MADE BY:-

ROBIN CHAUHAN

INTRODUCTIONTYPES OF SIX STROKE ENGINESAPPROACHES OF SIX STROKE ENGINEADVATAGESDISADVANTAGESCONCLUSION

• The six-stroke engine is a type of internal combustion engine based on the four-stroke engine.

• First developed in early 1990’s• More efficient & reduce emissions.

Approaches for six stroke engine design

First approach

There is two additional strokes by the main piston as

fifth and sixth stroke

Second approach

It uses a second opposed piston which moves at half

the cyclical rate of the main piston

SIX STROKE ENGINE

FIRST APPROACH

Griffin six stroke engine

Bajulaz six stroke engine

Crower six stroke engine

Velozeta six stroke engine

SECOND APPROACH

Beare head six stroke engine

Charge pump engine

The key principle of the "Griffin Simplex" was a heated exhaust-jacketed external vapouriser, into which the fuel was sprayed.

Modifications to the cylinder head, with two supplementary fixed capacity chambers: a combustion chamber and an air preheating chamber above each cylinder

Velozeta’s six-stroke engine

First four strokes are same as a

conventional four stroke engine

In the fifth stroke, air is sucked

in to the cylinder

In the sixth stroke, a mixture of

air and unburned gases leaves out.

Working of the velozeta’s engine

First stroke:- During the

first stroke the inlet valve

opens and air-fuel mixture

from carburetor is sucked

into the cylinder through

the inlet manifold

Second stroke:-

During the second stroke, piston moves from BDC to TDC,

both the inlet valve and exhaust valve are closed and the air-fuel

mixture is compressed.

Third stroke:-

During the third stroke, power is obtained from the engine

by igniting the compressed air- fuel mixture using a spark plug.

Both valves remain closed. Piston moves from TDC to BDC.

Fourth stroke:-

During the fourth stroke, the exhaust valve and the reed valve

opens to remove the burned gases from the engine cylinder. Piston

moves from BDC to TDC.

Fifth stroke:-

During the fifth stroke, the exhaust valve remains open and the

reed valve closes. Fresh air from the air filter enters the cylinder

through the secondary air induction line provided at the exhaust

manifold. The reed valve opens.

Sixth stroke:-

During the sixth stroke, the exhaust valve remains open. The

air sucked into the cylinder during the fifth stroke is removed to the

atmosphere through the exhaust manifold. The reed valve opens and

the reed valve closes.

Crower six-stroke engine

Water is injected into the cylinder after the exhaust stroke and is instantly turned to steam, which expands and forces the piston down for an additional power stroke.

The technology combines a four stroke engine bottom end with an opposed piston in the cylinder head working at half the cyclical rate of the bottom piston

WORKING PRINCIPLE OF BEARE HEAD SIS STROKE ENGINE

FUEL IGNITES WITH PISTON AT THE TOP DEAD CENTER.

ROTARY VALVE OPENS, ALLOWING EXHAUST TO ESCAPE

EXHAUST STROKE BEGINS WHEN THE PISTON IS AT BOTTOM DEAD CENTER

EXHAUST STROKE ENDS, INTAKE BEGINS. ROTARY VALVE CUTS EXHAUST .INTAKE OF CHARGE INTO CYLINDER DUE TO PRESSURE DIFFERENCE.

The intake stroke happens when the piston is on its downward path with the intake valve open. This action creates suction, drawing atomized fuel in this case gasoline mixed with air, into the combustion chamber.

TOP PISTON NEARLY CLOSES COMPLETE INLET PORT AND THE COMPRESSION BEGINS.

COMBUSTION CHAMBER COMPLETELY SEALED AND READY FOR THE COMBUSTION.

the power stroke begins at a critical moment, just as the air-fuel mixture is at its most compressed. a supercharged voltage is delivered to the spark plugs from the ignition coil, at that point it ignites the fuel mixture. the valves in the engine are still closed during this period. thus the explosion forces the piston down to turn the engine's crankshaft, delivering the power via the gearbox and clutch to the driving wheels.

The piston charger charges the main cylinder and simultaneously regulates the inlet and the outlet aperture leading to no loss of air and fuel in the exhaust.

In the main cylinder, combustion takes place every turn as in a two-stroke engine and lubrication as in afour-stroke engine.

Fuel injection can take place in the piston charger, in the gas transfer channel or in the combustion chamber.

It is also possible to charge two working cylinders with one piston charger.

ADVANTAGES

Reduction in fuel consumption by at least 40%

Two expansions(work/Power stroke) in six strokes

Dramatic reduction in pollution ( up to 65%)

Higher overall efficiency

Lower engine temperature & noise level

Due to more air intake, the cooling system is improved

Better scavenging and more extraction of work per cycle

Less inertia due to lightness of moving parts

DISADVANTAGES

Brake power & indicated power per cycle per cylinder is

comparatively lesser

Engine size increases due to many number of cylinders &

additional components

Higher manufacturing cost of six stroke engine

CONCLUSION

Drastically reducing fuel consumption (by 40%) and

pollution (by 60-90%) without radically affecting

performances

It enables lower engine temperature and therefore increases

in the overall efficiency.