I think the Honda turbofan engine is for real, and may be the final
nail
in
the
coffin of the Eclipse. GM had the ideal small aircraft engine on
their
test
stand about 30 years ago - a sidewheeler regen gas turbine that had
on
point
specific of better than 0.5. but it and the GM Wankel fell under the
corporate ax as a victum of the CAFE rulings- Vance
Hi Vance,
what's a "sidewheeler regen gas turbine?
Please answer to: rijakits@cwpanama.net , if it doesn't fit in this
newsletter....
Thanks,
Thomas J.
If I was succesful, there should be a schematic from the Chrysler turbine
car progam of 40 years ago. Turbine exhaust has an excess amount of thermal
energy, at a high tem.p If you extract heat from this exhaust and introduce
it
after the compressor, and before the combuster, the amount of fuel burned
to raise charge temperature for the turbine is significantly reduced.
The side wheels store some of this heat in a mesh of stainless "soda
straws". The wheel is turning slowly and lines up with the compresser
outlet adding this heat to the flow going to the combuster. Sounds complex,
and it is, but this is the most compact system for moving this amount of
BTU's around. The straws are also part of the labyrinth sealing between
the low pressure exhaust and the high pressure combustion chamber.
Several makers employed this system - Ford for some marine applications
and GM for their proposed Camero class turbine car. Without regen
turbines of this size are about 1 lb/hp/hr or worse. with this GM
could get 0.5 on point. Part power is still the pits, and the car was
projected
to do about 11 mpg city 18 highway. But it was a "JET "and would have
sold. But the gas guzzler fines would have been really bad. Only auto
production rates could have made this affordable. but what a neat
200hp engine that would have been! Vance
This engine was way too bulky for an aircraft. It consumed all the under hood
space of a large car. A 400 HP V8 would be half the volume and get much better
mileage. Regen turbines are widely used in power plants. If they were practical
in aircraft they would be in aircraft :) I think they are also used in
the M1 Abrams main battle tank.
