Transient spray behaviour of an air-assisted liquid injector

This paper presents an experimental study of an air-assisted, direct fuel injector in a constant volume chamber. This injector is the principal component of a spray guided injection system manufactured by Orbital Australia, Pty. Ltd. Ensemble averaged, planar images of the laser induced fluorescence (LIF) and Mie scattering from the spray are obtained to measure the Sauter mean diameter (SMD) for varying injection and chamber pressures. Back-illuminated images are also obtained at the same conditions, and the penetration length and spray width are also determined. Non-dimensional parameters for both the SMD and the penetration rate are then proposed, and which achieve good collapse of the experimental results. This demonstrates the significant injection parameters that control the spray behaviour.