Numerical study on the application of biodiesel and bioethanol in a multiple injection diesel engine

This research investigates the behavior of ethanol and biodiesel, blended with diesel fuel in a multiple injection engine. Numerical study and engine simulation were carried out using ESE Diesel environment of AVL Fire. The simulations were conducted for 10 and 20% biofuel blends and also, 20 and 30% pilot injection and for two different injection timings. Heat release rate and pressure were compared to the studies in the literature. Agreement between pressure charts was very good while it was acceptable for the heat release rate. For the first case, the injection started at 695 CA while for the second one, it started at 700 CA. The duration of injection for both injection stages lasted 10 CA degree with a dwell angle of 15 CA. According to the results, unlike biodiesel combustion, ethanol combustion resulted in lower chamber temperature and lower NOx emission subsequently. The effect of pilot injection percentage on emissions and heat release rate significantly depends on the injection timing. And finally, as injection start changed from 695 to 700, a noticeable reduction was observed in engine performance and emissions.