Pumps are known to be distinct from
To pump, an engine must to be added to drive the pumping device?
Not any more, as the Quasiturbine completely integrates pump and engine concept!
Quasiturbine Pumps / Compressor
In the pump mode, a Quasiturbine driven by an external motor has 2 intakes and 2 exits
related to 2 quasi-distinct circuits. Each circuit can be used as vacuum or pressure pump,
for compressible or non-compressible fluids. The Quasiturbine is a positive displacement pump, and
does not make use of aero- or
hydro-dynamic flow consideration. Possible absence
of check valve is of considerable interest in many applications.
Because each Quasiturbine has 2 quasi-independent circuits,
one can be used in pneumatic, steam or hydraulic motor mode,
while the other is used as vacuum or pressure pump. In such a set-up, no
external motor is needed to drive the Turbo-pump. There is no need of a central
shaft either. Possible absence of
check valve is of considerable interest in many applications.
Since the 2 circuits share the moving pivoting blade rotor surface, this mode is
mainly suitable to applications where the fluid contamination between the 2
circuits causes no problem, or for uses as vacuum pump. In this mixed mode, the
Quasiturbine is at the same time the turbo-engine and the pump and has no shaft
in the center, the engine circuit being pressurized at its intake port and the
exhaust exit being 90 degrees away. The other pumping cycle intakes by the
following port and expels at exit 90 degrees further away.
An optimized turbo-pumps is derived from the standard Quasiturbine engine with
minor manufacturing modifications.
Why is it superior?
Less inertia limitation:
Reciprocal pumps reverse the flow while they pump, which is a severe inertia,
turbulence and heat generation limitation to high rpm. Because the flow is
peripheral and nearly unidirectional, the Quasiturbine is much less sensitive to
flow reversal and heat generation, which improves its efficiency.
Check valves are
generally preferable only when used with compressible fluid, but the
Quasiturbine could as well works without it. Check valve is never required with
incompressible fluid like liquid, which is of considerable interest in many
applications. The Quasiturbine in motor or pump does not produce vibration.
Compared to other rotary or piston pumps, the flow of the Quasiturbine is
relatively more linear in relation to the shaft angle rotation, which makes
it a better fuel flow controller...
High flow rate:
When the 2 circuits are used in pump mode, each blade expels its chamber volume when
reaching on the top and the bottom, twice per rotation. Since there are 4
blades, the flow is of 8 chambers per rotation, which is more that 60% of the
total rotor volume for certain geometry.
The Quasiturbine is well suitable in the 0 to few thousand RPM range, and
consequently the wearing is moderated. The acceleration and flow modulation are
also under control.
Efficient at any flow rate:
Contrary to aero- or hydro-dynamic pumps which have an efficiency curve
limited to a rather narrow range (outside of which those pumps heat considerably
the liquid or the gas), the Quasiturbine pump conserves a high efficiency on a
wide range of rotational regime. At zero RPM, this pump could completely cut the flow.
High pressure output:
Because of its robustness and very high geometric compression ratio, the Quasiturbine pump can deliver
a quite high
the previous reasons, the Quasiturbine pump and turbo-pump are breakthroughs and
open the door to new optimization of present and future devices.
Pistons and Wankels have:
- Dead times where the flow has to stop completely.
- The mass flow direction reverse in piston (not as much in the Wankel).
- They are limited in speed for these reasons.
Turbines have these advantages:
- Continuous flow at intake and exit.
- Single flow direction (no alternate mass direction).
- Higher rotational speed (flow capacity).
But both Piston and Turbine:
- Need two units, one engine to power and one pump.
- Flow is not quite linear with RPM.
- They are leaking fuel circuit at low RPM.
- Top efficiency (power and pump) occurs only at one design speed.
Quasiturbine is somewhat analogue to pump-turbine, because:
- It has quasi-continuous flow at intake and exit.
- Mass flow direction is not alternating but nearly unidirectional.
- Few rotational speed limitation in comparison (for higher specific flow capacity).
Further advantages of the Quasiturbine are:
- At rest, it is a closed pump circuit (turbines leak).
- Flow control is easy, quite proportional to rpm.
- A single rotor can simultaneously be used
as a power circuit
and as a pump circuit, removing shaft coupling and alignment.
- A real turbo pump!
(notice the 2 intakes and the 2 exhausts,
saving weight an volume).
- Several thousand HP pump is feasible in compact high pressure unit.
- Top power and pump efficiency at all RPM.
- Plastic or ceramic units can be without any radar signature!
From the basic QT75SC 75 cc per chamber engine bloc,
a turbo-pump prototype has been built making use of 2 parallel
motor and pump circuits of 300cc per revolution each, pumping a total of about 1,5
cubic feet per minute at 100 rpm (non-compressible fluid - zero psi differential).
The Quasiturbine is a very compact and light device, without power shaft, which
allows to pump large volume with the flexibility of pneumatic propulsion which
self adapt to torque variations without damaging the equipment. Absence of check
valve is of considerable interest in many applications. In the underground mines
and on explosive construction worksites, it could be used to pump water from
The Quasiturbine used in steam turbo-pump mode is well suitable to pump water
system condensate directly from steam pressure applied to one of its 2 circuits.
In pump mode, the Quasiturbine gives a nearly linear flow with the rpm on quite
a large range, which
makes it a precise flow valve or dosimeter for the chemical industries, or
eventually as a powerful rocket fuel injector and mixer driven by the combustion
gas itself... In application like rocket fuel Quasiturbine turbo-pump, the engine
cycle can be pressurized by the combusted gas, while the pump cycle handling fuel, the
contaminated engine mode exit being injected into the post-combustion. Notice
that the flow rate is controlled by the RPM, but the fuel exit pressure is
controlled by the gas pressure at the engine circuit intake, a very
interesting characteristic in the case of rockets application.
Refrigeration: Adsorption Refrigeration Engineering Thermal
Physics. Conventional pressure regulators make all the gas to
expand from the constant high pressure side, and the gas pressure-kinetic energy
at the needle is converted into undesirable heat, reducing accordingly the
amount of cold produced. The Quasiturbine rotary expander allow for individual
chamber to expand at a variable reduced pressure during expansion, and such
reduces the gas kinetic energy transformation into destructive heat.
Furthermore, the Quasiturbine recuperates mechanically the gas differential
pressure energy, which can be used to run more compressors and make more cold...
A double energy efficiency gains! A single Quasiturbine in tubo-pump (tubo-compressor)
mode could have one circuit used as rotary expander while the other is used to compress back some of the expanded gas. This offers great enhancement of thermodynamic
cooling machine, and specially in high power LNG - Liquid Natural Gas
liquefaction stations. Of course, this efficiency enhancement is also available
for more modest cooling system and air conditioning equipments.
Quasiturbine Theory Concept
Quasiturbine Rotary Expander