Comprehensive analysis of the effects of alternative fuels on diesel engine performance combustion and exhaust emissions: Role of biodiesel, diethyl ether, and EGR

Abstract

The use of petroleum-based fuels in vehicles poses environmental pollution concerns as well as the need to shift towards alternative fuels due to the diminishing availability of petroleum-based fuels in the future. Therefore, biodiesel fuel stands out among the alternative fuels that could be used in diesel engines. However, when biodiesel fuels are used as fuel in engines, the emission values released from the exhaust do not comply with EURO standards. For this purpose, additional measures to prevent emissions must be taken in addition to alternative fuel usage. In this study, two different methods were simultaneously employed to achieve both the use of alternative fuels and compliance with EURO standards in diesel engines. In the first stage of the study, different proportions of diethyl ether were added to biodiesel fuel. In the study's second stage, a 10% EGR application was performed on the intake manifold to achieve EURO standard-level NO emissions from the exhaust. The biodiesel used in the study was obtained from corn oil through transesterification. Diethyl ether was added to biodiesel at 2.5%, 5%, and 7.5% proportions. As a result of the study, improvements were achieved in effective power and efficiency with the addition of biodiesel and diethyl ether, while NO emissions increased compared to standard diesel fuel. Based on the experimental results, the best combination in terms of both performance and NO emissions was achieved with a 5% diethyl ether-biodiesel blend with a 10% EGR application. While both the biodiesel-diethyl ether mixture and EGR application resulted in a 3% decrease in engine torque, NO emissions decreased by up to 70% compared to diesel fuel.