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Fuel Induction Systems for S.I. Engines. P M V Subbarao Professor Mechanical Engineering Department. Hardware to Satisfy the Needs of Otto Cycle.…. Thermo-flow Model for Carburetor. 1. One dimensional Isentropic Flow Through A Venturi. Reversible Subsonic Flow Nozzle : Venturi. p throat.
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Fuel Induction Systems for S.I. Engines P M V Subbarao Professor Mechanical Engineering Department Hardware to Satisfy the Needs of Otto Cycle.…...
Reversible Subsonic Flow Nozzle : Venturi pthroat p1 = p2s > pthroat p1 p1 p2s p
Real Flow Through A Venturi pthroat p2a < p2s p1 p1 p2s p p2a
Actual Air Flow Through Venturi Where Fuel Flow Through Orifice
Need for Fuel Injection in SI Engine • One of the main factors to achieve near complete combustion and better engine performance is the generation of a homogenous mixture of air and fuel in the cylinder. • The most of fuel should evaporate in the ports and mix with the inlet air. • Formation a liquid fuel layers at the port and the cylinder walls should be minimized. • The better solution is injection of fuel even in in the inlet port of gasoline (SI) vehicles using MPFI system.
Artificial Induction of Fuel • The fuel-induction systems for current (high percentage) spark-ignition engines inject the fuel. • There are both mechanical and electronically controlled injection systems. • Helps in achieving better volumetric efficiency • More uniform fuel distribution • More rapid response to changes in loading conditions • More precise control of the equivalence ratio.
The Need for Multi Physics Processes Modeling in Port Injection Large-scale introduction of Port Fuel Injection (PFI) in the mid-1980s. Metered fuel is introduced into each engine intake runner individually with a low-pressure, port fuel injector, by means of a brief injection event during each engine cycle. Early dynamometer tests indicated that numerous engine performance and emission parameters were significantly influenced by both; the cone angle of the spray plume and its direction relative to the back face of the intake valve.
Anatomy of EFI Solenoid Magnet