Investigation on combustion and emission characteristics of a CRDI engine fueled with diesel cyclopentanol blends and verification through on-road real-time test

Abstract

In this study, the combustion and emission characteristics of a diesel engine fueled with diesel cyclopentanol blends were experimentally studied through the engine bench test and real-time vehicle test. The results indicated that the cyclopentanol addition weakened the premixed combustion process and accelerated the diffusion combustion process, resulting in an increased peak cylinder pressure and peak combustion temperature. In addition, with the increase of cyclopentanol addition, the ignition delay prolonged, the combustion duration shortened and the heat released more concentratedly. The addition of cyclopentanol decreased both the PM number and volume concentrations significantly, while increased the NOx emission due to the increased peak combustion temperature. At 2000 r/min, CP10 had little effect on inhibiting the nucleation ultrafine particles (≤ 50 nm). Urban, rural and highway roads were considered for on-road real-time vehicle test. The results were consistent with the engine bench test. For urban, rural, and highway areas, the average PN emissions of CP20 were 4.948 × 106, 4.707 × 106, and 3.314 × 106 per cm3, respectively, while those for diesel were 5.755 × 106, 5.547 × 106, and 4.058 × 106 per cm3, respectively.