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A Seminar On MULTI-MODE 2/4-STROKE INTERNAL COMBUSTION ENGINE” By Mr. MOHAMMED HUSAIN ESMAIL MASALAWALA Under The Guidance Of Prof. C. P. SHINDE Submitted In Partial Fulfillment of the Requirement For Bachelor of Engineering (Mechanical) Degree of University of Pune Department of Mechanical Engineering 1
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a seminar report on multi-mode 2/4 stroke internal combustion engine

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Page 1: a seminar report on multi-mode 2/4 stroke internal combustion engine

A

Seminar

On

“MULTI-MODE 2/4-STROKE INTERNAL COMBUSTION ENGINE”

By

Mr. MOHAMMED HUSAIN ESMAIL MASALAWALA

Under The Guidance Of

Prof. C. P. SHINDE

Submitted In Partial Fulfillment of the Requirement For

Bachelor of Engineering (Mechanical) Degree

of

University of Pune

Department of Mechanical Engineering

Late G.N. Sapkal College of Engineering,

Anjaneri, Nashik-4222122013-2014

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Kalyani Charitable Trust’s

Late G. N. Sapkal College of EngineeringSapkal Knowledge Hub, Kalyani Hills, Anjaneri, Trimbakeshwar Road,

Nashik – 422 212, Maharashtra State, India

CERTIFICATE

This is to certify that Mr. MOHAMMED HUSAIN ESMAIL

MASALAWALA has successfully completed his Seminar on the topic

“MULTI-MODE 2/4-STROKE INTERNAL COMBUSTION

ENGINE”, under the able guidance of Prof. C. P. SHINDE towards the

partial fulfillment of Third Year of Mechanical Engineering as laid

down by University of Pune during academic year 2013-14.

Prof C.P, Shinde. Prof. T.Y. Badgujar

[Seminar Guide] [ H.O.D. Mechanical ]

Dr. Basavaraj S. Balapgol

[Examiner] Principal

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CONTENT

ACKNOWLEDGEMENT

ABSTRACT

INDEX

Sr. No.

Description Page No.

1 Introduction 61.11.21.3

Increase in demand of IC engineScarcity of FuelPollution

678

2 2.1

Areas Of InterestPower

99

3

2.22.3

3.13.23.3

EfficiencyEmissionsTypes Of EngineSuction Ignition EngineCompressed Ignition EngineHomogenous Compressed Charged Engine

10

11111112

4

3.4 3.5

Hybrid EngineBoosted EngineConcept Of Multi-mode

121213

5 Technological Requirements 186 Successive Results 187 Field Of Implementations 198 Conclusion 219 Bibliography 21

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FIGURE INDEX

FIGURE NO. TITLE PAGE NO.

1.1.1 Increasing demand 6

1.2.1 Scarcity of fuel 7

3.1 Working graph 1 133.2 Working graph 2 137.1 Diesel engine for combat tanks 197.2 I F V 19

7.3 Diesel engine for military trucks 20

7.4 Special purpose vehicles 20

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ACKNOWLEDGEMENT

I take this opportunity to express our deep sense of gratitude and respect

towards our guide MR. C. P. SHINDE, Department of Mechanical Engineering, Late G N

Sapkal College Of Engineering , NASHIK. I am very much indebted to his for the

generosity, expertise and guidance; I have received from him while collecting data on this

seminar and throughout our studies. Without his support and timely guidance, the

completion of my seminar would have seemed a farfetched dream. In this respect I find

ourselves lucky to have his as our guide. He has guided us not only with the subject

matter, but also taught us the proper style and technique of working and presentation. It is

a great pleasure for me to express my gratitude towards those who are involved in the

completion of my seminar report. I whole-heartedly thank to our HOD Mr. T. Y.

BADGUJAR for their guidance. I am also indebted to all Sr. Engineers and others who

gave me their valuable time and guidance. The various information and sources I used

during my report completion find place in my report.

I am also grateful to Senior Seminar Coordinators respected sir’s.

MOHAMMED HUSAIN ESMAIL MASALAWALA

III year, V Semister

Dept. Of Mechanical Engineering (L.G.N.S.COE, Nashik) Magnetic Refrigeration

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ABSTRACT

In a multi-mode, 2-stroke/4-stroke internal combustion engine operation, by

switching the engine stroke from 4-stroke operation to 2-stroke operation so that the

combustion frequency is doubled, doubling of the engine power is achieved even at the

same work output per cycle. In order to meet the demand of extremely high power, the

engine operates in 4-stroke boosted SI operation transitioned from 2-stroke HCCI

operation at pre-set level of power and crank speed requirements. By combining the

multi-stroke (2-stroke HCCI and 4-stroke HCCI) and multi-mode operation (2-stroke

HCCI and 4-stroke boosted SI operation), full load range and overall high efficiency with

minimal NOx emission are achieved.

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1. INTRODUCTION

1.1 INCREASE IN DEMAND OF INTERNAL COMBUSTION ENGINE

Severe traffic congestion and automobile-related health problems will continue to

build internationally unless the use of cars is curtailed, according to a study by the World-

watch Institute, a United Nations-sponsored group.

With nearly 400 million cars in use worldwide and many developing countries ag-

gressively developing ''auto cultures,'' pollution will continue to increase, the study warns,

and it questions the wisdom of heavy third-world investment in transportation systems

that will serve ''a small, privileged class with ample purchasing power.''

The study recommends that in industrial nations higher taxes be assessed on cars

that get low gas mileage and calls for all governments to ''discourage auto use where pos-

sible'' in favour of public transportation.

''Government policies favouring private car ownership by a tiny but affluent elite

are squandering scarce resources and distorting development priorities,'' said Michael

Renner, the study's author. ''In Haiti, for example, only one out of every 200 people owns

a car, yet fully one-third of the country's import budget is devoted to fuel and transport

equipment.'' Auto Industry Challenges Report

Fig. 1.1.1 increasing demand

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1.2 SCARCITY OF FUEL

Due to tremendous increase in usage of automobiles the depletion rate of fossil

fuels is increasing . It has been estimated by USA council of Research in Fuel and Energy

Production that if the consumption of fuel would continue the fuel deposits would get

over within 50 years so it is utter most important to conserve our source of energy. The

graph below shows us a rough idea about the increase in the consumption of fuels usage.

After the year 1965 the fuel use increased and in year 1995 it increased nearly 3000

times. Therefore it is very important to check on the usage of fuels consumption the

government needs to take the required measurements in order to make a safe future.

Fig. 1.2.1

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1.3 POLLUTION

Cars and trucks produce air pollution throughout their life, including pollution

emitted during vehicle operation, re-fuelling, manufacturing, and disposal. Additional

emissions are associated with the refining and distribution of vehicle fuel.

Air pollution from cars and trucks is split into primary and secondary pollution.

Primary pollution is emitted directly into the atmosphere; secondary pollution results

from chemical reactions between pollutants in the atmosphere. The following are the

major pollutants from motor vehicles:

Particulate matter (PM).

Hydrocarbons (HC)

Nitrogen oxides (NOx).

Carbon monoxide (CO).

Carbon dioxide (CO2)

Sulphur dioxide (SO2).

Hazardous air pollutants (toxics)

Greenhouse gases

These gases are trapped in the converters situated at exhaust pipe of all the

vehicles. But all the gases don’t get trapped so it is important to design a engine which is

able to give same output power but should have less emissions.

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2 AREAS OF INTEREST

2.1 POWER

Firstly automobiles were used only for transportation purpose but now a days all

the youth is interested in buying a vehicle which has more power and is capable of getting

high accelerations and attain maximum speed in less time. So in order to fulfil

consumer’s demand the engine of the automobile should have high output power and

should be able to reach the expectations of the drivers.

Apart from this the there is requirement of power in I c engine in the defence

vehicles too. As they need to survive in different conditions and have to cover uneven

roads. So overall power of the automobile engine has to be increased.

2.2 EFFICIENCY

As we have seen in the previous chapter that the demand of I c engines are

increasing and because of which the total usage of fuel is also increased. This petroleum

isn’t a renewable source of energy, hence it needs to be conserved for the future

generations.

But according to current rate of usage of the fuel and the fuel deposits available

in earths crush it is estimated that in near future (approximately in next 20 years) the

fossil fuel deposits will be finished. So in order to preserve them we need to either

decrease the use of vehicles or we need to increase the average or efficiency of the I c

engine.

Usage of vehicle can’t be controlled so the only option left with humankind is to

increase the efficiency of the automobiles as much as possible.

2.3 EMMISIONS

The major source of air pollution is automobiles. In was seen that the 60% of air

pollutions is caused because of the automobiles. The emissions from the automobiles are

as follows-

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Particulate matter (PM). These particles of soot and metals give smog its murky colour. Fine particles — less than one-tenth the diameter of a hu-man hair — pose the most serious threat to human health, as they can penetrate deep into lungs. PM is a direct (primary) pollution and a secondary pollution from hydrocarbons, nitrogen oxides, and sulphur dioxides. Diesel exhaust is a major contributor to PM pollution.

Hydrocarbons (HC). These pollutants react with nitrogen oxides in the presence of sunlight to form ground level ozone, a primary ingredient in smog. Though beneficial in the upper atmosphere, at the ground level this gas irritates the respiratory system, causing coughing, choking, and reduced lung capacity.

Nitrogen oxides (NOx). These pollutants cause lung irritation and weaken the body's defences against respiratory infections such as pneumonia and influenza. In addition, they assist in the formation of ground level ozone and par-ticulate matter.

Carbon monoxide (CO). This odourless, colourless, and poisonous gas is formed by the combustion of fossil fuels such as gasoline and is emitted pri-marily from cars and trucks. When inhaled, CO blocks oxygen from the brain, heart, and other vital organs.

Sulfur dioxide (SO2). Power plants and motor vehicles create this pollutant by burning sulfur-containing fuels, especially diesel. Sulfur dioxide can react in the atmosphere to form fine particles and poses the largest health risk to young children and asthmatics.

Hazardous air pollutants (toxics). These chemical compounds have been linked to birth defects, cancer, and other serious illnesses. The Environmen-tal Protection Agency estimates that the air toxics emitted from cars and trucks — which include Benzene, acetaldehyde, and 1,3-butadiene — account for half of all cancers caused by air pollution.

Greenhouse gases. Motor vehicles also emit pollutants, such as car-bon dioxide, that contribute to global climate change. In fact, cars and trucks ac-count for over one-fifth of the United States' total global warming pollution.

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3 TYPES OF ENGINE

3.1 SUCTION IGNITION ENGINE

A petrol engine (known as a gasoline engine in North America) is an internal

combustion engine with spark-ignition, designed to run on petrol (gasoline) and similar

volatile fuels. It was invented in 1876 in Germany by German inventor Nicolaus August

Otto. In most petrol engines, the fuel and air are usually pre-mixed before compression

(although some modern petrol engines now use cylinder-direct petrol injection). The pre-

mixing was formerly done in a carburetor, but now it is done by electronically controlled

fuel injection, except in small engines where the cost/complication of electronics does not

justify the added engine efficiency. The method of mixing the fuel and air, and in using

spark plugs to initiate the combustion process

3.2 COMPRESSED IGNITION ENGINE

A diesel engine (also known as a compression-ignition engine) is an internal

combustion engine that uses the heat of compression to initiate ignition and burn the fuel

that has been injected into the combustion chamber. The engine was developed by

German inventor Rudolf Diesel in 1893. The diesel engine has the highest thermal

efficiency of any standard internal or external combustion engine due to its very high

compression ratio. Low-speed diesel engines (as used in ships and other applications

where overall engine weight is relatively unimportant) can have a thermal efficiency that

exceeds 50%

3.3 HOMOGENUOS COMPRESSED CHARGED ENGINE

HCCI has characteristics of the two most popular forms of combustion used in

SI (spark ignition) engines- homogeneous charge spark ignition (gasoline engines) and CI

engines: stratified charge compression ignition (diesel engines). As in homogeneous

charge spark ignition, the fuel and oxidizer are mixed together. However, rather than

using an electric discharge to ignite a portion of the mixture, the density and temperature

of the mixture are raised by compression until the entire mixture reacts spontaneously

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3.4 HYBRID ENGINE

Recently, Homogeneous Charge Compression Ignition (HCCI) engines have

been introduced, Which have higher efficiency comparable to CI engines as Well as min-

imum

particulate and NOx emissions characteristics, with the versatility of using gasoline as

well as diesel fuel. In HCCI engines, a spark plug or a high-pressure injector is

not used for initiation of the ignition of the fuel; instead, auto-ignition of the fuel (either

gasoline or diesel) and air mixture at the end of the compression stroke is achieved by

providing an elevated starting temperature at the beginning of the stroke.

This elevated temperature is achieved mostly by two Ways: heating the intake

air or using the exhaust gas from the previous cycle. In the latter system, one can re-in-

duct or trap the hot exhaust gas from the previous cycle by changing the valve timings.

The amount of the exhaust gas trapped in HCCI engines is usually about 50% in mass of

the total gas inside the cylinder. Although this exhaust gas increases the mixture temper-

ature before combustion, it actually decreases the peak temperature after combustion due

to dilution effect.

As a result, the NOx emission, which is exponentially proportional to the gas

temperature, is about two orders of magnitude lower than that in

conventional SI or CI engines. One can also achieve higher efficiency comparable to CI

engines due to the de-throttling of the intake manifold and combustion shape closer to

ideal Otto cycle.

3.5 BOOSTED ENGINE

To overcome the load limitation, current state of art utilizes a hybrid of HCCI/

SI or boosted HCCI. In a hybrid approach, a mode switching from SI to HCCI occurs

when the low load is required Where SI has poor efficiency. However, in this case, the

emission and efficiency benefits of HCCI operation are lost in the medium to high load

range, and the transient combustion control of HCCI in mode switching is not a subtle is-

sue in current research and industries. Secondly, boosted HCCI may give higher power,

but it is also limited since the combustion becomes too noisy and destructive due to the

high rate of pressure rise from rapid burn rate.

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4 CONCEPT OF MULTI-MODE

Fig. 3.1 working graph 1

Fig. 3.2 working graph 2

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In the above Fig. 3.1 and 3.2 show the comparison of engine operation strategy

between mode switching and mode/ stroke switching in terms of output power versus

engine speed. Fig. 3.1represents the conventional 4S SI/HCCI multi-mode strategy. At

low power output, the conventional SI engine suffers lower efficiency mainly due to the

intake throttling. Typical HCCI engine uses Wide-open-throttle and controls the output

power by varying the ratio between exhaust gas and fresh charge, called residual fraction

(RF). This de-throttling combined With nearly constant volume combustion process

results in higher efficiency of HCCI operation at low power.

In addition to the efficiency benefit, HCCI engine minimizes the NO,C

emissions from the dilution effect as mentioned above. For these reasons, the multi-mode

engine is operated in 4S HCCI at low power output region. On the other hand, at high

power limit, the RF in HCCI operation should be decreased to provide enough fresh

charge, which results in high rate of heat release and high peak pressure and temperature

due to lower dilution of exhaust gas, Which is very destructive to the engine.

Therefore, the mode switching from 4S HCCI to 4S SI occurs to meet the power

requirement as the power demand increases. At high power output, SI operation recovers

the efficiency by lowering the level of throttling, but the efficiency and emission benefits

of HCCI over SI are still sacrificed. At high engine speed, the 4S HCCI operation is

limited due to increased trapped gas temperature and hence suffers rapid heat release

during combustion. This sets the higher engine speed limit of 4S HCCI and the engine is

operated in 4S SI, even at low power output. Consequently, the intake throttling

is inevitable and the multi-mode engine suffers the low efficiency in this region of

operation.

Also it is seen in Fig. 3.2 shows the operational strategy of the present invention

combining multi-mode and multi-stroke operation strategies. At low power output and

low-to medium engine speed, the engine is running in 4S HCCI for the same reasons as in

the conventional multi-mode. As the intermediate or high power is required, the engine is

switched to 2S HCCI instead of 4S SI. Operating in 2S HCCI has two advantages over

using 4S SI. First, While doubling the combustion frequency in 2S HCCI produces power

output comparable to 4S SI, the benefits of high efficiency and low NO,C emissions of

HCCI operation are retained.

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Second, the stroke switching is able to be achieved more smoothly than mode

switching. The temperature range of exhaust gas is similar in 4S HCCI and 2S HCCI, but

typical 4S SI has 200-300 degrees higher exhaust temperature. Considering that HCCI

phasing is sensitive to the temperature of trapped gas, the stroke switching achieves

smoother transient operation than the mode switching.

Additionally, 2S HCCI can cover the high engine speed range with moderate

rate of heat release. In 2S operation, the mixture does not have enough time to mix

completely due to shortened gas exchange process and compression stroke, and hence this

less homogeneous mixture results in slower heat release than in 4S HCCI and makes 2S

HCCI a feasible solution to operate at higher speed. In addition, for extremely high power

and engine speed requirements, the engine may be switched to 4S boosted SI operation so

that the higher limit of the output power can be extended over 2S HCCI operation.

This mode switching is also readily possible due to the flexible valve timing and

intake boost system. Consequently, in accordance With the present invention, the

efficiency and emission benefits of HCCI can be exploited in typical operating range of

the multi-mode strategy and 4S boosted SI operation expands the operating range to the

higher power and speed region.

Fig. 3.3 shows a block diagram of an example engine system in accordance with

the present invention. The enabling technologies for multi-mode/multi-stroke operation

include variable valve actuation such as an EHVS (or cam-phaser) EHVS controller,

hydraulic supply, direct injector and combinations of supercharger, compressor and

turbine. In addition, the electronic control unit (ECU) monitors the power demand and

engine speed, and determines the optimal combustion strategies among 4S HCCI, 2S

HCCI and 4S boosted SI according to the pre-set operational map.

The information of the engine speed and the piston location for stroke/mode

switching is transmitted from the incremental encoder 6 which is connected to the crank

shaft. The in cylinder pressure trace is measured by a pressure transducer or ion sensor 7

and monitored by ECU 5. From the pressure signal, ECU 5 locates the combustion

phasing of the current operating condition and performs the feedback control of

combustion timing by changing valve timing or fuel injection timing. The measurement

in lambda sensor 14 provides the minute information, and intake and coolant temperature

sensors, which are not shown in Fig 3.2, are used to provide a feedback signal to reject

disturbances from real environment operation.

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Fig 3.1 and 3.2 show the valve timing diagrams, i.e., exhaust and intake valve

timings, for different combustion strategies. In FIGS. 3a, 3b and 3c, SOI stands for start

of injection, BDC for bottom dead centre, and TDC for top dead centre. Combustion TDC

is explicitly labelled With TDC and combustion, while intake TDC is simply labelled

TDC. In each of FIGS. 3a, 3b and 30, two engine revolutions are shown, i.e., 720 crank

angle degree (CAD) operation.

Fig. 3.1 shows the valve timing for 4S HCCI. To trap some amount of exhaust

gas, the exhaust valve closes before TDC and intake valve opens after TDC. There is no

valve overlap, called negative valve overlap (NVO). As depicted with lateral arrows in

Fig. 3.2, exhaust valve closing timing (EVC) and intake valve opening timing (IVO) are

adjusted symmetrically to change RF in the next cycle: the earlier EVC, the higher RE.

The fuel is injected after IVO, but this can be flexibly changed to meet the power output

and combustion phasing requirements. At the end of compression stroke, the combustion

phasing occurs near TDC, as shown in red. The valve timings and injection strategies

shown in Fig. 3.1 represent one example embodiment of 4S HCCI.

Other embodiments with other valve strategies such as late intake valve closing,

and other injection strategies such as multiple injection strategies, are possible.

Fig 3.2 shows the valve timing for 2S HCCI operation. It should be noted that there is one

combustion event per revolution, which is double the frequency than in 4S operation. The

exhaust valve opens during expansion stroke and closes after BDC. The intake valve

opens after EVO and closes in the middle of compression stroke. Hence, there is valve

overlap in 2S HCCI operation, and it is when the scavenging takes place.

The amount of valve overlap is used to control the power output: at larger valve

overlap, the air flow increases due to higher scavenging and the power output Will be

increased. Complete scavenging does not need to occur since HCCI operation requires

significant amount of burnt gas remaining inside the cylinder, Which makes the system

simpler because the complete scavenging has always been an issue of 2S operation.

The intake boost system is required for efficient scavenging and delivery of the intake air

during compression stroke. IVC is optimized to minimize the need for intake boost

pressure and hence maximize the overall system efficiency at a given condition. For

example, early IVC results in poor charging efficiency and late IVC induces backflow of

the mixture gases into the intake manifold, which results in the uncertainty of mixture

composition in the next cycle. The fuel for 2S HCCI operation is directly injected into the

cylinder after EVC to eliminate the fuel escape into the exhaust port.

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The injection timing and duration should be optimized to ensure that optimal

combustion phasing occurs. It is also possible to optimize the efficiency, emissions and

power by controlling the other valve timings. Fig. 3.3 shows the valve timing for 4S

boosted SI. Although it has some similarities to the typical valve timing of 4S DISI

(direct injection spark ignition), including valve overlap during gas exchange, injection

during intake stroke, and spark ignition before TDC, the difference is in that the intake

has boost pressure Which increases the power output, and IVC, spark timing, and

injection timing should be adjusted to pre vent knocking from occurring with high boost

pressure and compression ratio than in the typical DISI engine. To switch the

stroke/mode according to the power and speed requirements, the valve timings mentioned

above, as Well as spark ignition, boost of intake air and injection timings are changed as

present configuration. This switching should occur at combustion top dead center (TDC)

because this allows the engine to be ready for different stroke/mode operation in the next

cycle. The details of operation in each mode are explained below.

In 4S HCCI operation, the exhaust gas is trapped during NVO and mixed With

fresh air and fuel. The trapped gas raises the initial mixture temperature, so the mixture

Will be ignited at the end of compression stroke. To vary the power output, the RF is

changed by adjusting the duration of NVO, and combustion phasing is controlled by

injection timing. The super and turbo chargers and spark ignition system are turned

off in this operation.

When the combustion mode is switched to 2S HCCI, the super and turbo

chargers are activated. This super and turbo charging combination is configured to

optimize the overall efficiency of the engine. For example, at a low engine speed where

there is not enough energy available in the exhaust, the super charger is mainly operating,

while, at a high speed, both the super and turbo chargers are activated to boost the intake

air. The exact balance of operation between the super and turbo chargers depends on the

engine operating condition. An intercooler may be incorporated to increase the efficiency

of the boosting system. The engine power output is controlled by the duration of valve

overlap, that is, the extent of the scavenging. Due to shortened gas exchange process, 2S

HCCI can be more susceptible to cyclic variations, which requires the feedback control

on the combustion event. The combustion control is achieved by two factors: IVC which

determines the effective compression ratio, and injection timing which affects the homo-

geneity of mixture.

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5 TECHNOLOGICAL REQUIREMENTS

In accordance With the present invention, the intrinsic load limitation of HCCI

is overcome by switching the engine stroke from 4-stroke S‖ to 2-stroke S‖ so that the

combustion frequency is doubled and hence, even at the same work output per cycle, the

engine can double the power Which is comparable to that in the conventional SI/CI

engines. Although this stroke switching of the present invention produces about the

similar power range as the mode switching from 4S HCCI to 4S SI does, the differences

are in the emission and efficiency. HCCI operation is inherently clean and efficient

combustion even in 2S operation. Additionally, the stroke switching between the same

combustion strategies is much simpler and smoother than the mode switching between the

different strategies. Consequently, the stroke switching is superior to mode switch to

operate in 2S HCCI mode, the followings are required,

The first is the flexible valve system such as Electro-Hydraulic Valve System

(EHVS) or cam-phaser to operate at different valve profiles for stroke switching between

25 to 4S HCCI. Secondly, a super charger or combination of turbo and super chargers to

boost the intake manifolds to enable fast gas exchange for 2S operation. It is noteworthy that

in 2S HCCI, the complete scavenging is not required because large portion of the exhaust gas

is used in the next cycle, which makes the system and control simpler than in a hybrid of

4S/2S SI Which has additional intake system for 2S operation.

6 SUCCESSIVE RESULTS

The engine with the proposed improvements is capable almost to double (1.7 –

2.0 time increase) its output power and hold it up for a short period of time (this short

period depends on a type of the engine) without overheating. This feature allows the

vehicle power-to-weight ratio to be doubled upon necessity in accordance with the

vehicle operation conditions.

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7 FIELD OF IMPLEMENTATION

1 Diesel engines for combat tanks

Fig. 7.1 Diesel engines for combat tanks

2 Diesel engines for infantry fighting vehicles (IFV)

Fig. 7.2 IFV

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3 Diesel engines for military heavy trucks

FIG. 7.3 Diesel engines for military heavy trucks

4 Diesel engines for special purpose vehicles (i.e. emergency vehicles, fire trucks, etc.)

FIG. 7.4 special purpose vehicle

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8 CONCLUSION

Several projects are developed for different clients. Among them one is the 4-2-

stroke Diesel engine prototype built for the very common tractor engine. Another engine

for special purpose machine is slightly modernized in such a way that the same engine

can produce about 12% more power while the original lay out, weight, dimensions, and

specific fuel consumption (per hour)are almost unchanged. But this project is capable of

giving all the positive sides ie. it increases the efficiency increases the power and also

reduces the emissions.

9 BIBLIOGRAPHY

Andre Kulzer, Ansgar Christ, Martin Rauscher, Christina Sauer, Gernot Wurfel

and Thomas Blank, "Thermodynamic analysis and benchmark of various

gasoline combustion concepts," SAE paper 2006-01-0231, 2006.

Caton, P. A., Simon, A. J., Gerdes, J.C., and Edwards, C.F. "Residual-Effected

Homogeneous Charge Compression Ignition at a Low Compression Ratio Using

Exhaust Reinduction," Int. J. Engne Res., vol. 4, No. 3, 2003.

G. Haraldsson and B. Johansson, "Operating Conditions Using Spark Assisted

HCCI Combustion During Combustion Mode Transfer to SI in a Multi-Cylinder

VCR-HCCI Engine," SAE paper 2005-01-0109, 2005.

J. A. Eng, "Characterization of Pressure Waves in HCCI Combustion," SAE

paper 2002-01-2859, 2002.

J. Yang, T. Culp, and T. Kenney, "Development of a Gasoline Engine System

Using HCCI Technology-The Concept and the Test Results," SAE paper 2002-

01-2832, 2002.

Kaahaaina, N., Simon, A., Caton, P., and Edwards C. "Use of Dynamic Valving

to Achieve Residual-Affected Combustion," SAE Transactions, Journal of

Engines, vol. 110, Section 3, pp. 508-519, 2001-01-0549.

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