Simulation of combustion process in diesel/butanol dual fuel engine.

To investigate the feasibility of diesel engines with high butanol substitution rate (BSR), the performance and emissions of diesel–butanol dual fuel engines are studied numerically. It i based on a four-cylinder diesel engine, which is modified into a diesel–butanol dual fuel engine with port-injected butanol fuel and direct-injected diesel fuel. The simulation is performed using GT-Power software, and simulation results are validated with the experimental data. The engine speeds are set at 1600, 2300, and 3600 rpm, respectively. The engine load is set at 25%, 50%, and 75% engine load, respectively. The BSR varies from 0% to 80% with an interval of 10%. The results show that, with the increase of BSR, the peak cylinder pressure (PCP), and the maximum pressure rise rate (MPRR) decrease, while the brake mean effective pressure (BMEP) and the indicated thermal efficiency (ITE) increase under various working conditions. Among them, the MPRR increases by 9%–12%, while the ITE increases by 6%–7%. In terms of emissions, the nitrogen oxide (NOX) decreases obviously (decrease by 32%–54%), while the carbon monoxide (CO) and the hydrocarbons (HC) decrease slightly (CO: decrease by 4%–10%, HC decrease by 3%–4%). [ABSTRACT FROM AUTHOR]