Quasiturbine Aviation 

Propeller airplanes:
Multi-fuel air-cooled ultra-light 

In a propeller airplane, weight reduction allows a larger payload or longer autonomy,
space saving allows to reduce the aerodynamic drag,
absence of vibration increases instruments reliability, photos quality and flight comfort,
the noise reduction increases the discretion level,
the high torque allows the use of multi-blades propeller
and the better intake characteristic of the Quasiturbine allows higher flight altitude.
Since the Quasiturbine has an empty center, the shaft can be attached to the airplane wing or frame
with its axial thrust bearing and its propeller independently from the engine, 
which simply slide on this shaft, and can easily be removed for service
(furthermore, if the propeller hits an object, 
the shaft can be damaged and replaced without the Quasiturbine engine being affected).
Finally, because the engine is longitudinally shorter that piston engine,
the airplane nose can be substantially shorten, and the propeller be closer to the center of mass
with great advantage on all sort of vibrating forces generated by a far away propeller...

In an helicopter, a large diameter Quasiturbine could generate enough torque
to directly drive of the rotor blades without any gearbox,
while making much less noise.

Note on the low sensitivity of the Quasiturbine to thermal shock:
The high sensitivity of air-cooled piston engine to thermal shock (which reduces its reliability in aviation)
results from the fact that the piston interior is cooled by a flow of cooling oil that stays hot,
while the cylinder is cooled by an air flow.
The air-cooled Quasiturbine is much less sensitive to thermal shock,
since both the stator and the rotor are cooled by an air flow and react simultaneously
the same way.

Engineering of a small air-cooled Ultra-light ULM Quasiturbine engine QT600
in the range of 70 to 100 HP is in part completed.

Construction of an experimental prototype will be a priority... when combustion comes commercial.

Hybrid Quasiturbine-Fan (or Quasiturbine-Jet) 
No temperature limit in the jet nozzle!

Note for non initiated :
The magic of turbine airplane engine
Here a way simple to look at the turbine engines.
Suppose a rectangular box of 12 in. by 12 in. of section by 5 feet length.
Suppose that there is a magic device inside which does not add pressure at the entry section,
but add a pressure of 100 psi to the exit section.
You will then have a displacement of the box, but with which force?
Hold well, because if 100 psi is not a strong pressure,
the 12po X 12po gives 144 square in. X 100 = 14,000 pounds!
If the box is attached to a plane, there will be 14,000 pounds of push during the 6000 feet of runway,
and you will be supersonic on takeoff!
If the pressure were only 10 psi, you would have already 1,400 pounds of push,
what is much more than a small Cessna!
Conclusion, the pressures in the gas turbines are not considerable, although the speed of gases is.
This simplification is not perfect, but useful...

Air motor power can be increased if heat is given to the air to further increase its volume
and strongly reverse the negative adiabatic cooling, providing the air motor can accept this kind of hot air ?
This was the idea of Joule (also Brayton) when the designed their cycle of turboshaft jet engine !
The best way to add heat to air between the compressor or the storage air tank
and the air motor is to inject the fuel into that same air flow and burn it insitu.
To accept that hot air/gas flow, conventional hot turbines have been developed,
and similarly, Quasiturbine hot air motor could be developed as well...
with efficiency and power modulation advantages over conventional hot turbines.
Turboshaft jet engine are noting else than large air heated motors carrying their own compressor !
One of the most efficient and high specific power engines of all time !

In Brayton mode, the aerodynamics of conventional compressors present risks of blade stall
which generate the abrupt interruption of engine (flame out) with important structural damage.
The Quasiturbine compressors remove completely the compressor stall risk,
and they can be very elongated along the shaft to reach flows comparable with the aerodynamic compressors,
although turning at a much lower speeds.
Considering the high power density, the low cross section area and the exceptional intake characteristics of the Quasiturbine,
it is reasonable to expect to conceive an airplane engine :

1) Quasiturbine-Prop 
in which the propeller would be driven by a Quasiturbine,

rather that by a conventional power turbine. 

2) Quasiturbine-Fan 
in which the Fan would be driven by a Quasiturbine,

rather that by a conventional power turbine. 

3) Quasiturbine-Fan Hybrid 
in which only the compressor (also a Quasiturbine) would be driven by a Quasiturbine,
leaving all the reactor energy available to drive a still more powerful Fan.
The Quasiturbine air intake could come from the compressor.
The empty center of the Quasiturbine would allow the shaft to go from the power turbine to the fan, 
as well as the compressed air.

4) Quasiturbine-Jet reactor (no hot turbine)
Still more revolutionary would be a Jet Reactor without power turbine in the hot gas flow,
where the compressor would be driven by a Quasiturbine, leaving to the Jet all its propulsive energy
The Quasiturbine air intake could come from the compressor.
In this last case, the suppression of the conventional power turbine 
would permit to operate the engine at much higher temperature without risking to melt the non-existent power turbine,
and would permit to substantially increase  the speed and the efficiency.
This airplane engine would operate in the same mode as the rocket engines!
For still a higher power density, 
the Quasiturbine could be fueled in pneumatic mode in hydrogen peroxide. 
Those concepts would also permit to construct much less complicated airplane engines 
and at a much lower cost than conventional turbines.

5) Two Quasiturbines in series (in pneumatic mode). 
A reactor without Jet!

Power produced from pressured gases is proportional to (pressure) X (the flow).
In the piston and Quasiturbine, power is produced by pressure increase during combustion,
while in the Brayton cycle, the pressure is constant,
and the power is produced by an increased gas flow during combustion.
The "Brayton Cycle" (also known as Joule Cycle) of the turboreactors. 
uses the intermediary transformation of pressure energy into kinetic energy, 
which allow later the kinetic energy recovery at the same pressure that the chamber intake. 
The Quasiturbine is pressure sensitive and requires a higher pressure at intake than at exit, 
because it does not use kinetic energy transformation.
Nevertheless, two distinct Quasiturbines space away on the same shaft 
sharing a common pressure in between may be linked through an external combustion chamber (combustor) and looped (?)
(If the first one is a cold high pressure low flow rate, the second one will have to be a hot low pressure high flow rate,
providing that some combustion comes in, to increase the flow at constant pressure like in turboreactor).
Finally, from a high pressure source like in jet airplane conditioning system, 
a Quasiturbine compressor could be link with a Quasiturbine pneumatic motor 
through a cooling heat exchanger to act as a heat pump.
In Brayton cycle, the pressure is the common denominator between the compressor and the power stroke (power turbine).
Since the combustion increases de volume of gas without any change in pressure,
the power flow in the hot Quasiturbine has to be much more important than the intake flow trough the compressor.
Using the two independent circuits in a single Quasiturbine would be great,
but because it would impose a same flow at intake and exit, it would not produce net energy output.
By using 2 QT, a small one as compressor, driven by a larger hot one at exit, would however makes it a net energy output engine.
Note that both Quasiturbines could in fact be of the same size providing the QT compressor RPM rotates at lower RPM,
though a gearbox coupling, than the the hot power QT.
But suppression of the gearbox is highly desirable improvement over conventional gas turbine,
and can be simply done by using different sizes Quasiturbine !
For a simple example of this cycle apply to heat process, see www.starrotor.com 
which also could in principle rely on 2 Quasiturbines of different sizes.


It is anticipated that the Quasiturbine, specially in photo-detonation mode,
would permit a substantial improvement in aeronautical propulsion,
and would constitute a complement to pulsed detonation of the future.
See - The Pulse-detonation Engine for airplane propulsion by Jim Kelly
in Popular Science Magazin Septembre 2003 at :

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Quasiturbine Aviation Inc., Promotional Agent for the Quasiturbine Continuous Combustion Rotary Engine or Compressor
Casier 2804, 3535 Ave Papineau, Montréal Québec H2K 4J9 CANADA (514) 527-8484 Fax (514) 527-9530
http://quasiturbine.promci.qc.ca             quasiturbine@promci.qc.ca