Otimização numérico / computacional aplicada ao comportamento dinâmico de um mecanismo tipo cursor, biela e manivela estudo de caso para implementação de um motor stirling em sua configuração beta

Abstract

In this work a numerical optimization procedure applied to a four-bar mechanism of cursor type, connecting rod and crank, was implemented with the objective of further use in the development of a Stirling engine prototype. The purpose of this procedure was to obtain a geometrical configuration that potentiates the increase in efficiency associated with the thermodynamic aspects of the prototype, as well as reducing the air pumping losses and forces of inertia. In this application, the methods of genetic algorithms, NSGA II, and Sequential Quadratic Programing, SQP, were used to promote the development of the prototype design through the use of multi-objective functions. The Stirling engine is a mechanical device that has the potential to be used in applications where the goal is to make use of energy that is being wasted, such as a heat source. In this way, the idea that motivates this work is to develop a prototype that is able to harvest the energy contained in the exhaust gas of an internal combustion engine for automotive application. In this configuration, the large temperature difference between the flue gases that pass through the exhaust manifold and the air inside the engine bay has the energetic potential to be used by the Stirling engine so that the work performed can drive an electrical generator. For this application, the Stirling engine has been set in its beta configuration, so that the mechanical work is performed by means of a piston and a displacer operating in the same cylinder which has its hot and cold chambers at each of its ends, respectively. Throughout the development of this work some alternative techniques for the practical implementation of the prototype configuration, which ranged from classical Stirling beta engine with its system of double crank to a variation where the shifter is driven by means of an electromagnetic device controlled by an Arduino Uno microcontroller, were tested