Investigation of Flow Field and Fuel Spray in a Direct. Injection Diesel Engine via KIVA-II Program

The k - ε turbulent model in conjunction with a discrete fuel droplet model is used to evaluate the flow velocity field and fuel spray relationship in bowl combustion chambers of a directly injected diesel engine. Effects of flow field and fuel mixing are greatly influenced by the engine chamber geometry, the clearance volume and the engine speed. Fuel spray penetration and dispersion are primarily controlled by the injector hole size and fuel exit velocity, and that only at the tip of fuel spray near the end of injection, the structure of the spray is found to be most influential by the in-cylinder flow velocities. Computations were carried out through the newly published KIVA-II program.