Optimization of Miller Cycle, EGR, and VNT on Performance and NOx Emission of a Diesel Engine for Range Extender at High Altitude

Due to the increasing sales of extended-range hybrid vehicles and increasingly stringent emission regulations for light in China, performance diesel engines range extenders plateau region have attracted attention. In order obtain superior operating at high altitudes, a multi-objective optimization optimal economic point engine was performed an altitude 1960 m. A system model with MC-EGR-VNT (MEV) technology developed using GT-Power based on data bench analyze effects Miller cycle (MC), exhaust gas recirculation (EGR), variable nozzle turbine (VNT) technologies power, economy, high-speed engines. The response surface method (RSM) design carried out rate (MCR), EGR value opening, VNT opening as factors torque, brake-specific fuel consumption (BFSC), nitrogen oxide (NOx) objectives Box Behnken Design (BBD). results showed that torque BFSC remained almost constant, NOx decreased by 59.5% compared original machine. proposed could make MEV achieve good comprehensive performance.