Study on the Effects of Compressed Natural Gas on Engine Performances

Engine bench test research has been done on a JL4JB1 diesel engine fueled with compressed natural gas (CNG), and the power performance, load performance and universal performance were obtained, analyzing the performance changing regulations of CNG engine. The results indicate that the maximum torque turns up at the medium speed when the engine operates at power performance points, and the minimum brake specific gas consumption (BSGC) also comes up at medium speed. When the rotating speed keeps constant, BSGC decreases with the torque increasing, and decreasing largely at small load while a little at high load. From the universal performance curve of CNG engine, we can know that the minimum BSGC is 194g/kW·h.