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how does this work? Answered

Recently I stumbled across this video
so, has anyone built one of these things? I am thinking about building one of these. any help would be greatly apreciated

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frollard (author)2009-03-22

The pot scourer has everything to do with it, inducing a 'thermal lag'. This is a closed system, there is no 'valve' anywhere. 1. Add heat, gasses expand, pushing piston out. Gasses in and around the 'heatsink' (pot scourer) flow outward, mixing with the hot air, cooling it quickly causing contraction. Momentum carries the flywheel around, helping press the piston back in; mixed with the contraction of the gasses pulls it in. The heatsink maintains relative 'coolness' from high contact area with a large surface area behind the flame. Heat applied quickly warms the area and pressure rises again; Repeat Again, there is no valve, no transfer of gasses in or out.

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aeray (author)2008-12-15

Yes, but how does it work?

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girrrrrrr2 (author)aeray2009-02-19

basically the candle makes the air in the tube expand. which in turn pushes that black thing out, as soon as it gets a little past the end its air pressure drops and pulls the black thingie back in... and so on... the black thingie has a wire on it so it can turn the wheel... basically it is all thermodynamics...

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aeray (author)girrrrrrr22009-02-19

But why does the pressure drop? Does the air cool off and contract? How so? Heat is still being applied. Why doesn't the pressure just keep increasing? Doesn't the entropy of a system always increase (2nd Law of thermodynamics)? Oh, and the "black thingie" is called a piston.

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girrrrrrr2 (author)aeray2009-03-21

the pressure drops because the piston lets it out at the end of a single cycle, during the start of the new one cooler air rushes in to fill the void of gas that is created when the air is let out and the wheel will help push the piston back in, which is then heated up and pushes the piston out and so on... the pressure would keep increasing if the piston was fixed in place and didnt let any gas excape, but it moves so it will increase until the piston lets it excape.

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mynameisjonas (author)aeray2008-12-15
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bikerbob2005 (author)2009-02-14

Yes sterling engines work .
Almost no toque , but can get increduble rpms from them
how they work? most use 2 opposed pistons balanced ,inject steam into one cylender forces the piston down .byodes law when steam expands it loses heat and pressure.a valve opens transferring the spent steam to below the piston.valve on other piston opens forcing it down .the first spent steam from the crankcase is forced back to boiler.then 2nd piston valve opens refilling the crankcase. insted of water to boil use freon and the warmth of your hand will run the motor.
for sale
wiki

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freakmonkey (author)bikerbob20052009-02-21

That's not at all how a Stirling engine works. lol

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bikerbob2005 (author)freakmonkey2009-02-22

I included 2 links in my post one to wiki that can be taken for whatever you want. the other is for a sterling engine that you can buy and does work. Most sterling engines use multi cylenders and can be best compared to a supercharged 2 stroke engine. unlike an old locomotive engine with one piston per wheel. temp /pressure differentials do not make a sterling engine work? pray tell what does then .Are you a troll ?contribute do not just bash. I studied the sterling cycle in school 35 years ago maybe cold fusion has replaced thermodynamics?PM mag had one in it in 1953 can not rember the month but had the Detroit news in same issue go do some research and get back to us on it please provide links on how it works where you come from {to the rest of the forum this is as nice as I get }

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freakmonkey (author)bikerbob20052009-02-23

Your very much right that Stirling engines do work by temp/ pressure differentials, however there are no steam injectors, dynamic valves, or boilers. Most Stirling engines are closed gas systems, however any working fluid will do the job. You would realize this if you actually read the Wiki you posted a link to.
http://en.wikipedia.org/wiki/Stirling_engine#Functional_description

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bikerbob2005 (author)freakmonkey2009-02-23

steam is a relative term for what we are dealing with.even to most simplest sterling engine has a form of a "valve" in it ,and what pray tell is that above the fire source? wow its a boiler .Wiki was not written by god it was and is by man sometimes parts are wrong . I would not build a thermonuclear device from the wiki, it is a point to start from.Then do more research.
however any working fluid will do the job
if I used hydrogen would it run backwards?how about mercury?
how about this please build us a working sterling engine and post your first instructable .making sure not to use steam injectors, dynamic valves, or boilers?

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freakmonkey (author)bikerbob20052009-02-24

Steam isn't a relative term, it refers only to vaporized water by definition. The simplest Stirling engines only have valves in the broadest definition of the word, and they don't open and close, meaning they're not dynamic. As for the "boiler" that is a heat repository, which again in the broadest definition of the word, is technically a boiler. I don't really get what your trying to say with your sarcasm about hydrogen and mercury, sorry. However; hydrogen is one of the most common working fluids in a Stirling engine. I have assisted in the construction of half a dozen different forms of Stirling engines, this is one of the simpler ones. I would not build a thermonuclear device from the wiki either, but it's not a bad place to start for the concepts.

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bikerbob2005 (author)freakmonkey2009-02-24

I am sorry by (me using the term steam ) most people slept through the classes on these kinds of science .so the term "steam" is relative for a superheated vapor.as it the term boiler . a valve is a valve if made to g-7 specks or a leather flapper.
I don't really get what your trying to say with your sarcasm about hydrogen and mercury
liquid hydrogen has some unique properties and the mass of mercury would make it a little tough for a low toque motor .
I have only seen one sterling engine that was truly in service (not desk toy) it powering a vacuum pump. would you mind telling me where you installed those 6 engines I would love to see them.

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freakmonkey (author)bikerbob20052009-02-25

I once saw a working Sterling engine used as a water pump. This wasn't one I helped with, it was an antique. Most of the Sterlings i helped with were used for power generation. They're very common on higher end yachts because they are so much quieter than internal combustion engines.

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westfw (author)2008-12-10

Do a web search on the video title (lamina flow stirling engine) and you'll get some more details. This looks pretty good...

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guyfrom7up (author)westfw2008-12-10

hmmm... looks very similar to another post made by a handsome, awesome guy. lol

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mynameisjonas (author)guyfrom7up2008-12-10

where? I don' see any handsome, awesome guys? lol jk but thanks for the link,

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guyfrom7up (author)2008-12-10

read this:
http://www.stirlingengines.org.uk/thermo/lamina.html

I'm not sure if they really work though... but the video is pretty convincing

this wouldn't be for the craftsman challenge, would it ;)

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mynameisjonas (author)guyfrom7up2008-12-10

I to (too?) am curious to see if it actually works and about the craftsman challenge, hmm... I haven't thought about that. I got dibs!!!!!

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