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APUQ Zero Pollution QT Pneumatic Car

Disclosed on September 25, 2005
Video 350 Kb at:

May 2006 - TV news at LCN and TVA

APUQ Pneumatic 12 volts alternator
The objective is to have an alternator on each side do the QT!

A similar Steam Generator is also in project

Engine Exhaust Heat Recovery

Better than hybrids? Recovering 30% of the engine exhaust heat would allow to exceed most hybrid efficiency performance. 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. A Quasiturbine Stirling or short steam circuit could do similarly! See: Engine Exhaust Heat Recovery with Quasiturbine

Applicable to Solar Heat

The concept of Quasiturbine Solar Steam

The Quasiturbine researcher team has initially established a list of 30 conceptual piston deficiencies and as many Wankel deficiencies . The Quasiturbine general concept is the result of an effort to improve both engines by suppressing the limiting sinusoidal crankshaft and offering up to 7 degrees of freedom at design.

Quasiturbine Definition

The Quasiturbine (Qurbine) or Kyotoengine is a pressure driven continuous torque deformable spinning wheel; a no crankshaft rotary engine having a 4 faces articulated rotor with a free and accessible center, rotating without vibration nor dead time, and producing a strong torque at low RPM under a variety of modes and fuels. The Quasiturbine can also be used as air motor, steam engine, Stirling engine, compressor and pump. The Quasiturbine is also an optimization theory for extremely compact and efficient engine concepts.

The Quasiturbine is at the crossroad of the 3 modern engines: Inspired by the turbine,
it perfects the piston, and improves upon the Wankel. The Quasiturbine is universal in relation to energy sources: Liquid and gaseous fuel, hydrogen, steam, pneumatic, hydraulic... The Quasiturbine engine was invented by the Saint-Hilaire family and first patented in 1996. The engine makes use of a complex computer calculated oval shape stator housing, creating regions of increasing and decreasing volumes as the rotor turns. It is capable of burning fuel using detonation, the optimal combustion mode of the future... the piston cannot stand.

How it Works

In the Quasiturbine engine, the four strokes of a typical cycle de Beau de Rochas (Otto) cycle are arranged sequentially around a near oval, unlike the reciprocating motion of a piston engine. In the basic single rotor Quasiturbine engine, an oval housing surrounds a four-sided articulated rotor which turns and moves within the housing. The sides of the rotor seal against the sides of the housing, and the corners of the rotor seal against the inner periphery, dividing it into four chambers.

combustion cycle

Intake (aqua),
Compression (fuchsia),
Combustion (red),
Exhaust (black).

A spark plug is located
at the top (green)

As the rotor turns, its motion and the shape of the housing cause each side of the housing to get closer and farther from the rotor, compressing and expanding the chambers similarly to the "strokes" in a reciprocating engine. However, whereas a four stroke piston engine produces one combustion stroke per cylinder for every two revolutions, the chambers of the Quasiturbine rotor generate height combustion "strokes" per two rotor revolutions; this is eight times more than a four-strokes piston engine.

Because the Quasiturbine has no crankshaft, the internal volume variations do not follow the usual sinusoidal engine movements, which provide very different characteristics from the piston or the Wankel engine. Contrary to the Wankel engine where the crankshaft moves the rotary piston face inward and outward, each Quasiturbine rotor face rocks back and forth in reference to the engine radius, but stays at a constant distance from the engine center at all time, producing only pure tangential rotational forces.

The four strokes piston has such a long dead time, its average torque is about 1/8 of the peak torque, which dictate the robustness of the piston construction. Since the Quasiturbine has not dead time, average torque is only 30% lower than the peak torque, and for this reason, the relative robustness of the Quasiturbine need be only 1/5 of that of the piston, allowing for an additional engine weight saving...

Turbine Comparison - Competitiveness

The Quasiturbine share with the conventional turbine the most valuable characteristic of torque continuity (even if not constant, there is no propulsive dead time), that very few other engine concept offer. Being a balanced configuration with near zero seal movement machine, nothing prevents the scaling up of the Quasiturbine to the 10 megawatts range or more. Contrary to complex conventional turbines, the Quasiturbine are competitively down scalable to low power units, easy to operate, and do not require as sophisticated trained maintenance personnel.

Hydraulic, pneumatic, steam, gas and fuel combustion... produce primary energy in the form of expansion and pressure. Being an hydro-aero-static device, the Quasiturbine directly transforms this pressure energy into mechanical rotation motion with optimum efficiency, whatever low or high is the pressure (QT idle with only a few psi !). Conventional turbines are hydro-aero-dynamic, and they cannot handle directly the energy of pressure which must be converted into kinetic energy. For a given geometry, the efficiency of conventional turbine falls rapidly if the flow velocity moves away from the optimum.

Because the Quasiturbine does not require the pressure energy to be converted into the intermediary form of kinetic energy, it has numerous advantages over the conventional turbines, including on the efficiency at all regimes.

A conventional turbine is so demanding in term of flow control, rpm and load, it has to be the central dominant equipment to which all other system application components must be slaved. In contrary, the Quasiturbines can be efficiently slaved to a variety of different applications.

Quasiturbine Solution

Detonation and hybrid are two different means to harvest the low efficiency of reduced power piston engine, and both are compatible with efficient electrical (in-wheel) power train. Detonation engine is however a more direct and efficient way, and because the « on board fuel » is already a form of energy storage, detonation engine avoid to re-stock this energy electrically into batteries. The chemical energy stored in the fuel is degraded when chemically re-stored in batteries.

Many researches are going on to increase energy efficiency on the long term with piston, hydrogen, fuel cell... Hybrid concepts are ways to harvest part of the "low power efficiency penalty" of the piston engine used in vehicle, but counter-productive measures limit the long term perspective until they could efficiently fuel from the electrical grid. None of these solutions are short term stable and competitive.

The Quasiturbine in Beau de Rocha (Otto) cycle is a relatively simple technology which could be widely used within a few years with substantial efficiency benefits over piston engines in many applications. Large utility plants convert energy more efficiently than small distributed units and should be favored when possible, but on the long term, the Quasiturbine detonation engine is one of the very few means to match utility efficiency the distributed way, while being as chemically clean as possible. Not only the photo-detonation suppresses the energy consuming butterfly vacuum intake valve and so preserving the engine efficiency at low power, but since it requires a much higher compression ratio, it does increases the engine efficiency at full throttle as well.
QT-AC (With carriages) is intended for detonation mode,
where high surface-to-volume ratio
is a factor attenuating the violence of detonation.

The next step in world engine research is to make the gas engine as efficient as the diesel engine, and the diesel engine as clean as the gas engine. The photo-detonation Quasiturbine AC does that and more, by conciliating both gas (homogeneous) and diesel (non-homogeneous) engines in one extremely efficient and clean photo-detonation mode, leading the way to a major efficiency breakthrough! Photo-detonation permits 2 efficiency gain improvements: The removal the butterfly intake vacuum valve (engine compression breaking - which exist at all time within gas engine), and the increase of the compression ratio (well over the knocking and the diesel level). Because the combustion is homogeneous and occurs in excess of air, it is as clean as an external combustion.

Not to confuse the ignition process (the sparkplug and the diesel thermo ignition)
with the combustion mode (thermal wave or detonation)
Notice there is no detonation in diesel engine.

Photo-detonation self-fires similarly to Diesel,
but burn homogeneously, faster and cleaner.
This mode uses a « fast detonation chamber »
instead of a « combustion chamber ».

Quasiturbine has extra degrees of freedom allowing for thermodynamic and photo-detonation optimization, which other simplified mathematical concepts like piston or Wankel can not pretend. By opposition to dozens of new engine designs, the most important at this time about the Quasiturbine is the fact that it does unknot a new field of development and offers means to achieve what no other engine design has suggested or is able to, and specially for detonation where piston engine has failed for over 40 years...

Why a Better Engine?

In their book about the Quasiturbine , the inventors have used a set of 14 engine parameters to show than none of the modern engine meets simultaneously all the optimum general demanding criteria. Engines fail to be "all in one" compact, low weight, low noise, zero vibration, high torque at low rpm, efficient on a wide power range... While having homogeneous clean combustion and being multi fuel capable... With our today's Beau de Rocha (Otto) mode piston gas engine, about half the gasoline used in the transportation sector is literally wasted to fight the intake atmospheric vacuum depression generated by the carburetor or injector manifold butterfly-valve (The engine-braking effect). This is half the pollution of the transportation activities!

Engines are at the end of the energy chain, and their pollutions affect the most immediate users environment. Better engines are keys to better environment, not only because of their own improved efficiencies, but also because any bit of improvement has directly amplified impacts on all anterior stages of the energy cascade and industry. This is the reason for Quasiturbine!

Last Drops of Fossil Fuel?

If one day we are going to limit the availability of fossil fuel, in which type of engine would you put the precious liquid ? Without a doubt in the most efficient and clean engine. It is important to develop better engines regardless of the abundance or the rarity of the fossil fuel, to attenuate the effect of the inevitable transition and in the perspective of the precious synthetic replacement fuel. The efficient engine development is part of the measures intended to better prepared ourselves to tackle the future... Closer we will get to the end of the fossil era, more the performing engines will be necessary and appreciated!

Fossil Fuel and Renewable Energy

The comparison is somewhat unfair. First, fossil fuel comes from pumping an underground reservoir – it is not man-activity stored energy. Second, comparing text book fossil fuel energy contain of about 9000 W-h/Kg with renewable energy systems is further unfair. One Kg of fossil fuel contains “no energy at all, if you do not have oxygen to combust it - on the moon for example”. For mobile applications, the truth is that to combust a typical car gas tank, one need about 2 tones of oxygen, which is taken out of the environment while underway… but should be onboard for matter of fair energy comparison with renewable systems like mechanical coil spring, compressed air, batteries or liquid nitrogen… Amazingly, both the fossil fuel and solar panels systems fail to offer a fair « onboard total energy system » comparison in mobile applications. Just keep that in mind for the evaluation of the future generation of projects…

An Engine and more

The Quasiturbines are highly suitable for many « traditional systems » like heat pumps (refrigerators, freezers, air conditioners), pneumatic energy storage, air compressors and water pumps, hydraulic pump and motor, turbo-pumps, as well as in utility co-generation, aviation, marine or locomotive propulsion, Combined Cycle Gas Turbines, Rotary Pressure Expanders for Gas Pipeline Pressure Energy Recovery or as industrial and nuclear boiler steam vapor energy production or recovery...

Not only the Quasiturbine can be used as a pneumatic (air) or steam co-generation engine, but it can run in internal combustion Otto mode and photo-detonation mode, in Stirling thermal, Brayton and other cycles. This makes it suitable for cogeneration and conventional engine exhaust heat recovery (see QT Type Stirling) , or for hydro-electric water dams (see QT Type Hydraulic).

As a rotary expander, it can be used to recover MW of pressure energy at gas pipeline pressure reduction stations (or steam pressure reduction stations), and to efficiently replace the expansion valve in more ecological refrigeration and heat pump air conditioning systems (removing the mechanical pressure energy which destroys the cooling efficiency), while offering compression capability. See

Engines in Energy Strategy

The future of energy strategies involve resources, efficiency, distribution and mobility. Because large utility energy station transforms fuel into electricity with a higher efficiency than the small distributed stations or your car engine, there will be a period during which hybrid, fuelcells (also thermal machines), batteries and electricity from the grid (electric power train will still be suitable with onboard efficient generator) will tend to substitute internal combustion Otto engines. However, as more efficient and photo-detonation engines will come on the market, and small engines will become as efficient as large utility stations, this kind of substitution will have no reason whatsoever. Only then, distributed electric generation will become reality, and because of fuel mobility specific energy and power advantages, efficient internal combustion engines will then have no substitute!

Still the resource will have to be addressed, but the most likely efficient solution will be toward SYNTHETIC FUEL (from bio-solar ... or nuclear) similar to conventional fuels, because the best and most convenient way to store hydrogen is to bond it with carbon atoms and make a conventional liquid fuel (will we then enter a carbon depletion era?). For these reasons, no foreseen technology is on the long term going to substitute efficient combustion engines... toward which research and development must continue. Those saying that today improved thermal internal combustion engines come to late in time are missing the point: If thermal engines were more efficient, no one would talk about hybrid and hydrogen...

Environmental Concerns

Quasiturbine is also accessible via

In his forward statement of December 15, 2003 about the Quasiturbine White Paper, Mr. Myron D. Stokes, wrote :

In the context of the international environmental and resources depletion discussions such as the Kyoto Accord, and taking into account the general population conviction that climate changes are currently endangering our planet, there is a new sense of urgency mandating that no energy technologies can be discarded, and this is particularly true of any sound engine concept breakthroughs. The Quasiturbine technology is among the very few energy and environment tools we have to address our present concerns, and one precious new means available to improve our vital collective objective.

It goes without saying that acknowledging its existence may fall into the realm of a social obligation.

How Can You Participate?

At this time, priority goes to small power plan and demonstrations based on engines already available. You can participate by contacting local college or university (mechanic, environment or energy department) and invite them to initiate a Quasiturbine study or project. Willing to do more? Sponsor their project, share the use of the unit and follow-up the results... This way, you will involve the young generation of your area in an emerging technology in which they will likely play a role, while supporting your local community in its search for environmental and energetic solution of the future.

Looking for a Gift Idea?

Offer the Book - La Quasiturbine Écologique (ISBN 2-922888-00-2)
A 292 pages book in French on engines, their secrets and improvements.

More Technical

Papers About QT

In the Medias

Engine problematic

Why is the Quasiturbine (Qurbine) so exceptional?

White Paper on the Quasiturbine Technology

Regional Interest

Quasiturbine and in-wheel motor, see


APUQ - Association Québécoise de Promotion
des Usages de la Quasiturbine (Québec)
Site initial :
Site suivant :

OQAPA - The Ontario Quasiturbine Application Promotion Association

CRPDQ - Coalition Régionale de Promotion
et de Développement Quasiturbine
(Saguenay Lac Saint-Jean, Québec)

QEEAL - Quasiturbine pour l'Économie et l'Écologie
de l'Amérique Latine

AFPUQ - Association Française de Promotion
des Usages de la Quasiturbine (France)

Discussion Groups

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Youtube Video Channel Quasiturbine

Quasiturbine Explained Simply  

The Quasiturbine at the invention autopsy:
  A bibliographic overview prior to 2012
Youtube Video Channel Quasiturbine

Website before December 2004 (not maintained)

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