Hey Guys,

Another piece of the puzzle we must talk about is the heat transfer
through the rotor housing. We need to understand what we want this to
be. Lets take a look at some extremes

If we have a super low heat transfer value I assume we get higher rotor
surface temps and less heat transfer to oil which may negate the need
for rotor cooling. That's a benefit for sure and materials with such a
low transfer value tend to survive high heat well. What are the downside
to really hot rotor surfaces?

Assuming we get a super high heat transfer value I assume we get lower
rotor surface temps but might require increased oil cooling
requirements. Not such a benefit and also materials with high heat
transfer values tend to be rather weak.

I am just starting a conversation here on this topic and I might be
wrong on some of my assumptions. FEA modeling would be best for this but
a combustion chamber model would be needed as well. Also lets extend
this topic into the housing surfaces as well.

Rob Woods

Lubrication breaks down for apex seals.

Paul Lamar

Rob,

A hotter rotor doesn't help as much as a hotter combustion chamber area.
 The best theoritical place to keep hot is to  isolate and insulate the
combustion sectional arc of the outer housing.  That could only be done
with very precise water flow controls.  The second best place is to
improve the heat retaining charteristics of the rotor bathtub. For that
we need a strong insulating material that also has the strength to hold
the apex seals in place.  Titanium alloys are contenders.   If a steel
plate could be cast into the rotor depression that would give us the
best of both worlds.   A very hot plate that is insulated and kept hot.
The research would be in determining the temperature regulation of the
plate.  We don't want it to remain so hot that when fuel mists contacts
it on the intake stroke we have ignition.

Another idea that needs to followed up on is to contact the company that
licenced the BAM coating technology from NASA and see if we can get some
info on heat tolerance and modulus of elasticity. That technology could
be a major breakthrough for the rotary engine.  Apex seals with the
strength of iron but a sliding co efficienct half that of Teflon.  And
if it works on Apex seals why not side housings?

Doug in Japan.