Performance enhancement and emission reduction of a diesel engine fueled with different biodiesel-diesel blending fuel based on the multi-parameter optimization theory.

[Display omitted] • The orthogonal principal component-optimization method for performance enhancement of the diesel engine is proposed. • An improved chemical kinetics mechanism of 134 species and 475 reactions is developed. • Numerical model of diesel engine is simulated and are compared with the experimental results. • Improvement suggestions for performance enhancement of the diesel engine are proposed. In this work, the biodiesel-diesel blending fuels (B20, B30 and B40) and pure diesel fuel (B0) were employed to investigate the effects of intake pressure and EGR ratio on the performance and emission characteristics of diesel engine. The 3D model is developed by the AVL-Fire coupled Chemkin code. In addition, an improved chemical kinetics mechanism of 134 species and 475 reactions is employed to simulate the fuel combustion process. The results show that the improved model improves the calculation accuracy and the high intake pressure and oxygen content in biodiesel are beneficial for the improvements of performance and emission characteristics. However, the NO emission increases. On the contrary, the EGR effectively reduces NO x emission. Finally, the performance and emission characteristics of diesel engine are optimized by the orthogonal principal component-optimization method. Moreover, the NO x mass fraction is reduced by 78.6 % and the engine power is decreased by 5.60%. Therefore, the reasonable parameter is beneficial for alleviating the conflict between performance and emission characteristics of diesel engine. [ABSTRACT FROM AUTHOR]