The document discusses the six stroke engine as a more efficient alternative to the traditional four stroke engine. It begins with an introduction explaining the need to increase engine efficiency. It then outlines the objectives of reducing fuel consumption, pollution, and increasing work extraction. It proceeds to classify and describe different six stroke engine designs including single piston approaches like the Crower engine and double piston approaches like the Beare Head engine. Key aspects of the six stroke cycle and comparisons to four stroke are summarized. Advantages include increased efficiency while limitations include higher costs. The conclusion maintains that the six stroke engine shows potential as a more eco-friendly and fuel efficient design for the future.

1. SUBMITTED BY-
ROLL NO- 1305440061

2. CONTENTS:-
Introduction………………..
Objective……………….
Classification of six stroke engine……………….
Comparison of six stroke engine with four stroke engine………
P-V and Torque –angle diagram……………….
Advantages………………….
Limitations…………………
Conclusion……………….
References.

3. Introduction:-
One of the most difficult challenge in engine technology
today is the urgent need to increase engine thermal
efficiency.Higher efficiency means less fuel consumption &
lower atmospheric emissions per unit of work produced by
the engine.
The six stroke engine is a type of internal
combustion engine based on the four stroke engine,but with
additional complexity intended to make it more efficient
and reduce emissions.Additional complexity means adding
two more stroke in the four stroke CI or SI engine.

4. Objectives:-
There are the following objectives:
(i) Reduction in fuel consumption.
(ii) Reduction in pollution.
(iii) More extraction of work per cycle.
(iv) Higher thermal efficiency of cycle.

5. Classification:
 The six stroke engines catagorised in two catagories according to design of the
piston of the engine.
(a)First Approach(Single piston design):-In the first approach the engine captures
the heat lost from the four stroke Otto cycle or diesel cycle and uses it to
additional power and exhaust stroke of the piston in the same cylinder.In this
type either steam or air used as the working fluid for the additional power
stroke.Ex:
(i)Crower six stroke engine.
(ii)Dyer six stroke engine.
(iii)Bajulaz six stroke engine.
(iv)Velozeta six stroke engine.
(b)Second Approach(Double piston design):-It uses a second opposed piston in
each cylinder that moves at half the cyclical rate of the main piston,thus giving
six piston movements per cycle.Ex:
(i)Beare head six stroke engine.
(ii)M 4+2 six stroke engine.

6. Crower’s six stroke engine:
 In a six stroke engine developed in U.S. by Bruce Crowner,distilled
water is injected in to the cylinder after the fourth stroke, and is
quickly turned to superheated steam,which causes the water to
expand to 1600 times its volume and forces the piston down for an
additional stroke.

7. Working:-
(i)Suction stroke (1st Stroke):-During the first stroke the piston
move from TDC to BDC by which inlet valve open and air fuel
mixture from carburetor sucked in to the cylinder in case of SI or
fresh air in case of CI engine through the inlet manifold.
(ii)First compression stroke(2nd stroke):-During the second stroke
piston moves from BDC to TDC by which fuel air mixture
compressed in the cylinder both valves remain closed during this
stroke, the compressed fuel air mixture inginited by the spark
plug thus combustion occurs inside the cylinder.
(iii)Expansion stroke/First Power stroke(3rd stroke):-During this
stroke product of combustion applied pressure on the piston by
which piston moves from TDC to BDC both valves remains
closed during this stroke.

8. (iv)Second Compression stroke(4th stroke):-The fourth stroke is again a
compression stroke .The piston move from BDC to TDC where the
remaining exhaust gases are compressed whichis similar to second
stroke.
(v)Second Power stroke(5th stroke):-Just before the end of the
compression stroke distilled water is sprayed in the combustion
chamber with the help of water injector.Due to fine spray of water and
high temperature it immediately gets converted in to superheated
steam.The steam applied pressure on the piston and piston moves
from TDC to BDC.Thus thermal enegy of steam is now converted in to
mechanical energy.
(vi)Exhaust stroke (6th stroke):-During the six stroke exhaust valve open
and inlet valve closed ,the piston move from BDC to TDC the waste
gases and the steam are released.

9. Dyer’s six stroke engine:-
 It is similar to the Crowner’s six stroke engine.
Bajulaz six stroke engine:-
It is similar to regular combustion engine in design.
There are ,however modification to the cylinder head with
two supplementary fixed capacity chamber:-
(a)A combustion chamber.
(b)Air preheating chamber.

10. Working:-
(i)First stroke:-Intake of pure air in
cylinder (5),valve(1)is open.
(ii)Second stroke:-compression of pure
air in the heating chamber (7),valve (2)
is open.

11. (iii)Third stroke:-Power stroke
(work)-release the combustion gases
in the cylinder valve(3) is open.
(iv)Fourth stroke:-Exhaust the
combustion gases valve (4) is open.

12. (v)Fifth stroke:-Power stroke(work)-
release of pure gas in the cylinder.
(vi)Sixth stroke:-Recompression of
pure air in to the combustion chamber.

13. Velozeta six stroke engine:-
 In a Velozeta engine, four strokes are similar to the four stroke IC or SI
engine.
 Fresh air is injected in to the cylinder during the exhaust stroke,which
expand by heat and therefore forces the piston down for an additional
power stroke .
 The engine seems to show 40% reduction in fuel consumption.
 The engine can run on a variety of fuels,ranging from gasoline and diesel
fuel to LPG.
 It shows 65% reduction in CO pollution when compared with the four
stroke from which it was developed.

14. Beare Head six stroke engine:-
This design was developed by Malcom Beare of Australia.
The technology combines a four stroke engine bottom end
with an apposed piston in the cylinder head working at half
the cyclical rate of the bottom piston.Fuctionally the
second piston replaces the valve mechanism of a
conventional engine.
The top and bottom crankshaft are connected via a drive
chain or toothed belt.

15. M 4+2 six stroke engine:-
 The M4+2 engines have much in common with the Beare Head engines,
combining two opposed pistons in the same cylinder. One piston works at half
the cyclical rate of the other, but while the main function of the second piston
in a Beare Head engine is to replace the valve mechanism of a conventional four
stroke engine, the M4+2 takes the principle one step further. The double-piston
combustion engine's work is based on the cooperation of both modules. The
air load change takes place in the two-stroke section of the engine. The piston
of the four-stroke section is an air load exchange aiding system, working as a
system of valves. The cylinder is filled with air or with an air-fuel mixture. The
filling process takes place at overpressure by the slide inlet system. The exhaust
gases are removed as in the classical two-stroke engine, by exhaust windows in
the cylinder. The fuel is supplied into the cylinder by a fuel injection system.
Ignition is realized by two spark plugs. The effective power output of the
double-piston engine is transferred by two crankshafts. The characteristic
feature of this engine is an opportunity of continuous change of cubic capacity
and compression rate during engine work by changing the piston's location.
The mechanical and thermodynamical models were meant for double-piston
engines, which enable to draw up new theoretical thermodynamic cycle for
internal combustion double pistons engine.

17. Comparison of six stroke engine with four
stroke engine(P-V diagram for Otto cycle):-

18. P-V diagram for dual cycle:-

19. Torque-angle diagram for four
stroke engine:-

20. Torque-angle diagram for six stroke
engine:-

21. Advantages:-
 Due to an additional power stroke efficiency of the engine increased.
 Better scavenging and more extraction of work .
 Reduction in fuel consumption by at least 40%.
 No cooling system required like heat exchanger in case of Crower six stroke
engine.
 Reduction in pollutants like NOx, CO ,CO2,photochemical smog etc, up to
55%.
 Multiple fuel used like as Bajulaz six stroke engine.
 Increase in indicated thermal efficiency.
 Minimize necessity of heat exchanger e.g. radiator.
Limitations:-
 Engine size increase due to number of cylinder and additional components.
 Higher manufacturing cost of six stroke engine.

22. Conclusion:-
The concept of Six Stroke Engine seems to be rather eco-
friendly and low fuel consuming which can fulfill the needs
of near future.
A lot of experiments are being conducted in order to
improve the efficiency and workability of the engine.

23. References:
• Kiran P , “ A feasibility study on waste heat recovery in six stroke I.C. Engine,
International Journal on Mechanical Engineering and Robotics (IJMER),
Volume-1, Issue-1, 2013.
• Vijay Chauhan, "A Review of Research in Mechanical Engineering on Recovery of
Waste Heat in Internal Combustion", 2012
• James C. Conklin, James P. Szybist “ A highly efficient six stroke internal
combustion engine cycle with water injection for in-cylinder exhaust heat
recovry” Energy 35 (2010) 1658-1664 .
• IC. Engine by V Ganesan,TMH.
• www.google.com
• www.wikipedia.com
• www.quasiturbine.com/QTMarchettiSthSixStroke0509
• www.bajulazas.com
• www.velozeta.com
• www.sixstroke.com