The effect of turning off the cylinders of an internal combustion engine on environmental characteristics
Students Name: Hoshovskyi Anatolii Mykolaiovych
Qualification Level: magister
Speciality: Motor Vehicle Transport
Institute: Institute of Mechanical Engineering and Transport
Mode of Study: full
Academic Year: 2022-2023 н.р.
Language of Defence: ukrainian
Abstract: One of the most important issues in the search for development alternatives for a gasoline engine is the search for ways to reduce fuel consumption and reduce harmful emissions into the atmosphere. One of the rapidly developing technologies is cylinder deactivation systems, which are capable of deactivating several cylinders in certain operating modes of the internal combustion engine to save fuel and reduce harmful emissions into the atmosphere. The object of research is the processes that occur in the internal combustion engine of cars under operating conditions with complete and partial cylinder shutdown. The subject of the study is the relationship between cylinder deactivation and environmental characteristics of the internal combustion engine. The purpose of the work is to increase fuel efficiency and reduce the toxicity of the internal combustion engine due to the complete and partial shutdown of the cylinders while the car is moving. An analysis of environmental pollution by internal combustion engines was performed. The main sources of air pollution are internal combustion engines, which are equipped with almost every means of transportation. According to statistical data, the main share of toxic emissions falls on idling and constant load modes. Therefore, cars and trucks in big cities, emitting a large amount of harmful substances, have a negative impact on human life. The methods of reducing the toxicity of engine exhaust gases are analyzed, among them neutralization means prevail, and cylinder shutdown is also used. The existing methods of disconnecting the engine cylinders are considered. To date, there are many ways to disable internal combustion engine cylinders, which give good results in terms of fuel economy, but the disadvantage of such systems is low reliability. It is substantiated that the fuel economy at idle and light loads when part of the cylinders are turned off is determined by the dependence of the indicator efficiency on the load change. The process of calculating effective cylinder deactivation in a multi-cylinder engine and its effect on relative additional fuel consumption is presented. A method of determining the relative additional fuel consumption when the cylinders are disconnected on multi-cylinder engines, caused by the compression work in the disconnected cylinders before the change in the additional energy consumption of the engine, is proposed. The presented method of operation of the internal combustion engine with partial and complete shutdown of its cylinders is an effective way to improve the operation of the engine. In the course of the experiment, it was found that the method of disconnecting the cylinders provides a reduction in the toxicity of exhaust gases in all experimental modes. The greatest effect is achieved in the mode that provides the maximum revolutions of the crankshaft considered in this experiment (3500 min-1). In this mode, during the operation of the engine, one cylinder has the lowest toxicity indicators. In the course of the experiment, the dependence of the change in fuel consumption when its cylinders were turned off at different engine crankshaft rotation frequencies was investigated. The results of the measurements established that the used cylinder shutdown method provides a reduction in fuel consumption in all experimental modes. The greatest effect is achieved at engine crankshaft rotation frequency of 3000 min-1. In this mode, when two cylinders are turned off, the fuel economy is 1.45 l/h, which is about 30%.