Look what I made.

[charby]

My FIL build one a few years ago from scrap auto parts. The displacing piston was built out of a shock tube.

[230RN]

^ Did it work, and at what altitude?

[zahc]

I have never seen a practical stirling engine...only knickknacks, demonstrations, and curiosities. I would love to find one that could put out a few watts and do useful work.

[Viking]

I have never seen a practical stirling engine...only knickknacks, demonstrations, and curiosities. I would love to find one that could put out a few watts and do useful work.

Submarine practical enough for you? Gotland class submarine.

While submerged, the Kockums-built Stirling engine Air Independent Propulsion (AIP) system is used to drive a 75 kilowatts (101 shp) generator for either propulsion or charging the batteries.

[230RN]

I have never seen a practical stirling engine...only knickknacks, demonstrations, and curiosities. I would love to find one that could put out a few watts and do useful work.

Even the early ones did practical work, like pumping water and so forth.  Previous linked citations of mine and others will point out that they are and were in practical use... if you'd care to review the thread a little more thoroughly.

https://www.youtube.com/watch?v=8mlyXRBLkqc

They didn't manufacture that one as a tabletop model, and 1/10th of a horsepower is 75 Watts.

"I have never seen" gamma rays, either.  Hence they do not exist.

Come to think of it, I have never seen you, either.  

Terry, 230RN

[charby]

^ Did it work, and at what altitude?

Yes if you got big enough fire underneath it. ~600 ft above sea level. He used a propane plumbers torch to get it warmed up and a big alcohol lamp (like used in a bio lab) to power it after it started.

He made it from plans he ordered from the back of some small gas engine magazine. I imagine if you do some google fu you can find the plans.

Flywheel was made from wood.

[zahc]

My definition of "practical" is the issue here. Submarines, old water pumpers, and engines made from plans in magazines are still in my "not practical" category. I want to get out my credit card and purchase a commercially-available stirling engine. All I see is the stirling equivalent of old hit-and-miss gasoline engines, at best.

[charby]

All I see is the stirling equivalent of old hit-and-miss gasoline engines, at best.

What do you mean? Hit and miss engines were the workhorse of rural areas before electricity arrived on the farm.

[birdman]

My definition of "practical" is the issue here. Submarines, old water pumpers, and engines made from plans in magazines are still in my "not practical" category. I want to get out my credit card and purchase a commercially-available stirling engine. All I see is the stirling equivalent of old hit-and-miss gasoline engines, at best.

http://www.whispergen-europe.com/index.php

[freakazoid]

My definition of "practical" is the issue here. Submarines, old water pumpers, and engines made from plans in magazines are still in my "not practical" category. I want to get out my credit card and purchase a commercially-available stirling engine. All I see is the stirling equivalent of old hit-and-miss gasoline engines, at best.

What are you looking for it to do?

[230RN]

Post deleted by poster

[Firethorn]

Friends of mine have a Stirling engine on their wood stove...

Now this I'm interested in.

Of course, I've been wondering if I could rig up a multiple horsepower stirling that's fired by oil heat and having the 'cold' side heat my house...

[zahc]

What are you looking for it to do?

Turn a generator/alternator.

[birdman]

Now this I'm interested in.

Of course, I've been wondering if I could rig up a multiple horsepower stirling that's fired by oil heat and having the 'cold' side heat my house...

They already have that for gas, see the link I posted.  The issue with getting substantial power density is getting the internal pressure up high enough, and with the temperatures involved, that means inert gas working fluid

[RoadKingLarry]

What do you mean? Hit and miss engines were the workhorse of rural areas before electricity arrived on the farm.

Wasn't so very long ago a fellow could still find an old hit and miss engine running a stripper pump on an old oil lease out in the sticks. Last one I saw still in use was only 8-9 years ago.

[charby]

I think a stirling engine would have a use if you had waste heat, such as if you heat with a wood stove. I think it would be cheaper and more efficient to have an electric engine or petro engine if had to create your own heat. Now something using solar radiation might have some merit.

[230RN]

Heh.  Look what I found.... V4 flame sucker.

https://www.youtube.com/watch?v=21xyKBRO_A8

I wish I still had my machine shop.  That video makes my hands hungry to do mechanical stuff again.  <sigh>

Then I found this before-and-after reconstruction of a hit and miss engine.  Note the knife switch for ignition.  Trouble is, it won't start without a dog barking.
:D

https://www.youtube.com/watch?v=Z5X0bIh2Up8

Terry, 230RN

[freakazoid]

Heh.  Look what I found.... V4 flame sucker.

https://www.youtube.com/watch?v=21xyKBRO_A8

I wish I still had my machine shop.  That video makes my hands hungry to do mechanical stuff again.  <sigh>

Then I found this before-and-after reconstruction of a hit and miss engine.  Note the knife switch for ignition.  Trouble is, it won't start without a dog barking.
:D

https://www.youtube.com/watch?v=Z5X0bIh2Up8

Terry, 230RN

That hit and miss engine is cool.

[Gewehr98]

I have a couple Maytag engines, and will probably have a Fuller-Johnson stationary engine running in the not too distant future.

The flame lickers are cute little engines, but don't produce much usable horsepower or torque.

Stirlings are better in that respect, but still don't produce like a proper internal combustion engine of equivalent weight and size.

[230RN]

"Stirlings are better in that respect, but still don't produce like a proper internal combustion engine of equivalent weight and size."

True in respect to the flame suckers, but don't lose sight of the fact that engineering advances for IC (Internal Combustion) piston engines really took off --to the point where multiple valvings, overhead cams, etc., brought them to a pretty darned high level of performance and efficiency.  

But on the other hand, although they've been around for a while, Stirling engines have only "recently" been subject to serious high-level engineering development.  Notably by Phillips.

(They wanted to sell more of their radios in undeveloped areas, and needed "fuel-less" engines (Stirlings) to power generators to run their radios.)

For one thing, Stirlings can run on any heat source from sunlight to radioactive decay without the refining and distribution problems of the fuels used in IC engines --from pure hydrogen to heavy diesel fuels.

For another, their efficiency and utility largely depends on two other factors, the regeneration chambers and the density (pressure) of the working medium.  I can't seem to emphasize that latter fact enough.

These enhancements are largely missing from your usual table-top "models" or fireplace blowers, and those seem to be the source of most folks' impressions of Stirling engines as inefficient and unreliable.

Please understand that I am not "selling" the concept of Stirling engines as better than IC or turbines.

But as an example as to how "serious" engine development can change one's perspectives, consider the example of jet engines and gas turbines, which have only "seriously" been developed since, say, the mid-1930s.  But the IC piston engines had already been around for nearly five or so decades.  So the upshot of further development since then is that nowadays, most commercial jets and helicopters are powered by jets and turbine engines rather than piston engines.

And speaking of "weight," look at the weight-saving techniques that have gone on with IC engines... like aluminum and magnesium  components... these enhancements are not seen in the tabletop models and fireplace fans which have flavored some folks' impressions of Stirling engines.

Terry, 230RN

[birdman]

Also, 230RN, stirlings, unlike gas turbines or internal combustion engines, do not require the utilized heat to pass -through- a solid medium.  That is why peak (IC) or sustained (turbine) combustion temperatures can exceed the melting point of their materials (which is saying a lot w.r.t. Gas turbines, given the alloys used).  In a stirling, not only does the hot side heat have to pass through a solid, but that solid must also withstand the stresses of the internal high pressures, which unlike IC are sustained. 
So while for a given temperature difference, a stirling can be closer to theoretical, the achievable temperature differences compared to other systems render their allowable efficiencies lower. 
That is why they are typically used for lower temperature heat engines--if the hot side temp can be withstood, the stirling will have better efficiency. 
HOWEVER, by definition, a stirling is a reciprocating system, it can't be continuous like a turbine, and that requires further engineering for lifetime considerations.  Many of which have been solved (e.g. Stirling cryocoolers/flexure bearing systems).

[Gewehr98]

I've seen one or two ancient Rider and Ericsson Stirling engines at the yearly Badger Steam and Gas show. 

They're usually running a low-amperage generator or pumping water. 

Besides the Philips 200W Stirling gensets and those used by NASA, I would imagine that development of the Stirling Cycle Engine needs an infusion of cash to go further these days...

[230RN]

Also, 230RN, stirlings, unlike gas turbines or internal combustion engines, do not require the utilized heat to pass -through- a solid medium.

I think you meant,

"Also, 230RN, stirlings, unlike gas turbines or internal combustion engines, do not require the utilized heat to pass -through- a solid medium."

Gewher 98 said,

"Besides the Philips 200W Stirling gensets and those used by NASA, I would imagine that development of the Stirling Cycle Engine needs an infusion of cash to go further these days."

True.  One problem is that turbines and IC engines are so far ahead in their development that it's economically unfeasible to develop Stirlings much further except for special purposes.

Terry

[birdman]

I think you meant,

"Also, 230RN, stirlings, unlike gas turbines or internal combustion engines, do not require the utilized heat to pass -through- a solid medium."

Gewher 98 said,

"Besides the Philips 200W Stirling gensets and those used by NASA, I would imagine that development of the Stirling Cycle Engine needs an infusion of cash to go further these days."

True.  One problem is that turbines and IC engines are so far ahead in their development that it's economically unfeasible to develop Stirlings much further except for special purposes.

Terry

Correct.
Though the link I posted is for HOME 1-couple kW level stirling generators/heaters

[230RN]

^ That link didn't work for me, even when I truncated it to:

http://www.whispergen-europe.com

Here's a longish but very informative video on the Phillips generator set, which runs on paraffin (kerosene).  The remark about transistors relates to the fact that about that time transistorized radios got popular, and you no longer needed high power to run the vacuum tube radios of the time.  I'm not sure I'd want to run it in an enclosed space, as he remarked, though.

Note the high pressures involved.

https://www.youtube.com/watch?v=M9UKu-AP02k

Terry, 230RN