Effects of Multiple Injection Strategies on Heavy-Duty Diesel Energy Distributions and Emissions Under High Peak Combustion Pressures

Peak combustion pressures (PCP) are increased in heavy-duty diesel engines to obtain higher thermal efficiency. Fuel injection strategy has been a major measure improve the and emissions of engines. But most existing work multi-injection strategies was not limited by PCP or conducted under lower (∼15 MPa). In this study, an experimental study is further understanding on engine performance relative peak pressure at 20 MPa. The four tested single main injection, pilot-main main-post pilot-main-post injection. effects brake efficiency (BTE) other performances also investigated same NO x conditions. Results indicate that more advanced timing can BTE, while less BTE as it than 120 For double-injection, smaller interval pilot post mass improves emissions. PCPs linearly correlated average temperature, rise rate (PRR), increment PRR about 0.3%, 30 K, 0.1 MPa/CA for every 1 MPa increase PCP, respectively. This means improvement imparts greater mechanical loads materials components. At based optimized strategies, all 42.8%, 0.8 MPa/CA. given emission 17.4 g/kWh approximate have minor distribution fuel energy Therefore, be concluded fewer MPa; purpose reduce reach potentially required temperature aftertreatment devices.