The influence of diesel engine's thermal condition on fuel consumption and smoke of exhaust gases

Abstract

The number of vehicles in the world is growing rapidly. Therefore, the global consumption of crude oil is increasing and its natural resources are being depleted. It causes the rise of oil fuel cost. Constantly rising energy prices and environmental concerns have made energy saving the highest priority for transportation operators. The main goal of vehicles' operation is economy. The fuel consumption of the most popular internal combustion engines depends on various factors, and one of the most important of them is thermal condition. Energy or fuel saving is the main way to reduce operational expenses of vehicles. This paper aims to investigate fuel consumption of 1.9 liter volume direct injection diesel engine and to construct a diagram of the dependence of the amount of smoke in exhaust on the temperature of engine's operation. The temperature was fixed in the engine's crankcase, while the temperature of cooling liquid was measured at four points as well as during the engine's bench testing. Unexpected test results are obtained: when the temperature of exhaust gases rises above 70-75°C, the amount of smoke increases by a few times. Finally, basic conclusions and recommendations are given.