quasi-turbine combustion engine

8/7/2019 Quasi-Turbine Combustion Engine

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Quasi-turbine

Document By

SANTOSH BHARADWAJ REDDY

Email: [email protected]

Engineeringpapers.blogspot.com

More Papers and Presentations available on above site
mailto:[email protected]:[email protected]


2/17

ABSTRACT

In this paper a rotary internal combustion engine, Quasi-turbine is discuss

this, rotary motion is generated through the combustion of the fuel, unlike the pist

converts reciprocating motion. It is a modified form of Wankel engine. This paper explains the

salient features of Quasi-turbine, its working, the combustion process involved, and the v

of applications in detail.

The peculiarity of Quasi-turbine is in possessing of four combustion chambers, all of which

participate in combustion in each revolution. That means in just two revolutions of the rotor, there are

32 strokes, out of which 8 are power strokes. It has its existence in two forms

(with carriages) and QT-SC (with out carriages). The volume of the combustion chamber depends

on the movement of the internal parts. This is the basis of the suction, compression, expansion and

exhaust processes.

The ordinary combustion processes like flame propagation, auto-ignition, HCCI cannot

burn the complete fuel because of the peculiar geometric shape of chamber. Hence

detonation, a consequence of detonation is utilized, in which radiated waves released from

detonation process will burn the fuel even at inaccessible parts. It eliminates the usage of anti-

detonating agents.

Quasi-turbine has a wide range of applications like pneumatic engines, steam e

compressors, pumps, chainsaws, air cars etc., It overcomes all the drawbacks of

engine. It overcomes the inertia of various parts like crank shaft, valves, and cams of a reciprocating

engine and improves the efficiency. It has various superiorities over Piston engine and Wankel

engine which are explained later in detail. Till now a variety of products like QT600SC, QT75SC, QT

chain saw, QT air car are manufactured and being tested.

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Quasi-turbine

INTRODUCTION

At first the internal combustion engine found was a rotary combustion

namely Wankel engine. But till now the reciprocating piston engine has appeared to

operational than any other. But a rotary combustion engine developed by the improvement of Wankel

engine is now going to show better performance than the piston engine avoiding the limitations of the

original piston engine. It is Quasi-turbine.

The engine uses a four-sided articulated rotor that turns within a complex computer calculated

oval shape creating regions of increasing and decreasing volumes as the rotor turns. The Quasi-turbine

design can also be used as an air motor, steam engine, gas compressor or pump.

of burning fuel using photo-detonation, an optimal combustion mode of the future th

can not support...

HISTORY

At first the inventors found that when the turbine blades are attached one to an other in a

chain like configuration, the rotor acted as compressor for a quarter of a turn, and as engine the nextquarter of a turn... This is origin of the idea of Quasi-turbine. This was first invented by Saint-Hilaire

family and first patented in 1996.

Quasi-turbine Definition

The Quasi-turbine is a no cranksh aft rotary engine h

faces articulated rotor with a free and accessible center, rotating without vibration o

time, and producing a strong torque at low RPM under a variety of modes and fuels. The Quasi-

turbine design can also be used as an air motor, steam engine, gas compressor or pump. The Quasi-

turbine is also an optimization theory for extremely compact and efficient engine concepts.

BASIC PRINCIPLE

It is a rotary internal combustion engine having a deformable four

rotor which enables to create four different chambers inside the engine. The charge is

to enter through the inlet port into the combustion chamber. Then this charge is sub

Compression,

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Quasi-turbine

Combustion and Expansion processes. Then the residual gases are sent through the exhaust port.

The same sequence of processes happens in the other three chambers. Thus we can get 8 power

strokes out of two revolutions. The power strokes in each combustion chamber will rotate the shaft

due to the peculiar geometry of the rotor.

ENGINEERING CONFIGURATION

CONSTRUCTION

It is a rotary internal combustion engine. It is either circular or el

It is constructed in two ways.

1. QT-AC (with carriages)

2. QT-SC (without carriages).

QT-AC (with carriages)

The rotor is made up of simple a mechanical linkag

deformable volumes. In this there will be four carriages. Each carriage is connected to the shaft

through a peculiar geometrical shape. The rotor turns on the inner periphery of the stator through thedumb-bell shaped linkages. It has a fixed inlet and exhaust ports. The compression and expansion

processes in the QT depend on the movement of the carriages. If the carriages move inwards the

charge is compressed and if the carriages move outwards the pressure decreases.

QT-SC (without carriages)

The rotor is made up of simple

oval shaped lobes. In this there will be four

lobes. Each lobe is interconnected to each other.

Whenever the rotor rotates on the inner periphery

of the stator the volumes of the chambers will be

changed. The stator is elliptical in shape. So that

depending on their geometry the compression and

the expansion occurs. The each combustion

chamber is sealed from the adjacent ones by

perfect ceramic coatings.

QT-AC (with carriages) & QT-SC (with out carriages)

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Quasi-turbine

COMBUSTION PROCESS

PRINCIPLE

This combustion process uses detonation which is undesirable in

piston engines. Because of the detonation short pressure pulse is created. This creates a black

body type laser like radiation. Here the combustion is just like a paper burning under a focal lens

projected by sun light. The major thing here is the photons or black body waves released from the

process of detonation propagate through all the parts of combustion chamber and lead to complete

combustion and hence called Photo-detonation.

REQUIREMENTS

The combustion should be much faster in the sense that 8 combustion processes are to

be completed in two revolutions.

As the combustion chamber included b/n two carriages or lobes is peculiar, the combustion

process used should be able to burn the fuel even at inaccessible parts.

As there are 8 intake strokes per two revolutions the fuel required for combustion should bemuch less.

PROCESS

As the ordinary combustion processes like flame propagation, autoignition, H

cannot satisfy the above requirements there is a need to introduce a special process known as Photo-

detonation. This process can be easily understood as a paper burning under a focal lens projected by

sun light. This is so because the waves persisting of photons energy when focuse

high intensity at the tip and thereby the temp rises at that end. It can be easily understood as the

letter i. In general we will use anti-detonation additives to absorb the shock waves of detonation.

But these are UN necessary here because these waves are necessary for the photo-detonation mode of

combustion.

The sequence of process of photo-detonation proceeds as follows.

Ordinary wave front combustion (also called Deflagration)

Auto lit (hot spot triggering still deflagration)

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Quasi-turbine

Thermo lit (a very irregular process where several little pocket of mixture lit spontaneously

,but here inter-region goes deflagration)

Photo-detonation (there the compression temperature is high enough to generate

high concentration of black body radiation increasing as the power 4 of the temperature).

ADVANTAGES

Detonation in the QT occurs rapidly at top dead center. In the diesel engine, ignition of the

injected fuel occurs somewhat after TDC, so it is progressiv

mechanically protect the piston. The QT's power stroke is therefore somewhat longer "with

early and late mechanical energy conversion" and the exhaust somewhat cooler, which also

implies a more efficient engine.

This combustion process eliminates the usage of anti-knocking additives.

The Quasi-turbine (unlike the diesel) is therefore a clean homogeneous combustion engine.

It has virtually no emissions other than the standard products of combustion, e.g., CO2 and

H2O.

WORKING

It is a rotary internal combustion engine having a deformable four faced rotor which

enables to create four different chambers inside the engine. In each combustion chamber the normal

four strokes happens.

In QT-AC (with carriages) the movement of the carriages inwards and outwards.Let us

observe the four strokes in a single combustion chamber which are shown with arrows in the

following figure.

Suction Compression

Suction:

the

The charge (fuel and air mixture) is allowed to enter the combustion chamber because of

Outward movement of the carriages leading to reduction of pressure than the atmospheric pressure.

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Quasi-turbine

Compression:

The charge is compressed due to the inward movement of the carriages to a high pressure

and temperatures because of high compression ratios.

Expansion:

The high thermal energies released in the combustion chamber

into mechanical energies generating mechanical forces which pushes the carriages outw

there by rotating the rotor.

Exhaust:

Because of the inward motion of the carriages the exhaust is sent out through exhaust ports.

In QT-SC (with out carriages) the movement of the articulated lobed rotor in a vowel

shaped

stator creates varied volumes of the chamber.

Suction:

The charge (fuel and air mixture) is

allowed to enter the combustion chamber

because of the increased volume.

Compression:

The charge is compressed due to the

pressing of a lobe against the stator.

Expansion:

The high thermal energies released in the combustion chamber

into mechanical energies generating a mechanical force which pushes the lobes generatin

rotary torque.

Exhaust:Because of the pressing of a lobe against the stator, all the exhaust is se

through exhaust ports.

LIMITATIONS OF PISTON ENGINE COMPARED TO QUASI-TURBINE

1. The 4 stroke piston makes positive torque only 17% of the time and drag 83% of the time.

2. The duration of the piston rest time at top and bottom are unnecessarily too long which increases

the heat transfer to the engine block, thus reducing engine efficiency.

3. Some times during the negative valve overlap some fresh charge may escape with exhaust gases.

4. The need for a complex set of valves and camshaft uses substantial power.

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5. The valves inertia is a serious limitation to the engine revolution.

Quasi-turbine

IMPROVEMENTS OF QUASI-TURBINE OVER WANKLE ENGINE

The Wankel engine shaft turns at

The Quasi-turbine rotor and main shaft turns at the same speed.

The Wankel engine has a dead times. A complete rotor (not shaft) revolution is composed of three

relaxation strokes of 90 degrees each, separated by a 30 degre

The Quasi-turbine strokes are consecutive, with no dead time, allowing continuous combustion by

flame transfer.

The Wankel needs 2 sparkplugs because of the gas rolling effect and the

combustion chamber

shape. One sparkplug is sufficient in Quasi-turbine.

The Wankel engine is a "rotating piston engine" that is subject to a constan

vibration. The Quasi-turbine has a fixed center of gravity during rotation, and is a true zero

vibration engine

(like the turbine)

Due to its geometry, the Wankel exhaust and intake ports overlap extensively,

much before the expansion stroke is over, and closing much after the intake st

begun. The Quasi-turbine does not impose such a wide overlap detriment to efficiency.

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Quasi-turbine

QUASI TURBINE APPLICATIONS

PNEUMATIC QUASITUBINE

Quasi-turbine can be effectively used as a

engine. Pneumatic systems have a big advantage: they are cheap a

impractically expensive battery maintenance. If we send compressed air into the QT it can generate

driving torque effectively. If we send compressed air into the reciprocating engine it can work but it

has several problems with the inertia of flywheel, crank shaft, valves and cams. But QT has no

such problems. Tests are being done on QT with Nitrogen, Hydrogen etc., It is also tested for

locomotives. A car using pneumatic QT is also found.

STEAM QUASI-TURBINE

At now steam engines are obsolete because of their inh

low efficiency and bulkiness. But the present QT can also be used to generate the torque with steam

with a theoretical efficiency of 50%. It is also proposed for locomotive engine

conventional steam turbines require very high pressure in order to generate the high flow speedpermitting the turbine to be

efficient. This is not the case with the QT which is very efficient at all pressures, all

load levels and all RPM, and can produce substantial power. The QT greatly reduce

station construction and operation cost, improves substantially the risk and safety level.

COMPRESSORS

The Quasi-turbine has 2 intakes and 2 exits related

distinct circuits. Each circuit can be used to compress gas. The Quasi-turbine is a

displacement compressor, and does not make use of aero- or h

consideration. Reciprocal compressor reverses the flow while they compress, which is a

inertia, turbulent and heat generation limitation for high rpm. Because the flow is

and nearly unidirectional, QT is much less sensitive to flow reversal, turbulence and heat generation,

which improves it efficiency.

PUMPS

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Quasi-turbine

In the pump mode, a Quasi-turbine 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 Quasi-turbine is a pos

displacement pump, and does not make use of aero- or hydro-dynamic flow consideration.

PRODUCTS OF QUASI TURBINE

Pneumatic Quasi-turbine

600 & 75 indicates

the combustion chamber

volume

QT600SC

QT75SC

Steam Quasi-turbine

QT50SC

Quasi turbine Chain Saw


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Quasi-turbine

Air Car : Uses QT 600 SC engine

ADVANTAGES

Because it does not have internal accessories to drive, like the piston cam shaft and valve

train, additional energy is available to the end users.

Because the Quasi-turbine can be of large size, it is an efficient alternative to

for efficient energy conversion (steam) in electricity or from co-generation.

Because the Quasi-turbine (AC model with carriages) has the potential to r

detonation mode, it will not have the low power penalty of the Otto cycle,

provide a 50% energy saving in transportation application (much superior to hybr

concepts).

Fly wheel, eccentric are not required unlike Wankel engine.

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Quasi-turbine

Atmospheric gas pollution - Having a reduced combustion confinement time, the NOx are are

produced in lower

concentration.

Noise pollution - Having

4 combustions per

rotation, and due to a

longer gas relaxation

chamber, noise is reduced

by a factor of 20 or more!

The Quasi-turbine is a

vibration free engine

Oil free engine -

Lubrication is source of

pollution. The Quasi

- turbine has potential to

be an oil free engine.

DISADVANTAGES

Photo-detonation is not compatible with gaseous fuels like Hydrogen, C NG etc,

Sealing of the combustion chambers is difficult.

Construction of Quasi turbine is a job with difficulty.

CONCLUSIONS

Quasi-turbine is a rotary internal combustion engine having four chambers whose

shape varies according to the movement of the internal parts

QT has two varieties QT-AC (with carriages), QT-SC (with out carriages)

The combustion process is Photo Detonation which is a consequence of detonation

There is no necessity for anti-detonation agents and lubricants

The inertia of crank shaft, valves, cams etc., is avoided because direct rotary

is generated

Quasi-turbine is multi-fuel compatible (gasoline, diesel, H2, CNG etc.,)

All the disadvantages of Wankel rotary engine are eliminated

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Quasi-turbine

It has a wide range of applications such as Pneumatic Quasi-turbine, Steam Quasi-

turbine, compressors, pumps etc.,

It can generate higher torque even at low RPMs

REFERENCES

[1] http://web.mit.edu/newsoffice/tt/2003/mar05/hydrogen.html

[2] Scientific American of June 2002A Low-Pollution Engine Solution - New

sparkless- ignition automotive engines gear up to meet the challenge of cleaner combustion

[3] http://www.llnl.gov/str/Westbrook.html

[4] http://www.vok.lth.se/CE/research/HCCI/i_HCCI_uk.html

[5] www.qausiturbine.com

Document By

SANTOSH BHARADWAJ REDDY

Email: [email protected]

Engineeringpapers.blogspot.comMore Papers and Presentations available on above site
mailto:[email protected]:[email protected]


17/17

quasi-turbine combustion engine

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