Performance Of Hydrostatic Bearing Research Articles

Coupling effect of partial composite texture and thermal effect on the performance of hydrostatic bearing

AbstractThis work is focused on performance computation of high speed rotor bearing system with partial composite texture. Since its viscosity at varying speeds affects working performance in different partial composite texture, therefore at design and development stage, it is necessary to know the composite texture and thermal effect acting on rotor‐bearing system that causes variation of performance. The effects of partial composite texture size and position on the performance of the bearing are studied. After the optimal structural parameters are determined, the effects of the partial composite texture and fluid thermos structure coupling on the bearing capacity, stiffness, and friction coefficient of the oil film are analysed. The results show that after considering the influence of thermal effect, the performance enhancement of composite texture bearing is better than that of smooth bearing. Considering the temperature effect, the bearing capacity of the composite textured bearing is increased by 51.4% compared with that of the smooth bearing, and the friction coefficient is reduced to 22.4%, which is better than the value without considering the temperature effect, the accuracy of the results is verified by experiments. This study provides a theoretical basis for the design of hydrostatic bearing and improving its performance.

Influence of the distribution position and arrangement of micro-textured on the performance of the hydrostatic bearing

PurposeThe accuracy of the machining process is significantly impacted by the performance of hydrostatic bearings. This paper aims to analyze the influence of micro-textured on the performance of the hydrostatic bearing, and the performance of the bearing is improved by designing the arrangement of micro-textured.Design/methodology/approachDifferent designs have been used while creating micro-textured bearings. The finite element models of bearing with smooth and micro-textured were established and solved using the computational fluid dynamics method. The arrangement scheme of the micro-textured was evaluated by comparing the influence of the distribution position and arrangement of the micro-textured on the bearing performance.FindingsTo improve the performance of the bearing, the bearing capacity was significantly increased, and the friction coefficient of the bearing was decreased when the micro-textured was distributed in the form of an obtuse angle arrangement in the maximum pressure area of the bearing. The experimental findings validate the analysis method.Originality/valueIn this paper, the effect of irregularly arranged micro-textured on bearing performance is investigated to improve the bearing capacity and lubrication status.

Laser direct writing of rose petal biomimetic micro-bulge structure to realize superhydrophobicity and large slip length

Large slip length at the solid-liquid interface is key factor in the performance of hydrostatic bearings. A superhydrophobic biomimetic-structured surface enables the surface with partial slip. Inspired by rose petal micron papillae, a superhydrophobic surface with biomimetic micro-bulge structures was fabricated by laser direct writing. The prepared surface of tin-bronze alloy shows superhydrophobic property, the maximum water contact angle (WCA) was 163°. The structured surfaces exhibited slip lengths of 20 µm and 37 µm for deionized water and VG5 lubricant, and the original smooth surface has no-slip. The slip length increases with the height of the micro-bulge and the viscosity of working fluid, a maximum slip length measured was 165 µm. It was found that the layered structure contributed to the increase in slip length, demonstrating the good drag reduction properties of the prepared superhydrophobic/oleophobic layer surface. This simple and inexpensive method can fabricate superhydrophobic surfaces with large-slip length, which applied to the solid-liquid interface of hydrostatic bearings can improve dynamic and static properties.

Sensitivity analysis of size effect on the performance of hydrostatic bearing

For size effect on solid-liquid interface of hydrostatic bearing oil film gap flow in two-dimension, fluid dynamic method is applied to investigate the influence of size effect on bearing capacity, dynamic stiffness and other performances. With the consideration of size effect, Reynolds equation is modified by adopting velocity slip boundary condition into Reynolds equation. The sensitivity factors are used to make a quantitative and qualitative analysis. Numerical simulation results show that size effect will affect bearing performances to a certain degree and the effect curve of size effect on bearing performances are given. The four maximum oil film pressures reduce with the increase of slip length. The maximum sensitivity of bearing capacity is 81.94%.

Investigation of Stern Plain Bearings for Contra-Rotating Propeller System. 2nd Report. Performance of Hydrostatic Bearings with Pressurized Oil Supplied through Rotating Inner Shaft.

This paper shows the results of an analytical calculation of newly designed hydrostatic bearing with pressurized oil supplied through the inner shaft, and that they are in good agreement with the experimental results in terms of oil film thickness, moment support capability and oil flow rate. This paper also presents the results of tests on a full-sized contra-rotating shafting and bearing simulator tester of 60000 GT bulk carrier ship. Asynchronous contra-rotation was proven to assist CR bearing operation in partly fluid film lubrication region and to prevent severe seizure of it.