Effect of Triangular Injection Rate Shape on the Performance of a Reactivity Controlled Compression Ignition Engine

Injection rate shape has an important effect on the performance of internal combustion engines. In this study, the effect of three triangular injection rate shapes, including left triangle, middle triangle, and right triangle, which were distinguished by the parameter a equal to 0, 0.5, and 1, respectively, on the performance of a Reactivity Controlled Compression Ignition (RCCI) engine were investigated and compared with the square injection rate shape. It was realized that by increasing, the gross indicated efficiency (GIE) and nitrogen oxides (NOx) emissions increased, while unburned hydrocarbons (UHC) and carbon monoxide (CO) emissions decreased. The highest GIE and the lowest UHC and CO emissions were obtained by the right triangle, which were 9.9% higher and 27.45% and 25.51% lower than those obtained by the square injection rate shape, while the lowest NOx emissions were obtained by the left triangle, which was 14.15% lower than that obtained by the square injection rate shape.