Modelo dinâmico e termodinâmico para motor linear de pistão livre

Abstract

Subject of several academic research and some applications in the industry, linear machines have great potential to replace conventional internal combustion engines. Such machines make it possible to minimize losses and maximize power, therefore, the study of these machines is of paramount importance for efficient and feasible energy utilization. The direct combination of a free piston engine with a linear generator is called free-piston engine generator (FPEG). It is considered an alternative non-conventional electric power generator. This work aims to develop a mathematical and numerical model of a linear free-piston generator. The modeling consisted of the development of a thermodynamic model, which gives the pressure inside the combustion chamber, and a dynamic model of a spring mass system, which defines the force due to the pressure inside the combustion chamber as excitation. The coupling of both models allowed the study and simulation of the thermal cycle, as well as the analysis of the following parameters: geometric parameters of the engine, pressure, loads, forces and mass / spring assembly. The results obtained were satisfactory when compared to data obtained in the scientific literature.