The invention relates to a diesel oil ignition
natural gas engine
combustion system and a control method thereof. The diesel oil ignition
natural gas engine
combustion system comprises an engine body,a diesel oil inlet
system, a
natural gas inlet system, a variable cross-section
turbocharger VGT, an
exhaust gas recirculation system EGR, a variable valve
regulator VVT, a dual-fuel ECU, a comprehensive ECU, a computer and a power source, wherein the
exhaust gas recirculation system EGR comprises an EGR
intercooler and an EGR valve. According to the system, according to different operation conditions of an engine, accurate control over the
fuel gas amount is achieved through strategies of adjusting a gas channel and gas injection of a gas injection valve in a cylinder,
mixed gas with different filling amounts and layering states is formed in the cylinder,
thermodynamic state control is coupled on the basis, through combined control of the variable valve
regulator VVT and the exhaust gasrecirculation system EGR and cooperation of different equivalent ratios, stable ignition and controllable
stratified combustion under various working conditions are achieved, the natural gas replacement ratio of a dual-fuel engine is further increased, and efficient and clean
combustion within a wider working condition operation range is achieved.