Characteristics of Diesel/N-Butanol Blend on a Common Rail Diesel Engine with Exhaust Gas Recirculation

Abstract

20% n-butanol is blended in diesel by volume (noted as D80B20) and experiment has been carried out to study the effect on the combustion and emission characteristics based on a common rail diesel engine with exhaust gas recirculation (EGR) system. The results reveal that D80B20 has longer ignition delay, shorter combustion duration and higher maximum in-cylinder temperature than pure diesel (noted as D100). Further, the number concentration and volume concentration of ultrafine particles decrease significantly while NO X emissions increase a little with the addition of n-butanol. When the exhaust gas is induced into cylinder, NO X emissions significantly decrease and ultrafine particles emissions increase. The number geometric mean diameters and volume geometric mean diameters of ultrafine particles increase with EGR ratio. Compared to D100 without EGR, D80B20 with 20% EGR ratio can reduce both NO X and ultrafine particles emissions at 0.14 MPa BMEP and 0.56 MPa BMEP. KEYWORDSn-butanol; ultrafine particles; combustion; emission; common rail diesel engine Abbreviations ACMP Accumulation mode particles AKMP Aitken mode particles BMEP Brake mean effective pressure CA Crank angle CD Combustion duration D100 Pure diesel D80B20 80% diesel and 20% n-butanol by vol. EGR Exhaust gas recirculation EOC End of combustion ID Ignition delay LHV Lower heating value MHRR Maximum heat release rate MT Maximum temperature