Investigation of the effects of cavitation on near nozzle dynamics in multi-hole gasoline direct injection sprays

Alex Gander,Cyril Crua,Giovanni Tretola,Konstantina Vogiatzaki,Paul Mcginn

doi:10.2218/iclass.2021.6014

Abstract

Investigation of the effects of cavitation on near nozzle dynamics in multi-hole gasoline direct injection sprays

Highlights

The use of gasoline direct injection (GDI) in modern light and heavy-duty vehicles has increased significantly over the past decade
The average distribution shows liquid structures of lower density leaving the full radius of the counter-bore hole.This is evident in Figure 5, which occurs from the interaction of trapped nitrogen in the sac of the injector and the initial onset of cavitation inside the nozzle at the inlet
In this study, a novel three fluid Volume of Fluid (VoF) spray modelling methodology has been developed and used in order to model the internal nozzle flow coupled with the external GDI multihole spray systems (ECN Spray G)

Summary

Introduction

The use of gasoline direct injection (GDI) in modern light and heavy-duty vehicles has increased significantly over the past decade. GDI injectors can present phenomena such as flash boiling, cavitation and spray collapse that are significantly different to the better documented diesel sprays. Spray G is a suitable validation test case for models that represent the key physics in gasoline sprays It has the necessary geometrical complexity in order to allow for interacting spray jets dynamics to be explored and it is mildly cavitating which allows to examine phase change phenomena present in multi-hole injectors. We extend our study in order to include the effect of in nozzle phenomena taking place in multi-hole injectors employing a novel three-fluid (including air,liquid and vapour) solver within OpenFOAM. The focus in the presentation of the results is on the cavitation formation in a multi-hole non symmetric geometry. In the end the major conclusions will be presented along with some discussion of what the steps in future work will be

Methods

Results

Conclusion