Study of the diesel fuel drop vaporization and combustion at a hydrogen-diesel fuel dual fuelled diesel engine

Abstract The present paper shows the analysis of the results of the theoretical model developed by authors for diesel fuel drops vaporization study, air-diesel fuel-hydrogen mixture forming estimation and diesel fuel drops combustion in the presence of air-hydrogen mixtures set in the cylinder before the start of conventional fuel injection. The model is applied to a single cylinder diesel engine fuelled with diesel fuel and hydrogen, in dual mode by diesel gas method, at the engine speed of 900 rev/min. For a diesel fuel drop the vaporization speed, mixture formation speed, combustion speed, flame radius are presented and analysed. At hydrogen use, the cyclic amount of diesel fuel is reduced and the vaporization duration of the diesel fuel drop is reduced comparative to classic fuelling. At dual fuelling, the combustion of the burning of air-hydrogen mixtures in the vicinity of diesel droplets leads to reduced vaporization time, with 43%, an increased vaporization rate, with 26.9% and an accelerated formation of the mixture between diesel fuel and air-hydrogen mixture. Further, the combustion speed increase with 6.9%, the combustion time is decreased with 6% and the flame radius increase with 6.7%.