Investigation on static and dynamic characteristics of high-speed and heavy-load tilting pad journal bearings

Abstract

Purpose Multitilting-pad journal bearings (MTPJBs) used in large-scale hydraulic turbines often suffer from complex operating conditions, which greatly influence the overall performance of the rotating machine. The purpose of this study is to establish a thermal-elastic-hydrodynamic lubrication model for MTPJBs that can predict the static and dynamic characteristics of high-speed and heavy-load MTPJBs under different operating conditions. Design/methodology/approach A thermo-elasto-hydrodynamic lubrication model considering the turbulence effect is proposed for high-speed and heavy-load TPJBs, which is solved using the coupled finite difference method and finite element method. The model considered the turbulence effect, thermal energy diffusion, viscosity–temperature–pressure relationship and elastic deformation of the pads. The influences of the operating conditions on static and dynamic characteristics of tilting pad journal bearings were analyzed in depth. Findings The operating conditions have a strong effect on the static properties of the bearings. The dynamic characteristics of the TPJB were the most influenced by the shaft speed. The effects of the load direction on the dynamic properties of the TPJB were much stronger than those of the static characteristics. Originality/value This study used analytical methods and models to provide theoretical guidance for evaluating lubricating characteristics, assembling conditions and overall health.

Lubricating characteristics and sealing performance of mixed TEHD analysis of piston-cylinder interface in the piston pump

“…Furthermore, the piston–cylinder interface is continuously changing owing to cam rotation. Under the assumption that the bushing deformation is linear (Bizarre et al , 2020; Yan and Huang, 2022), the finite element method (FEM) is used to solve bushing thermal elastic deformation. Solving the governing equations can obtain the pressure and temperature distribution, and the discrete pressure and temperature were applied as external loads on the surface of each element.…”

Experimental Study on Low Speed Lubrication Characteristics of Large Tilting Pad Bearings

“…With the development of computer and testing technology, the problems of tilting pad bearings in practical applications are found, dealt with and a new model to solve the problem is established. The mathematical model of fluid lubrication of tilting pad bearings is developed from a simple two-dimensional thermo hydrodynamic analysis model to a complex three-dimensional thermo hydrodynamic analysis model, and further to a complex three-dimensional thermoelastic hydrodynamic analysis model, whose computational accuracy and speed have been continuously improved [6] [7] .The effects of turbulence effect [19] [20] , rotor tilting and misalignment [17] [18] , and cavitation effect on the bearing performance such as power consumption, lubrication characteristics, temperature rise of bearing shell, and dynamic characteristics at high speeds are also considered in the theoretical analysis.…”

Dynamic of a Flexible Rotor-Bearing System Supported by Worn Tilting Journal Bearings Experiencing Rub-Impact

“…They also verified the simulations with experiments, but the dynamic behavior of TPJBs was not studied. Yan and Huang [13] proposed a thermos-elastohydrodynamic lubrication model that considers the turbulence effect in heavy-load TPJBs to study their static and dynamic behavior. They demonstrated that higher shaft speeds reduce the temperature rise of the pads, and the dynamic characteristics of TPJBs are highly influenced by shaft speed and the direction of the dynamic load.…”