Paul,

What do you know about these?

What is Rotron Pressurised Cooling (RPC) system?

http://www.rotronuav.com/engines/rt-350rpc


This "patent" seems to be a variant or builds on the work of the
Norton-Garside cooler bur makes it a closed loop if you will.

http://www.enterprise-europe-network.ec.europa.eu/src/matching/templates/completerec.cfm?BBS_ID=176296&org=0&back=true&is_external=0&valid=0

( Details below the break-line)

These are on top of the other efforts  ( Diamond ? ) etc are engaged in...

My best,
Anthony


The cooling fan requires HP reducing the net HP out.
Therefor the BSFC is around .52 rather than .47 in the oil cooled rotor
Mazda.
Notice they don't mention the HP required by the cooling fan in the
propaganda :)
  From my book How to Cool Your Wankel


"However, for low-density fluids, such as gases, it is very easy to
expend as much mechanical energy in overcoming friction power as is
transferred as heat."
[What is being said here is HP is consumed by cooling drag. Since
cooling drag can be as high as 30% of over all drag the HP could be as
much as 30% of 200 HP or 60 HP. As you can see cooling drag becomes a
very important issue.] "And it should be remembered that in most thermal
power systems mechanical energy is worth 4 to 10 times as much as its
equivalent in heat."
[Here they are referring to the heat balance of most internal combustion
engines that only derive about 25% to 10% of the heat energy in a gallon
of fuel as mechanical HP.]

Paul Lamar


Paul,
The fan power loss is offset somewhat by the elimination of the corner,
side and oil seals' friction.
Interesting,
Barry

The friction is very low in a rotary to begin with.

The Austro/Midwest/Diamond engines use air cooled rotors.

Paul Lamar


Hi Paul,

I hope all is well - and keep fingers crossed on your TC system.

Here is the patent on SPRACS (mis-spelled as "SPARCS" in the link you
forwarded). It's actually a David Garside patent, and the trick is that
it is air cooling with added oil mist in a closed loop rather than
charge cooling, so it is an evolution of the "lost air" UAV Engines /
Austro system. The self-pressurized cooling air has a higher density and
hence higher cooling capacity than ambient pressure. Also the fan just
needs to keep the air circulating without producing pressure, and it's
not necessary to filter oil from the air outlet as you would on the UAV
/ Austro system.

The cooling air's pressure reduces the pressure difference between the
inside of the rotor and the combustion chamber and therefore
theoretically reduces the side and corner seal leakage, but the system
still needs seals.

Whether the system is as good as it should I don't know, but we have
actually issued a little optimization patent on this, in the best case
simply making a little slot in the compression area of a side plate to
automatically regulate the pressure rather than relying on leakage and a
pop-off valve.

David Garside also has a patent on a "Wankel" 2:1 expander as a
compounding device by the way. The turbo is the better way to go IMHO
though, because it can handle the heat more easily.



Best Regards,

Poul


Poul Henrik Woelfle

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