Fuel Spray Pattern Control by Using L-Step Nozzle Injector

Abstract

In order to reduce fuel consumption and emission of direct injection gasoline engine, high atomization performance and controlling spray pattern in a fuel injector is required. Atomization performance has been achieved by using a swirler from our previous study. This paper describes a method to control spray pattern which swirl-type injector generates. An L-Step nozzle (L-cut orifice nozzle) which has developed by our previous study generates horse-shoe pattern spray which has rich and lean concentration region in horizontal section view. Correspondence between fuel flow with swirl and nozzle shape has been investigated. The mechanism of horse-shoe pattern generation can be described by geometrical relation between spray pattern and arrangement of L-cut step-wall. According to the investigation, the rich region and lean region can independently be controlled by means of arranging step-wall position and height.