Quasiturbine - A New Approach
Quasiturbine Definition
The Quasiturbine (Qurbine) is 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.
Quasiturbine
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
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.
QT-AC (With carriages) is intended for detonation mode,
where high surface-to-volume ratio
is a factor attenuating the violence of detonation.