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SPLIT ENGINE



1. Abstract.

2. Introduction.3. Scuderi split cycle engine.4. How it works?5. How does the air get from one cylinder to the other?

6. When and where is the fuel injected?7. P-V curves.



Abstract : The first four-stroke piston was developed in 1876.

This four-stroke piston arrangement is still the

primary design of engines built today. Todays engines operate at only 33% efficiency.this

means that only 1/3 of the energy in each gallon offuel is used-the rest is lost through friction and heat.

With over a billion engines currently inworldwide,even small gains in efficiency will haveimpacts on the economy,dependency on foreignoil,and the environment.



Introduction : Split engines appeared as early as 1914.

Split cycle engines separate the four strokes of

intake, compression power, and exhaust into twoseparate but paired cylinders.

The first cylinder is used for the intake andcompression. The compressed air is transferredthrough a connecting passage or tube from thecompression cylinder into the second cylinder wherecombustion and exhaust occur.



Many different split cycleconfiguration have since beendeveloped ;however, none havematched the efficiency orperformance of conventionalengines.

Problems with previous split cycle

engines :

Poor breathing or volumetricefficiency.

Low thermal efficiency.



Scuderi split cycle engine

1.This engine is proposed by late Carmelo scuderi (1925

-2002) who spent over 40 years inventing, developingand commercializing new technology.

2. The Scuderi split cycle engine technology changes theheart of the I.C engine.

3. By using fluid and thermodynamic techniques, thescuderi technology improves how an engine convertschemical energy to mechanical energy.



In a conventional otto cycle engine,each cylinder performs four strokesper cycle: intake, compression,power, and exhaust. This meansthat two revolutions of thecrankshaft are required for eachpower stroke. The Scuderi Engine

divides these four strokes betweentwo paired cylinders: one forintake/compression and another forpower/exhaust.



The base Scuderi Engine is a split-cycle designthat divides the four strokes of a conventionalcombustion cycle over two paired cylinders.

one intake/compression cylinder and onepower/exhaust cylinder.

By firing after top-dead center, it produceshighly efficient, cleaner combustion with onecylinder and compressed air in the other.

Besides the improvements in efficiency andemissions, studies show that the ScuderiEngine is capable of producing more torque

than conventional gasoline and diesel engines.

How it works :



How does the air get from one

cylinder to the other : There is a short passageway connecting the

cylinders.

A conventional cam-actuated valve admits airto the combustion chamber, but a pressureactivated disk type valve admits air into thepassageway from the compression chamber

and prevents it from leaking back onto theintake cylinder.



When and where is the fuel

injected: Fuel is injected directly into the cylinder just as the valve opens.

The highly compressed air whooshes inso quickly and atomizes the injectedfuel so thoroughly that the spark is fired

to ignite it 11 to 15 degrees after TDC,even when running lean mixtures forincreased efficiency.



The power stroke is positivework, or energy that theexpanding gases of

combustion perform on theengine to create mechanicalwork .

The net energy produced by

the engine (its efficiency) isthe energy generated duringthe power stroke less theamount of energy consumedby the compression stroke.



Why it is so exceptional?

The scuderi split-cycleengine solves both thebreathing and thermalefficiency problems.



Solving the thermal efficiency problem byfiring after top dead center (ATDC).

o Although considered badpractice in conventional enginedesign , firing ATDC in a split

cycle arrangement eliminates thelosses created by recompressingthe gas.

o The big issue was not how to

solve the thermal efficiencyproblems of the split cycleengine, but rather how to fire ATDC.



High pressure and massiveturbulence

In the Scuderi Engine, firing after top dead center isaccomplished by using a combination of highpressure air in the transfer passage and high

turbulence in the power cylinder.

This high pressure air entering the power cylindercreates massive turbulence. The turbulence isfurther enhanced by keeping the valves open as long

as possible during combustion . The result is very rapid atomization of the fuel/air

mixture creating a fast flame speed or combustionrate faster than any previously obtained



Advantages of scuderi splitcycle engine.

One of the biggest advantages of the ScuderiSplit-Cycle Technology is designflexibility. Many features that requireadditional equipment or are just too difficultto implement in a conventional engine designare easily accomplished with a Scuderi Split-Cycle configuration. For example,

supercharging can be added simply byincreasing the diameter of the compressioncylinder.



Piston friction can bereduced by offsetting the

compression and powercylinders.

A Miller cycle can beachieved simply by

increasing the length of thepower cylinder.



Disadvantages : Cool air never enters the power cylinder so heat

would quickly build up causing lubrication oils tobreak down and components to fail.

Water cooled cylinder walls would be required toresolve this.

The crossover valve would experience highaccelerations so valve train durability could be anissue.

This very well might limit the rpm of the engine. Auto-ignition and /or flame propagation could occurin the crossover passage.



Conclusion:

The scuderi split cycle engine is having thermalefficiency about 42.6%,which is far more better thenconventional engine.

It greatly reduces the wastage of fuel, which is mostimportant thing to countries like India ,which isdependent on foreign countries for petroleum fuels.It reduces the burden on the imports customs.

By using ATDC technique we can greatly reduce thelosses created by re-compressing the gas. So , byusing this scuderi split cycle engine, we can changethe world of IC engines.

split engine fgfg

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