Fuel Induction Systems for S.I. Engines

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Fuel Induction Systems for S.I. Engines

• P M V Subbarao
• Professor
• Mechanical Engineering Department

Right and Metered amount of Fuel per cycle...
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The Role of Fuel Induction System S.I. Engine

• The tasks of the fuel induction systems are
• to introduce right amount of fuel _at_ specified
  schedule.
• This schedule must be in agreement with allowable
  Heat Release Rate and duration of combustion.
• to prepare a mixture that satisfies the
  requirement of the engine using ambient air and
  fuel.
• This preparation is to be carried out over entire
  engine operating regime.
• In principle, the optimum air-fuel ratio for an
  engine is that which give the required power
  output with the lowest fuel consumption.
• It should also ensure smooth and reliable
  operation.

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Types of Fuel Induction Systems SI Engines

• The fuel Induction systems used in SI engine are
  classified as
• Carburetors.
• Throttle body Fuel Injection Systems.
• Multi Point Fuel Injection Systems.
• Direct Gasoline Injection System

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Evolution of Fuel Inductions Systems SI Engines
First Generation
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Evolution of Fuel Inductions Systems SI Engines
Second Generation
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Evolution of Fuel Inductions Systems Third
Generation
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Evolution of Fuel Inductions Systems Next
Generation
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Carbureted S.I. Engines

• There are some very obscure auto makers,
  primarily in Africa and Russia, who still build
  cars with carburetors.
• These cars are typically designs that have been
  purchased from their original manufacturers and
  remade for a new market.
• To keep expenses down, these auto makers avoid
  computer controls and use mechanical components
  such as a carburetor on their cars to make them
  more easily repairable.
• Many motorcycles, are one of the last holdouts
  of the factory production carburetors today.

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Jul 31, 2006  New motorbike technology bids
goodbye to the carburettor

• On June 26, Hero Honda, for the first time in
  India, launched the fuel injection
  (FI) technology in two-wheelers under the brand
  name Glamour FI. 

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Air-Fuel Supply Systems Carbureted S.I. Engines
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Thermo-flow Model for Carburetor
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One dimensional Isentropic Flow Through A Venturi
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Reversible Subsonic Flow Nozzle Venturi
pthroat
p1 p2s gt pthroat
p1
p2s
p
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Real Flow Through A Venturi
pthroat
p2a lt p2s
p1
p2s
p
p2a
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Practical Carburetor Venturi
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Actual Air Flow Through Venturi
Where
Fuel Flow Through Orifice
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Carburetor Performance
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Carburetor Performance
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Carburetor Performance
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Control of Equivalence Ratio using Carburetor
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Modern Carburetor