Quasiturbine> Advantages> Integration


Application advantages could be as precious as intrinsic engine ones.
Innovative engine integration leads to economic and human benefits.
The Quasiturbine can further open new areas of unforeseen applications.

Quasiturbine Integration

Matching Engine With Application

Engine efficiency is a large domain of activity which extends far beyond engines. For example, the presence of an engine in a vehicle adds accessories and weights which have to be carried by the power of that same engine (the net usable power is reduced by the presence of the engine itself). The presence of the engine is a necessity, but also a factor of inefficiency. The ideal vehicle would not bother to have an onboard engine! This is to show that not only engine efficiency is important on the bench test, but must also reduce to the minimum its self-inefficiency in application.

It would be worthless to have a 70% efficiency gas engine for mobile application, if such a 30 HP engine would weight 3 tons! However, this could still be valuable for stationary applications. Engine needs to be properly match in all application, and the most versatile wins!

QT Particularities

Quasiturbine engines are simpler, and contain no gears and far fewer moving parts. For instance, because intake and exhaust are open ports into the walls of the rotor housing, there are no valve or valve trains. This simplicity, small size and weight allow also for a saving in construction costs. Because its center of mass is immobile during rotation, the Quasiturbine has very little or no vibration. Due to the absence of dead time between strokes, the Quasiturbine can be driven by compressed air or steam without synchronized valve, and also with liquid as hydraulic motor or pump. Other advantages include high torque at low rpm, combustion of hydrogen, and compatibility with detonation mode in Quasiturbine with carriages. Pneumatic and steam optimum efficiency independent of the rpm and the load is also quite a unique characteristic.

Typical comparison:
Engine displacement
versus the Total engine volume

4 strokes engine type         Unit displacement         Engine volume

Piston                                  1                         15 to 20
Wankel                                1                             5 to 7
Quasiturbine                        1                          1.3 to 2

The Quasiturbine is a positive displacement turbine
with a total displacement almost equal to the engine volume

(Imagine one day, a 3 liters car engine into a 3 liters volume!)


Efficiency Considerations

Not all engines are or need to be equally efficient. A military strategic application may require an engine lifetime to be only few seconds, and not care about efficiency. At the opposite, a space craft Stirling engine may command for extremely high efficiency. Generally, economic considerations balance the value of the engine with the value of the energy flowing into it over its lifetime. This command substantial efficiency for automotive or stationary applications having high use factor over years.

Since the efficiency is closely tied to the application and cannot be fully appreciate outside a specific integration, the efficiency criteria is not always obvious to apply. For example, one of the paradox of today hybrid vehicle concept is: How much additional equipment can be added to a vehicle to reach the point where this equipment has worthless net saving effect in actual application? In many applications, torque, rpm, or power modulation capability become a dominant criteria.

Engine Exhaust Heat Recovery:
By placing a hot Quasiturbine into or around an engine exhaust pipe, and injecting pressurized hot water (steam keep in the liquid state for better heat transfer), some heat can be recovered into mechanical energy. Stirling and short steam circuit Quasiturbine could do similarly!

High Torque Versatility

Several engines may match in power, but not in rpm or torque. Gas or steam turbines may rotate over 10,000 rpm, but if the user needs the power at 900 rpm, an other kind of engine may be more suitable?

Human need is generally low rpm. For example, a car wheel on the highway turns around 800 to 1400 rpm. Gearbox are used to match torque and rpm with engine, but they are costly, sensitive, heavy, energy consuming and maintenance intensive... There is a strong demand for high torque at low rpm, a condition not easy to produce directly within an engine. The Quasiturbine is exceptional in this regard.

Power Modulation capability

Contrary to the conventional turbine, pneumatic and steam Quasiturbine optimum efficiency is optimum in a large gap of rpm and load, which is also a quite unique characteristic highly in demand in the world of engine. For solar steam plant for example, the same Quasiturbine driven generator can work efficiently at peak power, as well as at overnight idle power, or at variable sunny conditions!

Light and Compact

Airplanes. Nowhere a high specific engine power is so welcome. Zero vibration is also a great advantage to reduce fatigue and instrument failure in airplanes. Compact engine also means a reduce drag cross-section and faster planes. The Quasiturbine is also most suitable for portable tools, generator...

Vehicle also benefits from the light and compact characteristics of the Quasiturbine, which permits new innovative layouts and power train setup (Because the Quasiturbine can run in all orientation, it could be mounted straight on a differential shaft oriented upward, or better, concentric to the wheel shaft because the Quasiturbine center is free of any mechanism).


Where environmental conditions command a zero pollution engine, the pneumatic and steam Quasiturbine can provide a practical solution, like inside-shop, or in underground mines.

Vibration is an important environmental factor for hand tools like chainsaws, which the Quasiturbine can reduce to zero.

Multi-fuel is also an environmental consideration in countries where gas and diesel is not currently available, or where imports are out of price.

New Areas

Because the Quasiturbine center is free and available, lets insert a jet boat propeller inside of it, and because the Quasiturbine has no oil pan, it could be submerged to provide direct underwater boat or recreational propulsion.

A small submarine innovative pneumatic Quasiturbine concept could have a cabin free of any propulsion component, where the air tank is droppable below, the propulsion Quasiturbine is at the rear, and the air exhaust of the Quasiturbine goes into the cabin to be inhaled by the crew.

The pneumatic engine does not show any vibration on the shaft. As an example, a chainsaw with a pneumatic engine (running from pressure air bottle regulated to less than 100 psi) allows for a non combustible "all condition" running unit for the fireman and national safety teams. It does run in heavy smoke or under water as well. Exhaust can even be inhaled by the fireman ! A must for all civil defense organization ...

Because the pneumatic and steam Quasiturbine have 2 distinct flow circuits, one can be used as motor by injecting pressure air or steam, while the other is free for pumping whatever gas or liquid present at the intake. This is a turbo-pump configuration where the motor and the pump are a one perfectly integrated unit. In this mode, the Quasiturbine center is left empty as no shaft is necessary...

Fuel cell needs good cooling. Why not use liquid nitrogen which could evaporate and expands into a pressure exchanger and feed a pneumatic Quasiturbine to produce additional electricity? This way, the Quasiturbine and the fuel cell make the perfect marriage...

Hybrid Quasiturbine-Fan (or Quasiturbine-Jet) offers potential for no temperature limit in the jet nozzle! 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 new airplane engines.

Out of space short steam circuit or Stirling Quasiturbine can be made in the shape of a large and thin sandwich like disk, which oriented toward the hot sun can provide power by temperature difference.

Engine Exhaust Heat Recovery: By placing a hot Quasiturbine into or around an engine exhaust pipe, and injecting pressurized hot water (steam keep in the liquid state for better heat transfer), some heat can be recovered into mechanical energy. Stirling and short steam circuit Quasiturbine could do similarly!

Much more innovative concepts flow from the Quasiturbine geometry.

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