No abstract

No abstract

This paper presents comparative energy and exergy analyses of a No. 2 diesel fuel, marine fuel, and four various biodiesel fuels for a four-cylinder, four-stroke, direct-injection diesel engine. The engine was used to obtain the experimental data at full-load conditions for constant 1600 rpm speed. It was found that the firstand second-law efficiencies increased with biodiesel addition and the minimum exergy destruction was obtained at 100% biodiesel fuels. On the other hand, exhaust exergy was found to be inversely proportional to the biodiesel addition. It is also shown with extensive emission analysis that the addition of biodiesel fuels to the standard diesel fuel enhances the emission characteristics of diesel engines.

This study deals with predicting various performance parameters and exhaust emissions of a four-stroke, four-cylinder, direct injection diesel engine fuelled with soybean oil methyl ester (SME) and its 5%, 20% and 50% blends IntroductionSince the advent of the diesel engine over a century ago, many research studies have been conducted to improve the engine performance, decrease the engine fuel consumption and reduce the unwanted exhaust emissions. The oil crisis of the 1970s accelerated the interest of using alternative fuels for diesel engines although diesel fuel has remained as the main fuel. Among these alternatives, the alkyl monoesters of fatty acids from vegetable oils, also named as biodiesels, have received an increasing attention in the past decade. Because biodiesel is a biodegradable and non-toxic alternative fuel with properties very close to diesel fuel, diesel engines can be fuelled with biodiesel without needing a modification. Biodiesels have a higher cetane number, no aromatics, no sulphur and contains 10-11% oxygen by weight. Therefore, the exhaust emissions of a diesel engine fuelled with biodiesel contain less carbon monoxide, hydrocarbon and particulate matter compared to diesel fuel. However, the oxygen content of biodiesel lowers its energy content and increases fuel consumption [1]. The performance and exhaust emissions of diesel engines using various biodiesels have been studied by many investigators [2][3][4][5][6][7][8]. Kalligeros et al. [9] investigated the performance of a diesel engine using the blends of biodiesel and traditional marine diesel fuel. Arkoudeas et al. [10] studied the performance of a compression ignition engine fuelled with blends of JP-8 (jet fuel) and biodiesel. The performance and exhaust emissions of a diesel engine using various fuels for the entire range of operating conditions can be determined by conducting a comprehensive experimental study. However, testing the engine under the all possible operating conditions and fuel cases are both time consuming and expensive. Alternatively, the performance and exhaust emissions of an engine can be modelled using ANNs, which allow the modelling of complex physical phenomena without requiring explicit mathematical representations. However, this new modelling technique can be applied to predict the output parameters of the considered system as long as enough experimental data for training is provided. The ANN technique has been used for modelling the performance of various thermal systems [11−17]. Recently, ANNs have been applied to estimate various performance parameters of internal combustion engines. This approach was used to predict the performance and exhaust emissions of diesel engines [18][19][20] and a gasoline engine [21].