Development of Electronically Controlled Multipoint Injection CNG Engine

This paper presents the designs for intake system, combustion system, CNG supply system, ignition system and electronic control system of CNG (compressed natrural gas) engine. Through investigation and application of lean burn technologies, NOx exhaust emission was controlled effectively without using EGR(exhaust gas recirculation). The CNG engine met Euro Ⅲ(ESC,Euroipean steady cycle) regulation requirement with oxidation catalytic converter. In the meantime, the problem of excessive oil consumption of CNG engine was solved by improving the structures of piston and piston rings. The test results show that CA6SE1-21N CNG engine possesses the rated power of base diesel engine and higher durability.