Examining Ethanol-Biodiesel-Diesel Blends: Impact on Diesel Passenger Car Performance and Emissions under Legislative Test Cycles

<div class="section abstract"><div class="htmlview paragraph">Incorporating ethanol and biodiesel into diesel fuel offers substantial benefits from bioenergy perspective. To assess the effect of these alternative fuels, a study was undertaken to evaluate the impact of Ethanol-Biodiesel-Diesel blends (BD7, E2B7, E5B7) on the performance and emissions of a diesel car under Modified Indian Driving Cycle (MIDC), Worldwide Harmonized Light Vehicles Test Cycle (WLTC), wide-open throttle (WOT), and acceleration tests. A four-cylinder 1.5L Common Rail Turbo based diesel passenger car was selected for the study. The test findings revealed that under MIDC conditions, biodiesel blend (BD7) resulted in higher CO emissions compared to neat diesel, but these emissions decreased with the addition of ethanol (E2B7 and E5B7) due to ethanol's embedded oxygen content. While biodiesel lowered THC emissions, these emissions increased when ethanol was added. NOx emissions increased with biodiesel due to its higher cetane number and shorter ignition delay, and this trend persisted with the E5B7 blend. Under WLTC conditions, BD7 showed higher CO emissions. However, THC emissions decreased across all blends compared to neat diesel, while NOx emissions increased. CO2 emissions, on the other hand, decreased with all blends due to their lower carbon content and improved combustion efficiency. Despite a reduction in calorific value, a marginal improvement in fuel economy was observed. In terms of vehicle performance, the vehicle power remained consistent with improved acceleration time with respect to fuel blends. These results highlight the potential of ethanol-biodiesel-diesel blends to reduce CO2 emissions and improve fuel economy, with the challenge of increased NOx. Long duration trials focusing on vehicle durability including fuel system’s performance, are needed to ensure the viability of these blends in diesel vehicles.</div></div>