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Post Injection Process in Port Injection Systems. P M V Subbarao Professor Mechanical Engineering Department. Occurrence of an unwanted Process along with Vaporization…. Fuel Droplet Dynamics : Prediction of Arrival. Flow Simulation. Compute the air velocity distribution.
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Post Injection Process in Port Injection Systems P M V Subbarao Professor Mechanical Engineering Department Occurrence of an unwanted Process along with Vaporization….
Flow Simulation Compute the air velocity distribution. Use this data and distance between the injection nozzle and intake valve, the timing at which the fuel spray reaches the intake valve or manifold valve or any other surface before entering the cylinder is to be predicted.
Prediction of Droplet Paths • After the spray break up there is a drag force exerted on the droplets from the surrounding gases. • This drag tends to decrease the relative velocity between the drop and the gas flow. • From the Newton's Second Law, the equation is: Where dsmd is the droplet diameter, ugand usmdare the velocities of the gas flow and the liquid fuel droplet, respectively. And the drag coefficient CDis given as:
YAMAHA MOTOR TECHNICAL REVIEW Shoichi Kato, Takanori Hayashida, Minoru Iida AFR 14.5, Coolant Temp. 80℃ MEP 380 kPa,
Analysis Of Mixture And Wall Film Behavior The injection system configuration, injection timing and coolant temperature exert an influence on combustion stability and duration. Change of injection affects mixture formation in the intake port, wall film location and amount, size and amount of droplets, and finally mixture distribution in the combustion chamber.
Simplified Engineering fuel Evaporation model • In a simplified engineering model a representative diameter for the entire group is defined to compute evaporation rate. • Equivalent diameter of same number of uniformly sized droplets having same total surface area.
Droplet evaporation • The droplet evaporation rate is given by where d is the droplet diameter, DABthe gas diffusivity, Sh* the non-dimensional Sherwood number, and Bmthe mass transfer number. The mass transfer number BMis equal to:
Surface temperature of the Port under different heating powers.