As  to injection, I've been thinking about some sort of Stratified-Charge
Quasi-Diesel.
I.E., starts with spark plugs, but runs as a straight Diesel once it
gets going.
 There seem to be several design efforts going this way, but
very quietly !

I think the key is to use a Turbo to boost overall compression ratio
into the normal Diesel range, and maintaining the heat generated by the
turbo's 2:1 to 4:1 pressure ratio. Hence no Intercooler and no Throttle.

I.E., recover some exhaust power, muffel the exhaust, eliminate intake
pumping loss, and perhaps even generate a little torque during the
intake cycle.

Assuming lower exhaust temperatures of a diesel, use of best apex seals
and modern coatings, how high can the inlet temperature go ?  The great
unknown !

"Thinking Outside the Box"
JCP

Hey, JCP:

I'd love to share some thoughts with you about stratified charge diesel
rotary.  The John Deere/NASA studies of the SCORE engine really got me
thinking "outside the box" on the 13B.

What do you think of this proposal?

Take a stock 13B and P-port
 the intake.  With 9:1 compression ratio,
direct inject diesel (JetA) same location as the hydrogen rotary.
Instead of ignition from a spark plug (of course a spark would never
ignite diesel at these low compression ratios) a hydrogen-fed injector
with spark incorporated would be located at the spark plug hole.  This
H-injector would send a puff of hydrogen into a small pre-chamber and
ignited by the spark, sending a small flame into the main combustion
chamber to ignite the diesel.  The hydrogen would be provided by any one
of the current "Hydrogen on demand" systems in use today.  Actually,
just about any fuel could be used in this model since the ignition
source is a flame, not a spark. (Omnivorous fuel?)

What would be the challenges of this type of SCORE development?  There
must be something missing otherwise John Deere/NASA would have developed
this by now, you would think?  I, for one, believe it has some
 merit but
I don't fully understand the chemestry/mechanical challenges behind it.

Greg Fleming
London, Ontario, Canada


Greg:

Diesel will spark ignite when atomized (think of the oil burner in a house).

Looking at patents and photos of what Wankel-Super-TEC and others are
doing,
it appears they are all going the same way.

As Turbo spins up overall compression ratio becomes that of a Diesel.
Think in terms of a two stage machine.
Two stages of compression, Turbo then Wankel.
Two stages of expansion, Wankel then Turbo.

If the heat between Turbo and Wankel is not dumped via an Intercooler,
air temperature will be more than enough to self ignite Diesel or JP4
injected near TDC.

Efficiencies could approach that of a Diesel, due to the high overall
compression ratio.

Unknowns if a converted 13B will survive 60 inches of manifold pressure.

1) High inlet air temperature vs rotor lubrication.
2) Diesel
knock fracturing apex seals.
3) Transition from a sputtering start on spark to compression ignition.
4) Cooldown/spooldown on landing to the call for full power for a go around.
5) Can a turbo be found that will satisfy a 2:1 pressure ratio at sea level
and 4:1 at 15,000 feet, without a waste gate ?

"Thinking Outside the Box"
JCP