3D Numerical Simulation of Stratified Mixture Formation of DI LPG Engine

Abstract:

Low-carbon economy is a necessary requirement for sustainable development. LPG Direct Injection (DI) method can greatly improve the engines power performance, fuel economy and emission characteristics, hence a new wall-guided combustion system with a specially designed piston cavity used to form lean stratified mixture for DI LPG engine was proposed. In this paper, the stratified mixture formation process of a DI LPG engine was simulated. Before this, the model and method used in the simulation was firstly validated by simulating mixture formation process in an optical engine with conventional piston. The simulation results of the stratified mixture formation showed that, the mixture could gradually move upward along the combustion chamber wall under the guide of the spray induced entrainment vortex and the wall. At the same time, the rich mixture would diffuse to its surroundings. Finally, by the time to ignition, the ignitable stratified lean mixture could be formed.

• Periodical: Applied Mechanics and Materials (Volume 328)
• Pages: 975-980
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.328.975
• Online since: June 2013
• Authors: Juan Xu, Zhong Hai Zhou, Zong Rui Hao, Bo Yan Xu
• Keywords: Liquid Phase LPG Injection, Numerical Simulation, Stratified Lean Mixture

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