Analytical Research on Characteristics of Deep-shallow Journal Bearings with Orifice Restrictors

Abstract

Hydrodynamic-static hybrid journal bearing with orifice restrictor is a kind of bearing that the throttling effect is realized by orifice restrictor and the second throttling effect is realized by shallow recess. There is a shortage of the existing theory that can not study the load characteristics which are affected by the recess structure parameters and operation parameters in analytical method. It is inconvenient for engineers to use the computational fluid dynamics software, due to the disadvantage of long period of calculation. On the assumption of subsection linearization of pocket pressure, a method is proposed to analyze the deep-shallow bearing characteristics, such as load capacity, bearing stiffness, flow rate and temperature ascending relationship. The analytical method is used to study bearing characteristics with the different structure parameters and working parameters, such as supply pressure, spindle speed, oil inlet aperture, shallow depth and initial oil film thickness. It is demonstrated that stiffness is close to the biggest value and temperature rising is close to the lowest one, when the shallow depth is thicker than the initial oil film by twice or three times, in the conditions that all other structural parameters and operating parameters are unchanged. The reliability of the analytical method has been verified by comparing experimental results with the analytical values.