Performance Optimization And Simulation Of Turbocharged And Lean Burn CNG Engine

Since the national energy-saving and new energy automobile source plan starts, naturalgas vehicles in the country are applied all over the country. However vehicle, parts should beput forward higher requirements on the reliability. Natural gas engine is core part of naturalgas vehicle, and natural gas engine includes CNG engine and LNG engine. CNG engine hasrapidly developed with its low manufacturing cost and less emission of pollutants, at thesame time, the structure, the working process of the optimization and emission of CNGengine control research has become a current research hot spot. This paper selects simulationand test optimization method, carries out corresponding performance optimization andresearch, based on turbocharged and lean burn CNG engine. The main research work isdivided into following four aspects:1. Model built and verification: this paper builds up CNG engine work process modelbased on the basic principle of thermodynamics, the engine principle and gas dynamicsaccording to the actual engine test bench by AVL BOOST software, verifies the modelaccuracy according to previous experimental data. Finally the result error is below5%fortorque, power and fuel consumption rate.2. Structure parameters optimization of turbocharged and lean burn engine: this paperoptimizes structure parameters of turbocharged and lean burn CNG engine, uses the methodof one parameter optimization, simulation and optimization of structure parameters ofcompression ratio and gas distribution phase, discusses the effect of compression ratio forCNG engine torque, power, gas consumption rate, and so on, Finally this paper getsoptimization compression ratio and gas distribution phase based on effect law anddevelopment requirements, which meets engine power, economy performance.3. Control parameters optimization of turbocharged and lean burn engine: this paper uses the one parameter optimal to optimize ignition advance angle and air-fuel ratio,discusses the effect of CNG engine torque, gas consumption rate, exhaust gas temperatureand so on, and gets optimal ignition advance angle and air-fuel ratio scope based on effectlaw and performance advance. Finally this paper gets the optimal ignition advance angle andair-fuel ratio with experiment analysis, which advances performance after optimization.4. Research on turbocharged and lean burn CNG engine emission performance: thispaper studies CNG engine under steady condition, gets data of main emission products andthen studies how ignition time and excess air ratio affect the emissions of CNG engine.