Session: 23-04 Gas Lubricated Journals

Paper Number: 154269

Numerical Model for Determining the Dynamic Parameters of Gas Journal Bearings With Deformable Porous Media 

The application of porous gas bearings in the industrial field started at the beginning of this century. There are several analytical, numerical, and experimental studies that determine the factors that affect the characteristics of the static and dynamic behavior of porous gas bearings. In most of these studies, the structural deformation is neglected.

Porous gas bearings for high loads in industrial applications develop higher pressures in the lubricating gas film between the porous medium and the rotor. The porous medium in the gas bearing is the restrictor that controls the supply airflow to the gas bearing. Since the porous medium has a relatively low elastic modulus, it is necessary to consider the deformation caused by the pressure developed by the lubricant gas film. This is the fluid-structure interaction of the lubricant and porous medium.

Although elastic deformations of the porous medium are in the order of micrometers, it is in that same order of magnitude that the dimensions of the clearance where the maximum load capacity and static stiffness coefficient are obtained. In consequence, the dynamic coefficients are affected by this deformation. Any small change in the dimension of the clearance has a significant effect on the behavior of the porous gas bearing.

This work develops a solution algorithm using finite differences for the fluid flow coupled to the solution of the structural deformations. It analyzes the effect of porous media deformation on dynamic characteristics, including stiffness and damping coefficient (both direct and cross-coupled) for designing porous gas bearings and application in the industrial field. The work also compares results with published literature.

Presenting Author: Azael Duran-Castillo Universidad Autónoma de Querétaro

Presenting Author Biography: Azael is a PhD student who focuses on studying gas bearing for industrial applications.

Authors:

Azael Duran-Castillo Universidad Autónoma de Querétaro
Juan Jauregui Universidad Autonoma de Queretaro
Oscar De Santiago ETU i+D