Effect of Split and Timing Injection Techniques on Diesel-Biodiesel Blends Fueled RCCI Engines

Abstract

On reactivity-controlled compression ignition engines, numerical simulations approach were conducted to study the combined effect of the 2nd pulse fraction and dwell time on combustion and emissions characteristics powered by the diesel-biodiesel blends. The Diesel-RK commercial software carried out the simulation the engine was chosen. Meanwhile, the fuel is directly injected through engine cylinder, four stroke, and single cylinder. Simulations were conducted with different dwell times between start of injections of the 1st and 2nd pulses, while the start of injections times of 1st pulse keeping at -40o CA ATDC. Besides, the fuel fraction ratio of the 2nd pulse was changed at 90, 80,70, and 70%, accordingly. In this current study, the peak cylinder pressure and peak cylinder temperature were compared at various boundary conditions. The extracted results extracted from simulation showed that, in contrast to the dwell time 5o CA, a slightly reduction in peak cylinder pressure by 8.9, 7.8, 6.7, and 9.1% for 10, 15. 20, 25o CA respectively. Peak cylinder temperature showed identical trend, its decreased by 9.0, 6.8, 7.8, and 8.8% . Moreover, the results showed that by decreased fuel fraction ratio from 90 to 60%, the peak cylinder pressure increased by 10.1%, while peak cylinder temperature decreased by 7.9%. As a result of the current study, and based on the results of the experimental work published in the literature, it has been consistently demonstrated that the predictive numerical model is reliable..