Posted by Jim Wilkins on April 19, 2009, 8:37 am
> ...
> When I read Jim's idea I immediately thought "Water Clock".
> Curbie
http://www.history.rochester.edu/steam/hero/
Posted by Morris Dovey on April 19, 2009, 4:42 pm
Curbie wrote:
> If it's not proprietary:
> 1) What's the turn ball valve for, changing air flow for varying
> temperatures?
It allows adjusting how much expansion takes place before the
contraction takes place.
> 2) Shouldn't the regenerator be insulated to "beat the band"?
That helps.
> 3) Are you using copper scouring pads Chore Boy or the like in
> the regenerator?
I'm using bundles of thin brass tubes.
> 4) Is the reason for your proposed regenerator design to transfer
> greater heat without impeding air flow?
Yes - we're trying to extract heat from the hot air as it moves from hot
head to cold head during expansion, and return that heat to the air as
it moves back from the cold head to the hot head. It's a heat re-cycling
mechanism.
> 5) Since the engine is for a water pump and since Striling cycles
> depend on temperature differences, shouldn't the cold-side be water
> cooled (route pump water through it on its way to where ever it's
> going)?
Simon Popy assembled his second engine with a PVC pipe jacket on the
cold head so he could give the idea a try. I don't think he's actually
circulated water through it yet.
> If any or all of the questions are proprietary don't bother to answer
> them.
What you see on the web page is pretty basic physics. The stuff that
isn't so basic (and that, while too expensive for a DIY irrigation pump
might have other application) may or may not find its way to a web page.
As you might expect, ideas come a lot faster than their implementation.
>> It seems like it /should/ be possible - I just don't (yet) have a good
>> handle on the "how".
> When I read Jim's idea I immediately thought "Water Clock".
I've added that to my list of things to learn about.
--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/
Posted by Jim Wilkins on April 19, 2009, 5:26 pm
> > When I read Jim's idea I immediately thought "Water Clock".
> I've added that to my list of things to learn about.
> --
> Morris Dovey
Did you look at this calculus-free fluidyne analysis?
>http://www.ornl.gov/sci/engineering_science_technology/eere_research_repor=
ts/thermally_activated_technologies/engine_driven/stirling_rankine/modeling=
_and_simulation/ornl_conf_830812_49/ornl_conf_830812_49.pdf
Posted by Curbie on April 20, 2009, 12:39 pm
>Did you look at this calculus-free fluidyne analysis?
>>http://www.ornl.gov/sci/engineering_science_technology/eere_research_reports/thermally_activated_technologies/engine_driven/stirling_rankine/modeling_and_simulation/ornl_conf_830812_49/ornl_conf_830812_49.pdf
After reading it last night, smells like the foundation of a computer
model to me.
Thanks.
Curbie
Posted by Curbie on April 19, 2009, 7:45 pm
> 2) Shouldn't the regenerator be insulated to "beat the band"?
>That helps.
Generally speaking since Stirlings operate of the heat difference
between hot & cold I think anything that expels from the from the cold
side and keeps heat in the hot side, with the only path for heat to
escape is through the regenerator on to the cold side will make an
efficiency improvement.
>> 3) Are you using copper scouring pads Chore Boy or the like in
>> the regenerator?
>I'm using bundles of thin brass tubes.
Have you played with scouring pads, Chore Boy make in copper if I
remember?
Total area & type (copper, aluminum, ...) of regenerator material
seems to determine volume of heat stored, while the thickness of
regenerator material seems to determine the rate of the material's
heat transfer. Both are important.
>Simon Popy assembled his second engine with a PVC pipe jacket on the
>cold head so he could give the idea a try. I don't think he's actually
>circulated water through it yet.
Well, you can beat yourself to death over fractions of a percent of
engine efficiency, but sooner or later you're going to have to put the
torch down and get the best design you have to run on solar heat.
Best wishes.
Curbie
> When I read Jim's idea I immediately thought "Water Clock".
> Curbie