Projeto e dimensionamento de um motor de pistão livre para operação em associação com um gerador elétrico linear

Abstract

Following the idea that the current fossil fuels do not follow the sustainability concept, it comes to light the need to reevaluate the way energy is produced and used. So, there are two aspects: one that presents the concept of renewable energy and the second that seeks higher energy efficiency. The present work is somewhat motivated by both aspects. In terms of energy efficiency, it is proposed the development of a free-piston linear motor combined with a linear electric generator that promises better efficiency in comparison to conventional motors. On the other hand, in terms of renewable energy, it proposes to use as fuel, a gas from synthesis of urban solid waste. A two-stroke, doublepiston engine with Uniflow scavenging, defines the configuration used in this free piston engine generator project. The mathematical model adopted is improved in order to account for mass flows during gas changes, and the geometries of ports and valves. The sensitivity analysis of the parameters, as geometry of the engine, the intake and exhaust times, the dynamic system and the fuel mixture, is performed to note the influences on the engine behavior. An optimization problem is structured in order to find the best configuration that results in the maximum efficiency of the generator set. Further, from the optimized configuration, the peak and average operation conditions of the free piston engine are estimated. This information is used in the material specification and designing of the cylinder, cylinder head, screws, piston, rings and piston pin.