Application of CFD Analysis for Rotating Machinery—Part I: Hydrodynamic, Hydrostatic Bearings and Squeeze Film Damper

Abstract

The traditional method for bearing and damper analysis usually involves a development of rather complicated numerical calculation programs that may just focus on a simplified and specific physical model. The application of the general CFD codes may make this analysis available and effective where complex flow geometries are involved or when more detailed solutions are needed. In this study, CFX-TASCflow is employed to simulate various fixed geometry fluid-film bearing and damper designs. Some of the capabilities in CFX-TASCflow are applied to simulate the pressure field and calculate the static and dynamic characteristics of hydrodynamic, hydrostatic, and hybrid bearings as well as squeeze film dampers. The comparison between the CFD analysis and current computer programs used in industry has been made. The results show reasonable agreement in general. Some of the possible reasons for the differences are discussed. It leaves room for further investigation and improvement on the methods of computation.

Application of Computational Fluid Dynamics and Fluid–Structure Interaction Method to the Lubrication Study of a Rotor–Bearing System

“…The half-Sommerfeld boundary condition can be used to find an approximated solution to fluid flow including cavitation by setting the pressure in the divergent field to 0, and therefore has been employed by many researchers when using CFD analysis [13][14][15]. The pressure distributions from the phase change and halfSommerfeld boundary conditions were in agreement with each other (Fig.…”

“…CFD uses the full NavierStokes equations to predict fluid flow and is applicable to complex geometries. Gao et al [13] used a commercially available CFD code to investigate the static and dynamic characteristics of hydrodynamic and hydrostatic bearings, and a squeeze film damper. The same method was applied to a labyrinth seal to test the stability of a rotor-bearing's seal system [14].…”

Experimental Research of Journal Orbit for Water-Lubricated Bearing

“…But compared with the oil film, the low dynamic viscosity forms the low carrying capacity and it is difficult to form the hydrodynamic lubrication in complex lubrication condition. Though there is some progress in the research of lubrication mechanism, the water-lubricated bearing is treated as the independent research object, and most are theoretical [1][2][3][4][5][6][7][8][9] and simulation analysis [10][11][12][13][14][15]; there are few researches for the water-lubricated bearing and rotor system.…”

Performance Evaluation of Hydrodynamic Journal Bearing using Gearbox and Engine Oil (SAE90 and SAE20w50) by Experimental and Theoretical Methods

“…The fluid pressure increases from 0° to certain angle and again reduces from the maximum value to 0°.This is the unique identity of hydrodynamic journal bearing. Conducted research on performance analysis of hydrodynamic and hydrostatic bearings they conducted analysis on a typical cylindrical journal bearing having the dimensions of journal diameter of 50mm and bearing width of 25mm and included angle of 30° (Guo et al 2005). They used the following software CFX-Tasc and VT-FAST to find the maximum pressure, load carrying capacity and attitude of the bearing for a normal mesh and a meshed bearing having a density of 148K both the results were compared.…”