge a bank of batteries to run some dc pumps.
kent

[kleven626]

I have been working and running stirling engines for a few years. the ones that i get to play with are from the late 1800's+. they don't produce more than .5 HP. I was going to see if i could hook an alternator to one and get it to produce something. i'll keep you posted. i will try and post some pics.

[kleven626]

can anyone tell me how to post pictures?

[machinemaker]

kleven626
on posting photos: put your photos on a free server like photo bucket and then copy and paste the link into your message. Sorry to take so long to reply, my employer is working us 7 days a week for the last month and I have not taken the effort to get online as much.
kent

[carugoman]

here's a link, I think of some inept engineering grad/undergrad students(with limited shop skills), attempting to make stirling engines: http://xenotechresearch.com/xsolar.htm I was doing a search on "Fresnel Lenses" and "Archimedes Fire Machine". Those two items may be of interest since, I had started the original research over 12 years ago when there was no way to "google it" since google didn't exist back in the "olden days? :D

[Steve_L]

I like these books:
http://www.lindsaybks.com/

Here's one on a two cycle stirling engine
http://www.lindsaybks.com/dgjp/djgbk/twocyl/index.html

In theory, Stirling engines are as efficient as the Carnot cycle, which is as efficient as you get without violating the laws of thermodynamics. But theory says that the work energy that goes into the Stirling cycle is equivalent to the heat energy, which isn't EXACTLY true. That machanical work energy comes at a cost.

For this reason, engineers like steam engines. In a steam engine, you pump a small volume of water and let the heat energy do the work in expanding it. Less efficient in physics theory, more efficient in economic theory.

Unless, of course, you're talking about using energy from a heat source not much greater in temperature than your heat sink, and you don't mind low power outputs.

[gunsmoke]

Some years ago I had read in a monthly tabloid by the name of FARM SHOW That the United States Air Force had converted a substanial number of Dodge Pickup Trucks to Stirling power. The only negative comment was that it took about 2 minutes for the engine to heat up but that the engine was VERY Torquey and there was no discernable difference in drivability. There was no disussion of gearing or transmission modifications.

I think the article or an abstract of it is available on the Internet somewhere, probably.

[gunsmoke]

Some years ago I had read in a monthly tabloid by the name of FARM SHOW That the United States Air Force had converted a substanial number of Dodge Pickup Trucks to Stirling power. The only negative comment was that it took about 2 minutes for the engine to heat up but that the engine was VERY Torquey and there was no discernable difference in drivability. There was no disussion of gearing or transmission modifications.

I think the article or an abstract of it is available on the Internet somewhere, probably.

LINK TO ARTICLE: http://www.farmshow.com/index/detail.asp?article_id=3165124&source=FARMSHOW

Is there a way to edit a post you have already posted? i could not find that feature so I posted again.

[sm0kin]

there have been submarines built using Stirling engines.

[PaulNKS]

Is there a way to edit a post you have already posted? i could not find that feature so I posted again.

There is, after a certain time or number of posts or something. lol...

[Curbie]

Anyone out there with experience with stirling engines. I have an application where I have a waste stream of heat and was curious about using it to generate power. I could use some advice as to books and references.

Stiriling engines function by temperature differential, gas law, http://en.wikipedia.org/wiki/Ideal_gas_law

Here’s the largest hobbyist group.
http://www.sesusa.org/

Here’s a model hobbyist group.
http://www.bekkoame.ne.jp/~khirata/

I have spread-sheets on both gas law and Stiriling engines if you’re interested.

My conclusions (for what their worth) is that solving material design problems is possible, but only really practical (cost effective) on an industrial scale.

An example of this, the only small-scale commercial endeavor (a good indicator of viability) I've seen is the Whisper-Gen, 800 watts per hour @ $15K+ with a something like a 20,000 hour operational life.

I spent of serious time running the numbers on this and I can't find a way to get them to work, maybe you’ll do better. If I was going to spend more time on this ides, I would play with the concept of Fluidyne Engines.
http://www.iedu.com/DeSoto/Projects/Stirling/Elsewhere/

Basically a piston-less Stirling engine water pump, where the water is the pistons and pumped water can be used to create electricity. But real cheap to experiment with!

I wish there was an easy answer, but then again so does the whole world.

Good luck.

Curbie