SEMINA SEMINAR R REPORT REPORT
On
Six Stroke Engines Submitted in partial fulfillment of the requirement for the award of the degree of
Bach Bachel elor or of Te Techn chnol olog ogy y In
MECHANICAL ENGINEERING
Submitted by th
Mukesh Mukesh Kumar Kumar -12093 -1209369 69 (7 sem.)
DEPARTMENT OF MECHANICAL ENGINEERING
Seth Jai Parkash Mukand Lal Institute of Engg. & Technology, Radaur Radaur – 135133 135133 (Yamuna (Yamuna Nagar Nagar )
(Affiliated To Kurukshetra University, Kurukshetra, Haryana, India)
TABLE OF CONTENTS S.No.
Content
Page No.
I
Acknowledgement
1
II
Abstract
2
1.
In Introduction
3
2.
Crower six stroke engine
4
3.
2.1
Working principle
5
2.2
Valves used in crower’s engine
7
2.3
Heat recovery system
7
2.4
Block di diagram of heat recovery sys system
8
2.5
Some fa facts ab about cr crowe ower’s si six-st x-strroke en engine
8
2.6
Adva dvantage ages of crowe werr’s six six stroke engi ngine
9
Bajulaz six stroke engine
9
3 .1
Features of bajulaz six stroke engine
10
3 .2
Working of bajulaz’s six stroke engine
10
3 .3
Six stroke engine cycle diagram
18
3 .4
Main advantages of the six -stroke engine
19
4.
Conclusion
21
5.
References
22
LIST OF FIGURES S.No.
Figure Number
Page No.
1.
Fig 2.1
6
2.
Fig 2.2
7
3.
Fig 2.3
8
4.
Fig 3.1
10
5.
Fig 3.2
12
6.
Fig 3.3
13
7.
Fig 3.4
14
8.
Fig 3.5
15
9.
Fig 3.6
16
10.
Fig 3.7
17
11.
Fig 3.8
18
ACKNOWLEDGEMENT There is always a sense of gratitude which one express to other for the helpful and needy service. They render during all the phases of life, It is my pleasure to be indebted to various people who directly or indirectly contributed in the department for this work work and who influenced my thinking, behavior and acts during during the course of study I express my sincere gratitude to Er Sanjeev Kumar Garg, HOD Mechanical Engineering Department for providing me an opportunity to undergo this s eminar, I am thankful to Er Pardeep Sharma, for his support, cooperation and motivation provided to me during the working of this seminar for constant inspiration, presence and blessings, Lastly I would like to thank the almighty and my parents for their moral support and my friends with whom I shared my day to day experience and received lots of suggestions that improved my quality of work.
Mukesh Kumar
1
ABSTRACT One of the most most difficult difficult challenge challengess in engine technolo technology gy today is the the urgent need to increase increase engine engine therm thermal al effic efficienc iency. y. The researc research h work work for obtain obtaining ing an engine engine which which havi having ng the same same or more power with higher fuel efficiency efficiency than the existing ones has started started before many years. As a result of all these researches a new engine concept is formed, which is is a six stroke engine. Lot of research works are conducting on this topic nowadays nowadays and already six types of six stroke engines engines were were discov discovere ered d yet. yet. Of these these the the recent recent develop developed ed two six stroke stroke engine engines, s, i.e. i.e. Bruce Bruce crower crowerss and and Bajula Bajulazz Six Six Strok Strokee Engi Engines nes are undergo undergoing ing tremen tremendous dous resear research ch works works.. During During every cycle cycle in a typical four stroke stroke engine, engine, piston moves up and down twice twice in the chamber, chamber, resulting resulting in four four total total strokes and one of which which is the power stroke stroke that that provides provides the torque torque to move the vehicle. But But in a six stroke 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 six -stroke design which adds a second power stroke, resulting in much more efficiency with less amount of pollution.
2
1. INTR INTROD ODUC UCTI TION ON The term six stroke engine describes two different approaches in the internal combustion engines, developed since the 1990s, to improve its efficiency and reduce emissions. In the first approach, approach, the engine captures the waste heat from from the four stroke Otto cycle or Diesel cycle and and uses it to get an additional additional power power and exhaust exhaust stroke of the the piston in the the same cylinder. cylinder. Designs either use steam or air as the working fluid for the additional power stroke. As well as extracting extracting power, power, the additional additional stroke cools cools the engine and removes removes the need for a cooling cooling system making making the the engine lighter lighter and and giving 40% 40% increased increased efficiency efficiency over over the normal Otto or Diesel Cycle. The pistons in this six stroke engine engine go up and down six times times for each injection of fuel. These six stroke stroke engines have 2 power power strokes; strokes; one by fuel fuel and one by steam or air. air. The curren currently tly notable notable six stroke stroke engine engine design design in this this clas classs is the Crower Crower's 's six stroke stroke engine engines, s, invented by Bruce Crower of the U.S.A. The second second approach approach to the the six stroke stroke engine engine is the Bajulaz Bajulaz Six Stroke Stroke Engine, Engine, which which was was invented invented in 1989 1989 by the the Bajulaz Bajulaz S, A company, company, based in Geneva, Geneva, Switzerland Switzerland. The Bajulaz six stroke engine is similar to a regular combustion engine in design. There was however modifications to the cylinder head, with two supplementary fixed capacity chambers, a combustion combustion chamber chamber and an air preheating preheating chamber chamber above each cylinder. cylinder. The combustion combustion chamber receives a charge of heated air from the cylinder; the injection of fuel begins, at the same same time it it burns burns which which increas increases es the therma thermall effici efficiency ency compar compared ed to a burn in in the cylin cylinder der.. The high pressure achieved is then released into the cylinder to work the power or expansion stroke. Meanwhile a second chamber which blankets the combustion chamber has its air content heated to a high degree by heat passing through the cylinder wall. This heated and pressurized air is then used to power an additional stroke of the piston.
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2. CROWER CROWER SIX STROKE STROKE ENGINE ENGINE This engine is invented by Bruce crower of California California in USA in the year 2004. Bruce Crower is actually actually a race car mechanic mechanic with his own workshop. workshop. In his six-stroke six-stroke engine, engine, power is obtained obtained in the third and sixth strokes. First First four strokes of this engine are similar to a normal four stroke engine and power power is delivered delivered in the third third stroke. stroke. Just prior to the fifth fifth stroke, stroke, water is injected injected directly directly into the heated heated cylinder cylinder via the converted converted diesel engine's engine's fuel injector injector pump. pump. The injected water absorbs the heat produced in the cylinder and converts into superheated steam, which causes the water to expand to 1600 times its volume and forces the piston down for an additional stroke i.e. the second power stroke. The phase change from liquid to steam removes the excess heat of the engine. engine . As a substantial portion of engine heat now leaves the cylinder in the form form of steam, no cooling cooling system radiator radiator is required. required. Energy Energy that is dissipat dissipated ed in conventional arrangements by the radiation cooling system has been converted into additional power strokes. In Crower's prototype, the water for the steam cycle is consumed at a rate approximately equal to that of the fuel, but in production models, the steam will be recaptured in a condenser condenser for re-use. re-use. This design design also claims claims to reduce reduce fuel consumption consumption by 40%. 40%. Crower's six stroke engine has the following important features 1. No cool coolin ing g syste system m requ requir ired ed.. 2. Improv Improves es a typica typicall engine’ engine’ss fuel consu consumpt mption. ion. 3. Requires Requires a supply of distilled distilled water water to act act as the medium medium for the the second power power stroke. stroke. 4. This engine engine is more more efficient efficient and and powerful powerful than the the existing existing four stroke engines. engines. 5. The engin enginee is also also having having the scope scope of using using heavy heavy fuel fuelss and bio-fuel bio-fuels. s. 6.
The engine with varied thermodynamic cycle of operation has better thermodynamic efficiency, reduced fuel Consumption, reduced pollution.
7. Nearly Nearly 40% more more fuel fuel effic efficien iency cy can can be obtaine obtained. d.
4
2.1 2.1 WO WORK RKIN ING G PRI PRINC NCIP IPLE LE The six strokes strokes included included in the crower’s crower’s engine are 1. Intak ntakee st stroke oke 2. Comp Compre ress ssio ion n strok strokee 3. Fuel Fuel powe powerr stro stroke ke 4. Fuel Fuel exh exhau aust st str strok okee 5. Ste Steam power stroke 6. Stea Steam m exha exhaus ustt stro stroke ke
2.1. 2.1.1. 1. Inta Intake ke stro stroke ke
During the first first stroke the inlet valve is opened and air or air-fuel mixture is sucked into the cylinder. Thus the charge charge is inducted into the combustion chamber. This is done by the suction created due to the downward movement of the piston into the cylinder from top dead center to bottom dead center. 2.1. 2.1.2 2
Comp Compre ress ssio ion n strok strokee
During During this stroke stroke air or air fuel mixture mixture compressed compressed to the maximum maximum pressure. pressure. The piston moves from bottom dead center to top dead center, and the charge inside the cylinder gets compressed. 2.1. 2.1.3 3
Fuel Fuel powe powerr str strok okee
This is first power stroke of the engine. This is given by primary fuel (petrol or diesel or LPG). During this stroke all valves are remains closed. The charge gets ignited by some suitable suitable means, depending upon the type of fuel used. Due to the combustion the of the air fuel mixture, the combustion products expands and they exerts a pressure on the piston head, thereby moving the piston from top dead center to bottom dead center, and hence producing the first power stroke. 2.1. 2.1.4 4
Fuel Fuel exh exhau aust st str strok okee
During this stroke, the exhaust valve will be opened and and burned gases send out to the atmosphere through through the heat recovery recovery system system to warm-up warm-up the water. water. This is is done by the upward upward movemen movementt of the piston from bottom dead center to the top dead center. All of these four strokes are similar to the t he four strokes of an ordinary four stroke s troke engine. 5
2.1.5
Steam power wer stroke
This is the second power stroke of the Crower’s six stroke engine. In this stroke, water is injected into the hot hot cylinder cylinder through through the the steam valve. By By absorbing absorbing the heat heat from cylinder cylinder walls, walls, the water gets converted converted to a superheated steam and the steam expands causing the piston to move down, from top dead center to bottom dead d ead center by exerting a pressure on o n the piston head. 2.1. 2.1.6 6
Stea Steam m exha exhaus ustt stro stroke ke
The expanded steam escapes through through the opened exhaust valve by the upward movement of the piston into the cylinder. This exhaust steams is also sent via heat recovery system to warm-up the water.
Fig 2.1
6
2.2 VALVES VALVES USED USED IN CROWER CROWER’S ’S ENGINE ENGINE 1.
Inlet Inlet Valve Valve
2.
Exhaus Exhaustt Valve Valve
3.
Water Water injecto injectorr
2.2.1 2.2.1 Function Functionss of all the valves valves in in engine engine 1. Inlet let Valv Valvee
It opens to supplied fresh air or air-fuel air -fuel into the cylinder. 2. Exh Exhaust ust Valv Valvee
It opens to remove the burned gases and steam from the cylinder. 3. Wate Waterr inj injec ecto torr
It opens opens to inject the the water into into the cylinder with high pressure.
Fig 2.2
2.3 HEAT HEAT RECO RECOVE VERY RY SYST SYSTEM EM The main objective of is to utilize the heat from exhaust by a system called heat recovery system. This system system utilizes utilizes the waste heat from the burnt burnt fuel and exhaust exhaust steam. Water tank is placed inside inside the recove recovery ry tank. tank. At same same time time the exhaus exhaustt burnt burnt gases gases and the steam steam passes passes throug through h this this tank tank and thereby thereby contin continuous uously ly transfe transferri rring ng the heat to the water water before before inject injecting ing it to the cylin cylinder. der.
7
2.4 BLOCK BLOCK DIAGRA DIAGRAM M OF HEAT HEAT RECOVER RECOVERY Y SYSTEM SYSTEM
Fig 2.3
2.5 2.5 SO SOME ME FAC FACTS TS ABO ABOUT UT CROW CROWER ER’S ’S SIXSIX-ST STRO ROKE KE ENG ENGIN INE E 1. The water water enters enters only when the the tempera temperature ture inside the cylinde cylinderr reaches reaches above above 250 250 degree Celsius. 2. The water water cannot enter the spark spark plug, because of high high temp temp of the the spark spark plug. plug. 3. The cylinder cylinder will will not get get rusted rusted because engine will run for for 15-30 sec before before it it shuts shuts down, thereby removing all the water from the cylinder . 4. Dist Distil ille led d wate waterr may also also be used used in ord order er to to avoi avoid d the the corr corrosi osion on.. 5. The heat heat from from the the exhaust exhaust (both (both Steam Steam and burnt gases) is reused reused to heat the the water water before before injecting it to the cylinder. 6. The six-strok six-strokee engine engine does not require require any basic basic modifica modification tion to to the existi existing ng engines engines and all the technologic technological al experience experience and production production methods remain remain unaltered. unaltered. 7. It can can als also o be be work workin ing g usin using g mult multip iple le fuel fuels. s.
8
2.6 ADVANT ADVANTAG AGES ES OF CROWER CROWER’S ’S SIX STROK STROKE E ENG ENGINE INE 1. It is havi having ng a higher higher effi effici cien ency cy as comp compar ared ed to the the 4-st 4-stro roke ke and and 2-st 2-stro roke ke engin engines. es. 2. Improv Improves es a typical typical engine engine’s ’s fuel fuel consump consumptio tion. n. 3. No cooli cooling ng syste system m requir required ed in the the engine engine.. 4. The weight weight and power power loss of most conventi conventional onal cooling cooling system system parts parts such as the the fan, radiator radiator and coolant coolant pump can be eliminated eliminated.. 5. Higher Higher mechani mechanical cal effici efficiency ency is obtain obtained ed in the engine. engine. 6. Physical Physical engine engine size size reduced reduced due to removal removal of the cooling cooling system. system. 7. The higher higher percentage percentage of power strokes strokes may allow lower lower working working speeds, speeds, with with higher higher torque output at lower and broader rpm ranges. 8. Reduced Reduced exhaust emissions emissions per a given power range, range, CO CO can reduce reduce up to 65%.
3. BAJULA BAJULAZ Z SIX SIX STROK STROKE E ENGIN ENGINE E
The Bajula Bajulazz Six Stroke Stroke Engine Engine was inve invente nted d in 1989 1989 by the Baju Bajulaz laz S A Company Company based based in Geneva, Switzerland. The Bajulaz Bajulaz six stroke stroke engine engine is similar similar to a regular regular internal internal combustion combustion engine in design. design. There was however however modificati modifications ons to the cylinde cylinderr head, with with two supplementar supplementary y fixed capacity capacity chambers, chambers, a combustion chamber chamber and an air preheating chamber chamber above each cylinder. cylinder. The combustion combustion chamber chamber receives receives a charge of heated heated air from the cylinder cylinder;; the injection injection of of fuel fuel begins, at the the same time it burns burns which which increases increases the thermal thermal efficiency efficiency compared to a burn in the cylinder. The high pressure achieved is then released into th th e cylinder to work the power power or expansion expansion stroke. stroke. Meanwhile Meanwhile a second chamber chamber which blankets blankets the combustion combustion chamber chamber has its air content content heated to a high degree degree by heat heat passing passing through through the cylinder wall. This heated heated and pressurized air is then used to power an additional additional stroke of the piston. The advantages of the engine include reduction in fuel consumption by 40%, multi-fuel usage capability, and a dramatic reduction reduction in pollution.
9
3.1 FEATURES OF OF BAJULAZ SIX STROKE ENGINE Bajulaz six stroke engine has the following features 1. Reduct Reduction ion in in fuel fuel consump consumptio tion n by at leas leastt 40% 2. Two expansi expansions ons (wor (work) k) in in six six stroke strokess 3. Dramat Dramatic ic redu reducti ction on in in pollu pollutio tion n 4. Liqu Liquef efie ied d Petr Petrol oleu eum m Gas Gas 5. Costs comparab comparable le to those those of a four-stroke four-stroke engine engine combustion combustion engine engine in in design. design.
3.2 WORKING WORKING OF BAJULAZ’S BAJULAZ’S SIX STROKE STROKE ENGIN ENGINE E The engine has the following main components 1. Intak ntakee valv valvee 2. He Heat ating ing cham chamber ber valv valvee 3. Combus Combusti tion on cha chamb mber er val valve ve 4. Exha Exhaus ustt valv valvee 5. Cylinder 6. Comb Combus usti tion on cham chambe ber r 7. Air Air heat heatin ing g cham chambe ber r 8. Wall Wall of com combu bust stio ion n cham chambe ber r 9. Fuel Fuel injec njecttor 10. Heatin Heating g plug 11. 11. Pist Piston on 12. Cranks Crankshaf haftt
Fig 3.1
10
The sketch shows the cylinder head equipped with both chambers chambers and four valves of which two are conventional (intake and exhaust). The two others are made of heavy-duty heat-resisting material. During the combustion and the air heating processes, the valves could open under the pressure within the chambers. To avoid this, a piston is installed on both valve shafts, which compensate this pressure. Being a six-stroke cycle, the camshaft speed is one third of the crankshaft speed. The combustion chambers walls are glowing when the engine is running. Their small thickness allows heat exchange with the air-heating chamber, which is surrounding the combustion chamber. The air-heating chamber is isolated from the cylinder head to reduce thermal loss. (To make the engine presentation easier, the details of the chambers are not described on the cycle sketch). Through heat transfer from the combustion chamber to the heating chamber, the work is distributed over two strokes, which results in less pressure on the piston and greater smoothness of operation. In addition, since the combustion combustion chamber is isolated from the cylinder cylinder by its valves, the moving parts, especially the piston, are not subject to any excessive stress from the very high temperatures and pressures. They are also protected from explosive combustion or auto-ignition, which are observed on ignition of the air-fuel mixture in conventional gas or diesel engines. The combustion and air-heating chambers have different compression ratio. The compression ratio is high for the heating chamber, which operates on an external cycle and is supplied solely with pure air. On the other hand, the compression ratio is low for the combustion chamber, which operates on an internal combustion cycle. The combustion of all injected fuel is insured, first, by the supply of preheated pure air in the combustion chamber, then, by the glowing walls of the chamber, which act as multiple spark plugs. In order to facilitate cold starts, the combustion chamber is fitted with a heater he ater plug (glow plug). In contrast to a diesel engine, which requires a heavy construction, this multi-fuel engine, which can also use diesel fuel, may be built in a much lighter fashion than that of a gas engine, especially in the case of all moving parts.
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Injection and combustion takes place in the closed combustion chamber, therefore therefore at a constant volume, over 360 degrees of crankshaft angle. This feature gives plenty of time for the fuel to burn ideally, and releases every potential calorie (first contribution to pollution reduction). Bajulaz’s six stroke engine consists of the following six strokes 3.2.1 3.2.1 1st strok strokee (suctio (suction n stroke stroke))
The inlet valve (1) is kept open. Due to cranking, the piston moves downward downward which results in the formation of a pressure difference due to which pure air enters the cylinder (5). The crankshaft crankshaft completes completes revolution revolution for half half cycle. cycle.
Fig 3.2
12
3.2.2 3.2.2 2nd stroke stroke (compr (compressi ession on stroke) stroke)
The inlet valve closes and the heating chamber valve opens. The piston moves upwards due to cranking forcing the pure air into heating chamber. The air at this stage is converted to high high pressure.
Fig 3.3
13
3.2.3 3.2.3 3rd stroke stroke (1st (1st power power strok stroke) e)
The combustion chamber valve opens and the gases of combustion enter the cylinder. The high pressure combustion products enter into the cylinder, and exert a force on the piston head, forcing it to move downwards, thereby producing the first power stroke. This stroke gives the 180 degree revolution to the crankshaft.
Fig 3.4
14
3.2.4 3.2.4 4th strok strokee (exhaus (exhaustt stroke) stroke)
The exhaust valve opens. The piston moves upwards and the exhaust gases are removed via this valve. The crankshaft rotates another half cycle. At this stage the crankshaft completes 2 full cycles.
Fig 3.5
15
3.2.5 3.2.5 5th strok strokee (2nd power power strok stroke) e)
The heating chamber chamber valve opens and the pure air now at high high pressure and high temperature enters enters the cylinder cylinder as shown in the figure which does work on the piston piston and hence it moves downwards resulting in the 2nd power stroke. The crankshaft completes another another half cycle.
Fig 3.6
16
3.2. 3.2.6 6 6th 6th stro stroke ke
Finally the combustion chamber valve opens the piston moves upwards forcing the pure air into the combustion chamber. The crankshaft will complete 3 full full cycles at the end of the 6th stroke. stroke.
Fig 3.7
17
3.3 SIX STROKE STROKE ENGINE ENGINE CYCLE CYCLE DIAGRAM DIAGRAM
Fig 3.8
3.3.1 External combustion combustion cycle cycle (divided (divided in 4 events) events)
No direct contact between the air and the heating source. 1. e1. (Ev (Eveent 1) 1)
Pure air intake in the cylinder (dynamic event). 2. e2. (Ev (Eveent 2) 2)
Compression of pure air in the heating chamber (d ynamic event). 3. e3. (Ev (Eveent 3) 3)
Keeping pure air pressure in closed chamber where a maximum heat exchange occurs with the combustion chambers walls, without direct action on the crankshaft (static event).
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4. e4. (Ev (Eveent 4) 4)
Expansion of the superheated air in the cylinder work (dynamic event).
3.3.2 Internal Internal combustion combustion cycle cycle (divided (divided in 4 events) events)
Direct contact between the air and the heating source. 5. I1. I1. (Ev (Eveent 5)
Re-compression of pure heated air in the combustion chamber chamber (dynamic event). 6. I2. I2. (Ev (Eveent 6)
Fuel injection and combustion in closed combustion chamber, without direct action on the crankshaft (static event). 7. I3. I3. (Ev (Eveent 7)
Combustion gases expanding in the cylinder work (dynamic event). 8. I4. I4. (Ev (Eveent 8)
Combustion gases exhaust (dynamic event).
3.4 MAIN ADVANTAG ADVANTAGES ES OF THE SIX-STROK SIX-STROKE E ENGINE 3.4.1 3.4.1
Reducti Reduction on in in fuel fuel consumpt consumption ion by at at least least 40%
An operating operating efficiency efficiency of approximatel approximately y 50%, hence the large large reduction reduction in specific fuel consumption. The Operating efficiency efficiency of current petrol engine is of the order of 30%. The specific power of the six-stroke engine will not be less than that of a four-stroke petrol engine, the increase in thermal efficiency compensating for the issue due to the two additional strokes. strokes. 3.4.2 3.4.2
Two expa expans nsion ionss (wor (work) k) in in six six stro stroke kess
Since the work cycles occur on two strokes (3600 out of 10800 ) or 8% more than in a fourstroke engine (1800 out of 720 ), ), the torque is much more even. This lead to to very smooth operation at low speed without any significant effects effects on consumption and the emission of pollutants, the combustion not being affected by the engine speed. These advantages are very important in improving the performance of car in town traffic.
3.4.3 3.4.3
Drama Dramati ticc red reduct uctio ion n in in poll pollut ution ion
Chemical, noise and thermal pollution are reduced, on the one hand, in proportion to the reduction in specific consumption, and on the other, through the engine’s own characteristics 19
which will help to considerably lower lower HC, CO and NO emissions. Furthermore, its ability to run with fuels of vegetable origin and weakly pollutant gases under optimum conditions, gives it qualities which will allow it to match up to the strictest standards.
3.4.4
Multi fuel
Multi fuel for excellence, excellence, it can can use the the most varied varied fuels, fuels, of any origin origin (fossil (fossil or or vegetable vegetable), ), from diesel to L.P.G. or animal grease. The difference in inflammability or antiknock rating does not present any problem in combustion. It’s light, standard petrol engine construction, and the low compression ration of the combustion chamber; do not exclude the use of diesel fuel. Methanol-petrol mixture is also recommended. 3.4.5 3.4.5
Cost compara comparable ble to those those of a four-str four-stroke oke engine. engine.
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4. CON CONCLUS CLUSIO ION N There is, at this day, no wonder solution for the replacement of the internal combustion engine. Only improvements of the current technology can help it progress within reasonable time and financial limits. The six-stroke engine fits perfectly into this view. Its adoption by the automobile industry would have a tremendous impact on the environment and world economy, assuming up to 40% reduction in fuel consumption and 60% to 90% in polluting emissions, depending on the type of the fuel being being used. Drastically Drastically reducing reducing fuel fuel consumption consumption and pollution pollution without radically affecting performances would allow the current concept of the automobile to be reassessed. The six stroke engine engine modification promises dramatic dramatic reduction of pollution and fuel consumption of an internal combustion engine. The fuel efficiency of the engine can be increased and also the valve timing can be effectively arranged to extract more work per cycle. Better scavenging is possible as air intake occurs during the fifth fifth stroke and the exhaust during the sixth stroke. Due to more air intake, the cooling system is improved. It enables lower engine temperature and therefore increases in the overall efficiency. efficiency. Automobiles equipped with the sixstroke engine could appear in the market within 3 to 5 years.
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5. REFERENCE REFERENCES S
1. http://www http://www.autow .autoweek.com eek.com/apps/ /apps/pbcs.dl pbcs.dll/ar l/article ticle?AID= ?AID=/20060 /20060227/FR 227/FREE/3022 EE/302270007/ 70007/1023/T 1023/TH H ISWEEKSISSUE 2. http://www http://www.newin .newindpress dpress.com/N .com/NewsIt ewsItems.as ems.asp?ID=I p?ID=IEO20060 EO20060903112 903112344&Topi 344&Topic=0&T c=0&Title=Th itle=Th iruvananthapuram Page=O 3. http://www http://www.autoc .autocarind arindia.com ia.com/new/I /new/Inform nformation ation.asp?id= .asp?id=1263 1263 4. ww www. w.si sixs xstr trok oke. e.co com m 5. High speed internal internal combusti combustion on engines engines by John B. Heywood. Heywood.
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