Transcript
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.