According to the requirements of heavy commercial compressed natural gas (CNG) vehicle to satisfy China’s rapid economic development, the authors develop and test a new high energy direct ignition system of heavy CNG engine. Hardware and software of the high energy direct ignition system are designed and debugged. Based on the tradition test bench, an optimal test bench for this CNG engine is established. Ignition advance angle is calibrated and analyzed, which has the economy and power performances effects on CNG engine matched the developed high energy direct ignition system. To test the effects on engine emissions by high energy direct ignition system, ignition control strategy is simplified and optimized. In addition, high ignition energy is directly determined by current time of ignition coil power. A test study about torque, power and fuel consumption of this engine is accomplished. The final test results indicate that this developed high energy ignition direct system can satisfy the comprehensive performance objectives of heavy CNG engine.

As a kind of new renewable energy, biogas is receiving more and more attentions. However, its combustion duration is longer than diesel, which causes the bigger thermal load of engine. A geometry model of a biogas engine’s piston is set up in Proe 4.0. The temperature fields, thermal stress and thermal deformation of the piston are calculated using ANSYS 10.0. The result shows that the thermal load of biogas engine is still within the thermal strength of the material, thus provides supporting evidence for the popularity of biogas.