Electromagnetic Exhaust Valve Event Optimization for Enhancing Gasoline Engine Performance

Abstract

Abstract. Variable exhaust valve events have the potential to further improve the engine power output, fuel economy and decrease the NOX emissions. Based on the moving coil electromagnetic valve train applied to engine exhaust system, effects of variable exhaust valve events are analyzed in detail and the optimization approaches are carried out. Also with the fully variable intake and exhaust valve train, different internal EGR strategies can be achieved and the contrastive analyses are carried out between combustion chamber recirculation and exhaust port recirculation strategies at same operational condition. Results show that, the optimal exhaust valve opening motion can strengthen both power performance and fuel economy at engine part loads. And two principal EGR strategies are applied in a good combination under variable engine loads. At the engine speed of 2000 r/min, BMEP is about 0.3 MPa and with 30%~35% exhaust port recirculation rate, the BSFC and NOX emissions have decrease over 10% and 85% respectively compare with initial condition.

Design of an Electromagnetic Variable Valve Train with a Magnetorheological Buffer

“…The results show that the thermal efficiency of the engine has an obvious improvement. Xinyu et al [7] realized the optimization of exhaust valve motion by EMVT. The results show that the optimal exhaust valve opening motion can strengthen both the power performance and 1.…”