Hot Air Engines

[xxParticipant @xx]

Though I would start a thread to post links for hot air engines.

 

This one for starters: http://www.moneryengines.co.uk

[xxParticipant @xx]

[Ian S CParticipant @iansc]

Hi Chris, At one stage in the thread in the begginers section there was a thought of starting a dedicated hot air / stirling engine thread, but it never happened.

Had a wee look at the site you put up, interesting, I imagine that the aluminium cylinder bore is anodised, Andy Ross used that for some of his motors. Bare aluminium regardless of what you use as a piston would not last too long metal to metal. I try to make my motors with the most ideal materials I can find, or afford (they are all built at minimum cost). Ian S C

 ps., Perhaps we need a sepparate subject heading.

Edited By Ian S C on 08/07/2011 15:43:32

[David Clark 13Participant @davidclark13]

Hi There

You can discuss hot air engines here.

regards David

Edited By David Clark 1 on 08/07/2011 17:02:51

[xxParticipant @xx]

Thanks for pointing that out David. Out of interest why is the Hot Air thread under beginners? Hope you’ll agree that there is a place for one in the main part of the forum as well. Regards Chris

[David Clark 13Participant @davidclark13]

Hi There

Got to forums, click start new thread.

You tell me where you would like it.

It had to go somewhere.

regards David

 

 

[xxParticipant @xx]

Just updated the site with more details of how these engines work. Hope to put soem plans up soon.

 

http://www.moneryengines.co.uk

 

Edited By Katy Purvis on 01/06/2015 12:21:20

[alan frostParticipant @alanfrost17805]

At one time I had an interest in hot air engines , after all I spent a great deal of my life working for Philips and I live more or less, in Stirling. What puzzles me about them is that hardly anyone builds one with a useful (lets say 1 HP plus ) output. There does n’t seem much point in building yet another engine to run off the heat of my hand and produce a picowatt.

I know its not easy but Philips developed several powerful engines in collaboration with Ford and GM ,and the Swedes still have I think submarines powered by them-and all the Philips info is published. Yet year after year I used to visit the Stirling stand at model exhibitions only to see yet more sizeable engines strugging to keep a 100W bulb glowing. Nothing wrong with toys but surely a , if not the , point of a Stirling engine is that as an external combustion engine it could burn any fuel, and could produce useful amounts of power.

Engines are supposed to be prime movers. With a few honorable exceptions hot air engine builders seem to produce mainly microdust movers.

The Philips work came to nothing , mainly because the advent of the transistor meant there was less need for power plant to drive radio and TV and the Stirling engine is pretty unsuited to car propulsion (although modern hybrid cars might have changed this picture ) .

Hoping someone will prove me wrong.

[adyParticipant @ady]

The efficiency seems to be very good if they are well made, I’ve been looking at solar stuff recently and have a suggestion in case anyone is interested.

 

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

 

There is a flat lens called a fresnel lens, the most obvious application is as a magnifyer for an A4 page if your eyesight is dodgy.

 

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

 

A decent sized one can actually melt metal, the efficiency of heat generation because it’s simply a focussed beam of light is 99% kind of thing.

 

FREE ENERGY SOLAR POWER STIRLING ENGINE FRESNEL LENS

http://www.youtube.com/watch?v=A_AFnW1bZL8

[adyParticipant @ady]

There are things like thermal efficiency and dollar cost per watt of energy output to take into account.

 

I found an interesting tome here, and as it said

 

“solar panel manufacturers make solar panels out of fossil fuels…because it costs too much to make them out of solar energy”

 

http://www.lowtechmagazine.com/2008/03/the-ugly-side-o.html

 

Maybe the solar powered stirling engine of the future will be capable of cracking this problem….

 

The biggest problems seem to be generating heat.

Converting that energy to a useable or storeable form

Then transmitting it to the end user

 

http://www.lowtechmagazine.com/2011/07/solar-powered-factories.html

 

Edited By ady on 14/10/2011 07:46:44

[adyParticipant @ady]

I’m always inspired by simplicity, John Logie baird inventing television when he was on his uppers by using a hatbox and some knitting needles which set him en-route, about 12 months later, to the first ever analogue transmission of still and moving images.

 

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

 

 

There are solar collectors known as flat plate collectors, basically a metal plate, painted black on the front to absorb light energy and the metal behind the coating is a heatsink to store the solar energy.

If it’s colour is black, then it absorbs around 100% of any solar energy.

 

http://en.wikipedia.org/wiki/Solar_thermal_collector#Flat_plate_collectors

 

So if I take a flat sheet of aluminium foil, paint it black on one side, then hang it behind a window in my house with the black bit facing outwards….have I just made myself a free solar powered home heater?

Or even a sheet of black rubber, which is what they use in the bottom of swimming pools to keep them warmer

Edited By ady on 14/10/2011 08:49:00

[Ian S CParticipant @iansc]

ady, you would be even better if the aluminium was black anodised rather than paint. Ian S C

[Sub MandrelParticipant @submandrel]

Striling and other similar engines are very handy in remmote parts as you can power generators with things like dried dung, grass or even rubbish in areas where firewood is scarce. Less maintenance and skill needed than with steam or I.C. as well.

 

Neil

[lyricParticipant @lyric]

There are a few mediocre Stirling Cycle Engines here.

 

http://youtu.be/OGba0q4kaXs

[Ian S CParticipant @iansc]

Thanks Lyric, I rather likw theTMG made by Barumman, my only problem was that I,m on dial up, so it took a while to get his vidio, If I can get the two containers for the displacer, and a bit of Beryllium Copper of suiyable thickness, the rest I’v got. Ian S C

[Ian S CParticipant @iansc]

Got the first of the two stainless containers I require, 90 mm dia inside, want one with 85 mm outside dia, when I go to town next week I’ll have to go round meassuring SS containers.

Ian S C

[Gordon WParticipant @gordonw]

Ian S C Do make sure you take someone with you, you will get a lot of interest when you start measuring thing in supermarkets, been there.

[Richard ParsonsParticipant @richardparsons61721]

Hi Alan, I have long wanted to build a Phillips rhombic drive engine with a rollsock to develop about 3 to 3.5 bhp. I had the drawings but no clue as to size. I do not think that I would care to try where I am now. I have enough trouble collecting 8mm fine bolts to rebuild an almost new oriental bicycle.
I have just had a thought. If I can find an old 4 stroke single engine ( or just the cylinder of it) may be if I can drop my hand on a very small intermediate stainless milk cooler – or perhaps a cooking pot. The great Mr Rizo (of Malta) did a lot of work using mesh displacers. Hmm stuffed with kitchen foil –I can get that from the supermarket-. Problem is the roll sock this retains the pressure in the power cylinder/hot/cold end. So I can use an open crank case or one which is just muck proof. The gears for the rhombic drive could be pricey. Waite someone made a type of the rhombic using a form of 4 bar linkage. This allowed him to use the Phillips concentric power piston and displacer drive.
Problem is most of the good stuff was bought up years ago by Orientals with suitcases of cash.

 

Any ideas?

Rdgs

Dick

[Jim GreetheadParticipant @jimgreethead]

Hi Dick, nice to see you still active (and complaining).

 

Your mention of the rolling seal reminded me of the Tailer Thermal Lag Engine in which Tailer used a small inner tube as the seal.

 

It might be a bit off-topic since the Thermal Lag engine is (arguably) not Stirling but the patent application is worth reading for the humour in it – yes, humour – unusual.

 

The patent is US patent 5,414,997 by Peter L Tailer for a Thermal Lag Machine. It is dated May 16 1995.

 

Cheers

Jim

 

[Ian S CParticipant @iansc]

I’v got a rhombic on my list of motors to build, I’v got a stack of gears in my collection, now I need one more so I have a pair!!

I.ll be looking in department stores, and theres one or two kitchen hardware stores, if I can find them. In Christchurch these days its hard to find places, you go to where they were the last time, and they’v moved, or the building has been knocked over. Parts of the central city are still cordoned off, with some large buildings that are going to take many months to demolish.

Dick I got a cylinder from a cheap Chinese air compressor (50 mm bore), it has a damaged cylinder base flange (if it had been my compressor, I think I could have rebuilt it), thats lined up for a future motor. Ian S C

 

[Richard ParsonsParticipant @richardparsons61721]

Hi Jim! A belated Happy New Year. I meant to E mail you but I went ‘arm over anchor’ just before Christmas. We had a small snow fall so I cleared it and gritted my steps. Problem was that my step daughter thought the grit looked nasty so she had the steps swept and scrubbed. It froze, I went ‘arm over anchor ‘in the dark down some 4 steps. I do not bounce as well as I used to. So I am still creaking around.

The Stirling engine I would like to build for a mate’s boat on Lake Balaton. I know that Stirling (external combustion) engines like to run at full speed; however with a variable pitch prop (Stuarts used to make them) it could be controlled (and reversed. I could get round all sorts of regulations which apply to the ‘Infernal Combustion’ engine used on the Lake. I must poke the ‘authorities’ with a sharpened stick on that one.

The problem I have is I do not know what size cylinder would give me the required output. My next door neighbour’s lad has just piled in a 2 cylinder ‘Qwakayamahonduki’ it looks a mess but I think the cylinders are still intact.
Can anyone give me a clue on that topic?

Ian Hi Happy New Year etc. It still seems to be a bit ‘shaky’ down your way, but I hope you are OK. There is another version of the rhombic drive. I have a book with it in but I have cannot find it at the moment. I think it does not use gears, but I am not certain.

[Ian S CParticipant @iansc]

Richard, Christchurch has had about 10,000 aftershocks in the last 15 months, quite a number in excess of 5 on the Richter scale, I live about 40 Km out of town, its usually only the ones over 5 that we feel here, a couple today.

There is a group in UK with stirling engine boats. The motor would need to be fairly large, or pressurised, and a reasonable sleak hull, ie., long and narrow. If I was nearer water I might be interested in something like that myself. I have read, and seen a photo of a stirling outboard motor. The power would be similar to an electric trolling motor, and dead silent. Ian S C

[Gordon WParticipant @gordonw]

Engine I am ,still, building has power cylinder from 2CV Citreon 74mm bore, with leather washer piston. They should be easy enough to get. No idea of power output but hope for something usable.

[Ian S CParticipant @iansc]

Not many 2CV Citreons in NZ, and those that are, are kept by collectors, and I imagine that they hang on to all the bits. Ian S C

[Jim GreetheadParticipant @jimgreethead]

Here are some Stirling powered boats Dick (you have probably seen them):

 

http://www.youtube.com/watch?v=1YrnzwHBTZ8&feature=related

 

One of those blokes might be a good contact.

 

Keep taking the medication

 

Jim

 

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