Effect of Engine Variables on Combustion Performance of Lean Burn Spark Ignition Engine: An Overview

Abstract

In the development of internal combustion engines, there has been a continuous effort to reduce fuel consumption and exhaust emissions. Lean combustion is a preferred concept for reducing exhaust emissions for meeting stringent emission standards. However lean combustion is associated with increased cycle-by-cycle combustion variation due to combustion instability. The combustion stability under lean mixture conditions could be improved through enhancement of flow characteristics. Effect of engine variables on lean combustion of Spark Ignition (SI) engine is presented, including combustion chamber and inlet port configuration, and ignition system. Use of pre-chamber for lean combustion is one of the feasible method to achieve stable ignition and quick flame propagation. This paper highlights and compares status of various research works carried out in the area of lean burn engines. A critical analysis of reported experimental data is presented in order to substantiate use of lean combustion in SI engine.