Behavior of droplets in pulsating air flow through an intake manifold.

Abstract

A numerical calculation supplemented by experimental work was conducted of the behavior of fuel droplets subjected to pulsating air flow in the T-branched duct of a square cross section for a better understanding of fuel supply characteristics in an intake manifold of an automotive spark ignition engine. The Lagrangian approach was adopted to derive simultaneous equations of momentum, heat and mass transfer for computing the locations, temperatures and diameters of moving droplets as a function of spatial coordinates The results were expressed primarily in terms of the location at the impact deposition of droplets relevant to the formation of liquid film on the bottom wall of the duct. It was revealed that the calculated results agreed well with the empirical data. It was also suggested that the undesirable aspects of liquid film might possibly by relieved if small droplets with high volatility and low density are infused at optimum timing into a warm air flow with a short period of pulsation.