Welcome To

Project seminar On

SIX STROKE IC ENGINE

Prepared by : Trambadiya vaibhav r.(1216BEME30059)

: Vachhani yagnik k. (1216BEME 30061)

Abstract

Modern world thrives on heat energy used in different forms.

Automobile industries is ever-growing industry.

95% of the automobile run on IC engines which are powered by fossil fuels.

Aim of thermal is to convert the heat energy to mechanical energy.

Efficiency of automobile is 30%

In a six stroke engine there are six strokes and out of these there are two power strokes.

The automotive industry may soon be revolutionized by a new six stroke design which adds a second power stroke, resulting in much more efficiency with less amount of pollution.

Introduction

The term six stroke engine describes two different approaches in the

internal combustion engine, developed since the 1990s, to improve its

efficiency and reduce emissions.

A six stroke engine derived its name from the fact that it is a mixture of two

and four stroke engine.

Two technical modifications in 4-stroke to 6-stroke.

Six stroke engines captures the wasted heat from the 4-stroke Otto cycle ,

creates steam and cools engine by providing free power stroke.

Working principal

A six stroke engine describes a number of different approaches in the

internal combustion engine to capture the waste heat from the four stroke

Otto cycle and use it to power an additional power and exhaust stroke of the

piston.

Designs either use steam or air as the working fluid for the additional

power stroke.

As well as extracting power, the additional stroke cools the engine and

removes the need for a cooling system making the engine lighter and giving

40% increased efficiency over the Otto Cycle.

Working

1st stroke (suction stroke) : During the first stroke the inlet valve opens and

air-fuel mixture from carburetor is sucked into the cylinder through the inlet

valve and piston moves from TDC to BDC.

2nd stroke (compression 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.

3rd stroke (1st power 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.

4th stroke (exhaust stroke) : During the fourth stroke, the exhaust valve opens

to remove the burned gases from the engine cylinder. Piston moves from BDC

to TDC

5th stroke (2nd power stroke) : During the fifth stroke, the exhaust valve

remains close and the air inlet valve open. Fresh air from the air inlet valve

enters the cylinder through the secondary air induction system. Piston moves

from TDC to BDC. In a six-stroke engine, when the combustion chamber

temperature reaches approx. 400 °F (200 °C). Just before the fifth stroke,

fresh water is injected directly into the hot combustion chamber through the

engine's fuel injector pump, which 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 Power stroke.

6th stroke (2nd exhaust stroke) : During the sixth stroke, the air exhaust

valve remains open. The air sucked into the cylinder during the fifth stroke is

removed to the atmosphere through the air exhaust valve. Piston moves from

BDC to TDC and six stroke cycle is completed.

Application

The industry trend away from cheaper two-stroke power in favor of

costlier but cleaner four-stroke engines in both Europe, Japan and South

East Asia makes a concept like the Beare six-stroke, which offers the best

of both worlds, project a strong case towards volume manufacture.

150cc six-stroke Taiwanese single-cylinder bike from Yingang is ready to

roll.

Types of six stroke ic engine

A. Single piston designs

A.1 Griffin six-stroke engine

A.2 Bajulaz six-stroke engine

A.3 Velozeta six-stroke engine

A.4 NIYKADO Six Stroke Engine

A.5 Crower six-stroke engine

B. Opposed piston designs

B.1 Beare Head

B.2 M4+2

B.3 Piston charger engine

Modified part

To make six-stroke engine from conventional four-stroke engine, a few

modifications must be done to specific parts on the conventional engine to

be sure that the new engine with six-stroke will run successfully.

A Mitsubishi single cylinder spark ignition engine was used to apply these

modifications on it.

These modifications are :1.Crankshaft to Camshaft Ratio Modification

2.Cam lobes

3.Valve timing diagram

Crankshaft to Camshaft Ratio Modification

In the six stroke engine the crankshaft has 1080 degrees of rotation for 360

degree rotation of the camshaft per cycle.Hence their corresponding sprockets

are having teeth in the ratio 3:1.

In the original four stroke engine the teeth of the sprockets of the crankshaft

and the Camshaft was in 2:1 ratio.

The 34 teeth sprocket of the four stroke engine camshaft was replaced by a 42

teeth sprocket in the six stroke engine.The camshaft sprockets were also

replaced from 17 teeth to 14 teeth to convert the four stroke engine into six

stroke engine.

Cam lobes

In the six stroke engine the 360 degrees of the cam has been divided into 60

degrees among the six strokes.

The valve provided at the exhaust has to be kept open during the fourth, fifth

and the sixth stroke.The cam has been made double lobed in order to avoid the

hitting of the exhaust valve with the piston head.

The profiles of the exhaust and the inlet cams have been shown in the figure

Valve timing diagram

The valve timing of the four stroke Honda engine has been changed.

The inlet valve opening (IVO) is 0° at TDC, same as that of the four

stroke Honda activa engine.

Inlet valve closes (IVC) at 25° after BDC, same as that of the four stroke

engine. Exhaust valve opens (EVO) 0° at BDC, which in the original

engine was 25° before BDC.

Velozeta reduced this 25° advanced opening of exhaust valve to extract

maximum work per cycle.

Exhaust valve closes 10 degree before TDC in order to prevent the loss of

air fuel mixture through the exhaust valve.

Comparison Of Six Stroke Engine With Four Stroke Engine

4

Advantages

The weight and power loss of conventional cooling system parts can be eliminated.

There is 40% reduction in fuel consumption.

Extracts work from heat that is ordinarily lost through the cooling system of a conventional engine.

Reduces exhaust emissions per a given power range.

Steam stroke cools the engine internally hence the use of much higher compression ratios.

Dramatic reduction in pollution normally up to 65%.

Lower engine temperature so easy to maintain the optimum engine temp. level for better performance.

Higher overall efficiency

Limitations and Obstacles

Injecting relatively cold water into a hot metal piston can damage it over

time from thermal expansion and contraction.

Separate water tank would have significant weight and space penalties

A steam-free cool down reduces the temperature inside the combustion

chamber.

Cold climate anti-freezing measures would be needed in the water

reservoir.

betterment

To prevent damages due to the action of cold water, we can utilize the

exhaust gases for pre- heating of water.

We can use a condenser instead of a separate water tank which will reuse

the distilled water for a period of cycles.

To compensate the temperature drop inside the chamber we can further

increase the Compression ratio which increases the power output making it

suitable for higher power requirements.

Conclusions

The concept of Six Stroke Engine seems to be rather eco-friendly andlow fuel consuming which can fulfill the needs of near future.

A lot of experiments are being conducted in order to improve theefficiency and workability of the engine.

In a six stroke engine the energy absorption is less because of slower acceleration of reciprocating parts The piston speed of the upper piston is about a quarter of the main piston; therefore its service life should be at least twice that of the main piston.

In the Beare design, per single cylinder, the number of parts is 15 compared to a four stroke of approx 40 to 50 parts. Also, to reduce manufacturing costs the head and block can be machined in one piece.

Better fuel economy and cleaner burning longer service intervals and considerably reduced tooling costs when compared with a conventional four-stroke design.

references

http://www.researchpublish.com

http://www.wikipedia.org/wiki/six_stroke_engine/

International Journal of Engineering Research & Technology

http://www.seminarsonly.com

http://www.google/sixstroke ic engine/

Queries