31-03-2011, 03:03 PM
Presented by,
S.SIVA ARUMUGAVEL
K.NAGARAJ SARAVANAN
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water inject six stroke engine
ABSTRACT
One of the most difficult challenges in engine technology today is the urgent need to increase engine thermal efficiency.
In the first approach, the engine captures the heat lost from the four-stroke Otto cycle or Diesel cycle and uses it to power an additional power and exhaust stroke of the piston in the same cylinder.
The pistons in this type of six-stroke engine go up and down six times for each injection of fuel.
Fresh water is injected into the cylinder after the exhaust 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.
A cooling system also serves to maximize volumetric charge efficiency by reducing the temperature of the charge during intake.
This design also claims to reduce fuel consumption by 40%.
INTRODUCTION
A six stroke engine describes a number of different approaches in the internal combustion engine to capture the waste heat from the four stroke engine and use it to power an additional power and exhaust stroke of the piston.
In our paper we utilise the waste heat from the exhaust and inject the treated water at end of the fourth stroke.
The water will convert into steam it will give additional power stroke of the engine.
By this additional stroke we can reduce the temperature of the engine.
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.
The pistons in a six stroke engine go up and down six times for each injection of fuel.
DIFFERENT TYPES OF SIX-STROKE ENGINES
Griffin six stroke engine,
Bajulaz six stroke engine,
Velozeta six-stroke engine,
Charge pump engine,
Beare Head Engine,
Crower six stroke engine.
SIX STROKE ENGINE
This engine is more efficient and powerful than the existing four stroke engines.
The engine is also having the scope of using heavy fuels and bio-fuels.
The engine with varied thermodynamic cycle of operation has better thermodynamic efficiency, reduced fuel Consumption, reduced pollution.
Nearly 40% more fuel efficiency can be obtained
THE SIX STROKES
Intake Stroke
Compression Stroke
Power Stroke
Exhaust Stroke
Steam Stroke
Exhaust Stroke
FIRST STROKE
During the first stroke the inlet valve is opened and air or air-fuel mixture is sucked into the cylinder.
SECOND STROKE
During this stroke air or air fuel mixture compressed to the maximum pressure.
THIRD STROKE
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.
FOURTH STROKE
During this stroke exhaust valve will be opened and burned gases send out to the atmosphere through the heat recovery system for warm-up the water.
FIFTH STROKE
In this stroke, Water is injected into the hot cylinder through the steam valve. By absorbing the heat from cylinder wall, the steam expands causing the piston to move down.
SIXTH STROKE
The expanded steam escapes through the opened exhaust valve and hence the piston moves upward. These exhaust steams also send via heat recovery system for warm-up the water.
WORKING OF SIX STROKE ENGINE
VALVES USED IN ENGINES
Inlet Valve
Exhaust Valve
Water injector
Inlet Valve:
It opens to supplied fresh air or air-fuel into the cylinder.
Exhaust Valve:
It opens to remove the burned gases and steam from the cylinder.
Water injector:
It opens to inject the water into the cylinder with high pressure.
FUNCTIONS OF VALVES IN ENGINES
HEAT RECOVERY SYSTEM
The main objective of this paper is to utilise the heat from exhaust by a system called heat recovery system
This system utilise the waste heat from the burned fuel and exhaust steam
Water tank is placed inside the recovery tank
At same time the exhaust burned gas and steam are going through this tank continuously heat the water before injecting it to the cylinder
BLOCK DIAGRAM OF HEAT RECOVERY SYSTEM
MODIFICATION OF MATERIAL
Since minimum cooling surface is necessary for high efficiency engine operation
The heat of combustion chamfer should be retained and should not be rejected to a cooling system if possible
The piston, cylinder and cylinder head can either be coated with a thermally insulating material like zirconium or they can be comprised of a thermally insulating ceramic like silicon nitride.
SOME FACTS ABOUT SIX-STROKE ENGINE
The water enters only when the temperature inside the cylinder reaches above 250oC.
The water cannot enter the spark plug, because of high temp.
The cylinder will not get rusted because engine will run for 15-30 sec before it shuts down.
Distilled water in order to avoid corrosion.
The heat from the exhaust (both Steam and burnt gases) is reused to heat the water to produce steam.
The six-stroke engine does not require any basic modification to the existing engines. All technological experience and production methods remain unaltered.
It can be working under multi fuel.
ADVANTAGES
It is having high efficiency compared to 4-stroke or 2-stroke engine.
Improves a typical engine’s fuel consumption.
No cooling system required.
The weight and power loss of most conventional cooling system parts such as the fan, radiator and coolant pump can be eliminated.
High Mechanical efficiency.
Physical engine size reduction.
The higher percentage of power strokes may allow lower working speeds, with higher torque output at lower and broader rpm ranges.
Reduced exhaust emissions per a given power range, CO can reduce up to 65%
CONCLUSION
A good engine needs high efficiency, high performance characteristics, low emission standards.
It seems that the above mentioned solution meets all these specified standards.
This engine is reducing fuel consumption and pollution without affecting performances drastically.
It has Up to 40% reduction in fuel consumption and 60% to 90% in polluting emissions, depending on the type of fuel being used.