Study on Combustion and Emission Characteristics of Engine Fueled With LNG

The combustion and emission characteristics of a four-cylinder engine fueled with LNG are analyzed. The influence of engine performance changes with engine structure parameters and operating parameters is studied. Results show that ignition timing increases properly can improve LNG engine in-cylinder combustion process, improve engine power performance and economy performance, but NOx emission increases. The best dynamic performance of LNG engine is near the theory of air-fuel ratio. Appropriate compression ratio can improve the engine power performance and economic performance. The influence of compression ratio does not have certain rule to NOx.