Teoria de filme fino aplicada a modelagem matemática de mancais fluidodinâmicos

Abstract

Fluid dynamic bearing modeling has traditionally relied on the classical Reynolds model, which allows for the calculation of the load that can be sustained and the position of the shaft relative to a specific load. This approach is effective for simulations in steady-state or pseudotransient regimes, where the given load is balanced by the determined position. This work proposes a novel approach to modeling these dynamic systems, based on thin film theory. The proposed model is one-dimensional for velocity, pressure, and temperature, providing an average view in the radial direction while accounting for the tangential coordinate and time. The innovation of this model lies in how the shaft's movement is integrated with the fluid through the modeling of stresses between the fluid and the shaft, and between the fluid and the bearing.

The development and validation of the model were based on comparisons with established methods, revealing that the thin film model can effectively simulate tangential flows and provides a precise approximation of pressure, velocity, and temperature fields. Despite the expected differences due to the adaptations necessary to incorporate nonlinear and inertial terms into the linear momentum equations, the results demonstrate the feasibility and potential of the model. The proposal holds promise for enabling the modeling and simulation of shaft-bearing system dynamics in transient regimes with reduced computational cost, due to its one-dimensional nature. The presented results are promising and indicate a significant advancement in fluid dynamic bearing modeling, with expectations to improve the accuracy and efficiency of simulations.