stovetop engine, and maybe more.

Discussion on Stirling or "hot air" engines (all types)
Post Reply
benoit
Posts: 3
Joined: Thu Dec 29, 2016 4:57 pm

stovetop engine, and maybe more.

Post by benoit »

good day everyone
i am new here, hoping to find a bit of information about stirling engines.

my project:
i spend a lot of time in the bush, off grid camping.
i built a small toy hauler out of a stock enclosed trailer. included a wood stove, insulation, solar panels, beds, led lights, external shower, cpu fans used as ceiling fans. it works great except there is always a potential upgrade to do.

this year i would like to include a stirling engine on that wood stove to help moving a bit more air than my eco-fan. if i could also include a small generator to that engine, it would be the very best of the best. all i need to produce is 2 amps at 12 volts(24 watts) and it could allow me to use all lights and fans in the trailer, and recharge my batteries at the SAME time. note: the whole thing draw about 1.5 amps. mainly, i want to move a lot of air. at -25 degres like i had last week, its rough and transforming that hot stove into a hot stove with a good fan is what i need.

my 2nd upgrade i have in mind is a powered fire pit, built out of a propane tank(been venting for 6 months now, i think its ready to try setting it on fire)
the idea being:
cooking on gas is great except when i run out of gas. i however never run out of wood. the main idea was to use peltiers and make a turbo powered eco-fan, push all that air in that stove and get it to heat as much as possible(look at the bio-lite, imagine it 10 times bigger and hotter). all i want to use it to is boil large amounts of water and fry bacon in the morning. a stirling engine might be potentially capable of providing that energy that i need there, except i would require a way to trottle it up and down.


anyways.
i guess that explains why i am here, and what i will be doing for the next few weeks.

luckily i have a lathe and a mill at home, the machining part shouldnt be the hardest part. its the types of motors and the desing i need to figure out.
lots of fun comming soon.

see you guys
Ian S C
Posts: 2218
Joined: Thu Dec 02, 2010 5:15 am
Location: New Zealand

Re: stovetop engine, and maybe more.

Post by Ian S C »

Here's my stove top fan.
Ian S C
[img]
Test 053 (800x600).jpg
Test 053 (800x600).jpg (186.32 KiB) Viewed 9797 times
[/img]
[img]
Test 053 (800x600).jpg
Test 053 (800x600).jpg (186.32 KiB) Viewed 9797 times
[/img]
benoit
Posts: 3
Joined: Thu Dec 29, 2016 4:57 pm

Re: stovetop engine, and maybe more.

Post by benoit »

that's a cool one for sure. beta?
Ian S C
Posts: 2218
Joined: Thu Dec 02, 2010 5:15 am
Location: New Zealand

Re: stovetop engine, and maybe more.

Post by Ian S C »

No it's a GAMMA.
Ian S C
[img]
Test 041 (640x480).jpg
Test 041 (640x480).jpg (132.21 KiB) Viewed 9767 times
[/img]
benoit
Posts: 3
Joined: Thu Dec 29, 2016 4:57 pm

Re: stovetop engine, and maybe more.

Post by benoit »

quite interesting.
i guess there are a million ways to build it.
any reasons why you went with the gamma instead of a beta?
Ian S C
Posts: 2218
Joined: Thu Dec 02, 2010 5:15 am
Location: New Zealand

Re: stovetop engine, and maybe more.

Post by Ian S C »

Yes the reason is simplicity, you don't have the displacer rod running through the piston, the displacer cylinder over laps the power cylinder. I built this one and another one that is a Ringbom motor, similar lay out, but it is too noisy, and it is actually too powerful.
Ian S C
Test 044 (640x480).jpg
Test 044 (640x480).jpg (125.21 KiB) Viewed 9746 times
Trevor
Posts: 228
Joined: Sun Nov 06, 2016 4:07 am

Re: stovetop engine, and maybe more.

Post by Trevor »

Hi Ian - Looks as if you used a conrod from another engine there. Very nice job of the plumber type blocks you have built. Looks as if the engine has a lot of power.
Trev
cbstirling2
Posts: 156
Joined: Sat Dec 17, 2016 9:35 pm

Re: stovetop engine, and maybe more.

Post by cbstirling2 »

Ian S C wrote: I built this one and another one that is a Ringbom motor, similar lay out, but it is too noisy, and it is actually too powerful.
Ian S C
So the ringbom is more powerful than the gamma? Is generally true?
Also why is it "too powerful"?
Do you have pictures of the Ringbom motor?
CBStirling2
Ian S C
Posts: 2218
Joined: Thu Dec 02, 2010 5:15 am
Location: New Zealand

Re: stovetop engine, and maybe more.

Post by Ian S C »

Sorry no pics at the moment of the Ringbom. I need to fit it with a larger fan to absorb some more of the power. When it gets up speed the whole motor starts to rotate on the stove because of the gyroscopic force of the fan. But the main problem with the Ringbom is the free displacer as it bangs up and down. Sometimes if you get it right it is quite quiet.
Bearings used on both motors are skate board size 8 mm shaft.
Ian S C
cbstirling2
Posts: 156
Joined: Sat Dec 17, 2016 9:35 pm

Re: stovetop engine, and maybe more.

Post by cbstirling2 »

Screenshot_2017-01-09-08-30-13-1.png
Screenshot_2017-01-09-08-30-13-1.png (279.07 KiB) Viewed 9718 times
Been reading about them, Square wave movement matches more the actual cycle. The screenshot is from Lloyd's thesis paper. LOW TEMPERATURE DIFFERENTIAL STIRLING ENGINE FOR POWER GENERATION
CBStirling2
Ian S C
Posts: 2218
Joined: Thu Dec 02, 2010 5:15 am
Location: New Zealand

Re: stovetop engine, and maybe more.

Post by Ian S C »

trev, all the parts for this motor were built for it, the only commercial bolts/screws are the 1/8" BSW bolts on the cap of the big end bearing of the displacer, and the 1/8" BSW bolts that hold the fan blades in place.
Ian S C
Trevor
Posts: 228
Joined: Sun Nov 06, 2016 4:07 am

Re: stovetop engine, and maybe more.

Post by Trevor »

It is a very impressive looking heat engine, especially with that large fan. It should would work with a generator as it looks powerful.
Your last post said that the Ringborn engine was more powerful. Do you know if they could be adapted to suit a axial flux generator. I am building one now for my next engine. I have written out the plans for it on paper and hope I can get it to work well.
Trev
Ian S C
Posts: 2218
Joined: Thu Dec 02, 2010 5:15 am
Location: New Zealand

Re: stovetop engine, and maybe more.

Post by Ian S C »

I do have a free piston engine with a linea/axial alternator, maybe this is something along the lines of what you are thinking. My first attempt was a BETA pattern, but I didn't get it quite right, I found later that a combination of large magnets, and lots of steel close by just don't work.
Ian S C
[img]
DSC00716.JPG
DSC00716.JPG (147.14 KiB) Viewed 9672 times
[/img]
Trevor
Posts: 228
Joined: Sun Nov 06, 2016 4:07 am

Re: stovetop engine, and maybe more.

Post by Trevor »

Single coil Ian? Could you have added a few more coils around the magnet to offset the flux around elsewhere, as the engine looks OK.
Trev
Post Reply