Who here knows anything about Stirling engines?

[RogueFactor]

Educate me, please.

[Geronimo7]

Never even heard of it, and thats bothers me a little. It's gotta be out of an airplane or something huh

[BigEvil]

http://en.wikipedia.org/wiki/Stirling_engine

[RogueFactor]

http://en.wikipedia.org/wiki/Stirling_engine

Thanks, Ive already read that. I want to speak to someone with more in-depth knowledge.

[Papa_Smurf]

I'm big into LPD engines such as this and hit and miss engines.What do you need to know?

[tymcneer]

Please keep this public! I have an interest in hit and miss engines, Stirlings, steam, etc... I'd like to hear more about it from someone that knows something!

Ty

[RogueFactor]

I'm big into LPD engines such as this and hit and miss engines.What do you need to know?

Well, Id like to know the stuff about Stirling engines that arent in the books or wiki. Like, what is the temperature differential for them to have a decent energy output? I know there are the desktop versions, which are nice novelties, but they have little application use.

Also, I dont know the acronym LPD, or the term 'hit and miss' engines.... On these subjects, I am at best a novice.

Please educate me with what you know.

[Papa_Smurf]

Well, Id like to know the stuff about Stirling engines that arent in the books or wiki. Like, what is the temperature differential for them to have a decent energy output? I know there are the desktop versions, which are nice novelties, but they have little application use.

Also, I dont know the acronym LPD, or the term 'hit and miss' engines.... On these subjects, I am at best a novice.

Please educate me with what you know.

I have two on my desk, one will run on a ceral bowl of ice cubes, the other will run on a bic lighter.

On the other end of the spectrum, my father built one that is wood fired. It requires 300 degrees to just start, more when put under load. It is strong enough to be used to power a full size (circa 1800) saw mill at the local threshers reunion.

I'm so sorry, I meant LTD. That is low temperature difference.
Hit and miss is another kind of engine. The first "reliable" internal cumbustion engines.

[RogueFactor]

Thats a good start Papa!

How about the minimum temperature differential required for the engine to be a viable application?

Did you build the desktop novelty Sitrling engines yourself? Or are they the purchased kind?

Lay down for us some knowledge on the subject. The stuff youd have to learn in school(or the real world) to know.

[Papa_Smurf]

Thanks,
The minimum temp difference for it to be a viable application? Depends on what load it's carrying, if it's using flywheels to maintain momentum, and several other variables.

My fathers needs between 300 to 800 to do anything. It has two 400 pound flywheels.

What kind of load are you asking about? I can call up my father with any big questions, that would make his day.

I built them myself. One is a glass test tube and steel balls from a bearing.

The stuff you'd have to learn in school to know? Heck man, I can tell you alot. I'm only a high school student. I spend alot of time in a shop with this stuff, you don't need a class, you need someone that knows it all and can take you into the shop and have you tear one apart and put it together again. I spend the forth of july weekend at a thresher's reunion every year, the following week I spend at a steam power convention. They have all kinds of workshops at these things I always go to all of them.

But again, I will call my father and get any info you want.

[mostpeople]

Thats a good start Papa!

How about the minimum temperature differential required for the engine to be a viable application?

Did you build the desktop novelty Sitrling engines yourself? Or are they the purchased kind?

Lay down for us some knowledge on the subject. The stuff youd have to learn in school(or the real world) to know.

what does viable mean?

[mostpeople]

I always look to the equations for answers...

as an engineer you should find this useful...

http://www.bekkoame.ne.jp/~khirata/academic/schmidt/schmidt.htm

[RogueFactor]

Viable meaning something for practical use.The desktop versions are nice novelties, but have no practical use. If they could power a calculator, recharge batteries, or something then theyd have a practical use.

Like with almost anything, there is the textbook calculations and the theoretical--which are fine. And then there is real world. I prefer real world knowledge. When someone has that kind of knowledge, they can tell you all the things that dont work in the real world, but would appear to work on paper.

From what Ive read, the reason why Stirling engines arent vialbe as an energy producer is because they cost allot to make. From what I understand, the heat exchanger is the area on these engines with the most potential for advancement. Is that true? Would your dad be able to shed some light on this.

Also, I guess Dean Kamen(inventor of the Segway) is into Stirling engines, and has been developing their use with water purifiation systems for poor countries/peoples. He has patented a heat exchanger that has greater efficiency. He is also working with a European company to use Stirling engines in cars over there.

Then there is also this... http://www.stirlingenergy.com/whatisastirlingengine.htm . Solar combined with Stirling engines which yield greater energy output than solar alone. Very interesting stuff.

I read all this stuff, but cant tell what really has potential and what doesnt. What works in the real world and what doesnt. And thats what Id like more knowledge of, your knowledge and your fathers knowledge.

[Papa_Smurf]

Theroritically, you can make one big enough to power anything. The ball bearing one can power a bunch of LED lights, or a small fan.

You are right about the real world versus on paper deal.

Our heat exchanger does have a really long path, it is a waterfall type radiator. There is a fan inside of it powered by the engine.

I believe your big question(can it really be worth it to use one) is really a hard one. Yes, it can be worth it, but it isn't cost effective to do solely for that purpose. If you already have heat from something, then yeah, use that energy.

[txaggie08]

Hit and miss is another kind of engine. The first "reliable" internal cumbustion engines.


Are you talking about what we always called a "popping john"? Saw an absolutley MASSIVE one(I could have damn near crawled down the cylinder at my current size) running a bailer one time......took a small semi to move it, supposedly came out of some big grain processing facility.

[Papa_Smurf]

Are you talking about what we always called a "popping john"? Saw an absolutley MASSIVE one(I could have damn near crawled down the cylinder at my current size) running a bailer one time......took a small semi to move it, supposedly came out of some big grain processing facility.



Yeah, same thing. Just another name.

[Papa_Smurf]

Ok guys, I'm at my grandfather's house right now so myself, my father, and grandfather all talked about steam power and all this stuff for about 4 hours just now.

My grandfather said this is a good discription of the bearing type of sterling engine:

The starting position of the engine is tipped to the left. The alcohol burner heats the air in the right area of the test tube; the air expands and pushes the pneumatic cylinder and thus the test tube upwards. The marbles roll to the right. The hot air is then forced to the left, where it gets cooled. The cool air shrinks, the pneumatic cylinder moves downwards and the test tube tips counter clockwise. The marbles roll left and the air is pushed right, to the hot side. The air expands and moves the piston again. And so on and so forth.

There's a piece of steel wool in the bottom of the test tube (hot side). It's both, heat exchanger and cushion (to avoid the test tube to break). In the test tube are placed five marbles that act as displacer piston as they move the air from the hot side to the cold side and backwards. As friction is a common problem in building Stirling engines, I decided to use a low-friction "LEGO" pneumatic cylinder as working piston. Furthermore the whole system has to be 100 % leak-proof; I used an original Edradour Scotch Whisky cork to close the test tube and finally silicon to seal all crucial parts. To make the engine finally run some fine tuning in terms of balancing the test tube and positioning the pneumatic cylinder and the heat source is necessary


He also said that his engine like this turns two 12 ounce brass flywheels at 700 rpm. They are 5 in. in diameter. It can power a crank type pencil sharpener.




He also told me the engine at the convension I saw this summer is one he built at age 17 in Gary IND. Said it needs 1100°

[Resurection]

fascinating... this is better than History/Discovery/Science channel sometimes. :clap: