Is there a Sterling Engine that is not a toy? - Page 5

 

says...

WhisperTech <http://www.whispertech.co.nz/>  makes a small Stirling
generator designed primarily for sail boats.  It runs as a combined
power/hot water source with microprocessor control to keep the sailor
warm, supplied with hot water and the batteries topped off using diesel
fuel.  Virtually silent (55 dB at 1 m.,) very elegant (lots of titanium
and stainless steel,) and as I recall about US$15,000.

Electrical output is 800W (about a horsepower.)
Heat output is 5500 W.
Consumes 0.75 l/hr diesel or kerosene at maximum output.

 



Bravo! You found an actual working sterling engine!!!!! my bad
http://www.whispertech.co.nz/main/stirlingcycle/

 



I think it is Stirling, not Sterling.
Powergen, a power company, in the UK, who have partnered up with Whisper
Tech in NZ to make the WhipserGen Stirling mCHP (cogen) unit, which is being
currently implemented in 550 new homes in Manchester.

 

The biggest problem with Stirling engines (from a power / size ratio
perspective) is that since the working fluid is sealed in, the heat must
be transferred into it thru the 'cylinder' walls.  It is this heat
transfer which is the limiting factor in such engine types.  Models look
OK because the surface area / volume ratio is relatively large on that
small geometric scale.  As soon as you start to scale it up, there isn't
enough surface area (relative to the greatly increased volume of working
fluid) to get the heat into the working fluid quickly.

This is why you typically can't find anything bigger than a model - save
for the ~1hp unit sold by WhisperTech - still a far cry from your
requested 15-20 hp.

Rory


me@here.com wrote:

 

EPM NNTP wrote:

If it's simply a technical problem then I'm sure there is a solution.
For instance, if the problem is that of surface to volume ratios on
the cylinders gets bad for big cylinders then why not use small ones?
That is, use a dozen small diameter cylinders in place of one large
diameter cylinder of the same volume.

Of course, I was never terribly clear how stirling engines are all
that much different from a steam engine with attached condenser,
except perhaps that stirlings don't require a phase change of their
working fluid.

Anthony