Mancal Radial de Deslizamiento: Determinação de Ramos de Soluções Periódicas e Pontos de Bifurcação Complexos

Abstract

In the mechanical engineering moving system's field the radial journal bearing is one of the great interest. It consists of a circular inner cylinder (the rotor) that turns inside a hollow cylinder of slightly larger radius (the stator). The cavity between the cylinders is filled with a lubricant and any load carried by the rotor must be supported by the fluid forces exerted by the lubricant on the rotor. The system can be described by a set of four first order's nonlinear ordinary differential equations which the fluid forces are approximate solution of partial differential equations and shows a great richness of behavior same at the simplest case of cavitation model, autonomous, unforced and balanced-mass rotor system. Rigorous geometrical constraints are impose on the moving of the rotor's center about stator's center to avoid the contact between them. Otherwise, the contact could well result in bearing failure. Starting from the Reynolds approximation for the long bearing the paper uses of
numerical methods for bifurcation problems to calculate Hopf bifurcation points and to obtain branching of periodic orbits that emanate from stationary solutions. The paper also
shows the amplitude and frequency of periodic solutions as a function of rotor's angular velocity for the low, medium and high loads.