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Rotational speed and load-carrying capacity are two mutual coupling factors which affect high precision and stable operation of a hydrostatic thrust bearing. The purpose of this paper is to study reasonable matching relationship between the rotational speed and the load-carrying capacity.

A mathematical model of relationship between the rotational speed and the load-carrying capacity of the hydrostatic bearing with double-rectangle recess is set up on the basis of the tribology theory and the lubrication theory, and the load and rotational speed characteristics of an oil film temperature field and a pressure field in the hydrostatic bearing are analyzed, reasonable matching relationship between the rotational speed and the load-carrying capacity is deduced and a verification experiment is conducted.

By increasing the rotational speed, the oil film temperature increases, the average pressure decreases and the load-carrying capacity decreases. By increasing the load-carrying capacity, the oil film temperature and the average pressure increases and the rotational speed decreases; corresponding certain reasonable matching values are available.

The load-carrying capacity can be increased and the rotational speed improved by means of reducing the friction area of the oil recess by using low-viscosity lubricating oil and adding more oil film clearance; but, the stiffness of the hydrostatic bearing decreases.

Water lubrication is significant for its environmental friendliness. Composite journal bearing is liable to deform for the huge pressure of water film. This paper aims to study the influence of elastic deformation on how lubrication functions in water-lubricated journal bearings and to provide references for designing composite journal bearings.

The combination of computational fluid dynamics and fluid-structure interaction is adopted in this paper to study the lubrication performance of water-lubricated compliant journal bearings. The influences of elasticity modulus and Poisson’s ratio on load-carrying capacity and elastic deformation are studied for different rotational speeds. Predictions in this work are compared with the published experimental results, and the present work agrees well with the experimental results.

A reference whether elastic deformation should be considered for composite journal bearings is proposed under different working conditions. Besides, a reference to determine water-lubricated plain journal bearings dimensions under different loads and rotational speeds is developed with the effect of both elastic deformation and cavitation being accounted.

The present research provides references as to whether elastic deformation should be considered in operation and to determine compliant journal bearings’ dimensions in the design process.

The purpose of this study is to investigate the influence of groove shape on the hydrodynamic characteristics of a journal bearing.

The computational fluid dynamics model also takes into account the cavitation phenomena and thermal effect, which can illustrate the lubrication performance of a journal bearing.

The hydrodynamic simulations of the journal bearing with the different groove shapes are conducted under different operation conditions.

Based on the numerical analysis, the suggestions are presented for groove shape selection and can be used to the design of a journal bearing under the extreme operation condition.

The purpose of this study is to investigate the hydrodynamic characteristics of journal bearings in a high-speed and heavy-load press system by considering thermal influence and cavitation.

A proper and effectual computational method is presented for steady-state analysis of fluid interaction in a rotor-bearing press system by combining computational fluid dynamics techniques.

The influences of eccentricity ratio, rotational speed and oil-film thickness on the hydrodynamic behavior of the journal bearing are studied.

The computational method can be used for creating a precise lubrication design for a journal bearing of a lubrication system.

Journal bearings are used in numerous rotary machines. The load carrying capacity and friction of a bearing have been major concerns in design. Recent developments in surface texturing have showed potential outcomes to improve the tribological characteristics of mating surfaces. This study aims to investigate surface textures, which are transverse to the sliding direction, for frictional response of the journal bearing.

A hydrodynamic lubrication model is considered to evaluate the effect of surface texturing on the performance of a journal bearing at varying operating conditions. The two-dimensional generalized Reynolds equation, coupled with mass-conserving Elrod cavitation algorithm, is solved to evaluate texture-induced variations in tribological performance parameters.

Results have showed remarkable improvements in frictional response. Moreover, micro-textures on the journal surface alter the cavitation response and film-reformation in the hydrodynamic conjunction of the plain bearing.

Operating condition-based comprehensive exhaustive optimization of texture geometry is performed to generate widespread conclusion.

The purposes of the present study are to ensure higher sustainability of journal bearings under different applied loads and to observe bearing performances such as elastic strain, total deformation and stress formation.

A journal bearing test rig was used to determine the effect of the applied load on the bearing friction, film thickness, lubricant film pressure, etc. A steady-state analysis was performed to obtain the bearing performance.

An efficient aspect ratio (L/D) range was obtained to increase the durability or the stability of the bearing while the bearing is in the working condition by using SAE 5W-30 oil. The results from the study were compared with previous studies in which different types of oil and water, such as Newtonian fluid (NF), magnetorheological fluid (MRF) and nonmagnetorheological fluid (NMRF), were used as the lubricant. To ensure a preferable aspect ratio range (0.25-0.50), a computational fluid dynamics (CFD) analysis was conducted by ANSYS; the results show a lower elastic strain and deformation within the preferable aspect ratio (0.25-0.50) rather than a higher aspect ratio using the SAE 5W-30 oil.

It is expected that the findings of this study will contribute to the improvement of the bearing design and the bearing lubricating system.

This paper aims to propose a method for finding the maximum rotational speed of an inclined turntable at which the stability of the bearing oil film is maintained.

The finite difference method was used to solve the Reynolds equation. Variation of bearing capacity of a tilted hydrostatic turret over time was determined. The combined effect of tilt and rotational speed of the turret on the oil film stability was also analyzed.

When the turntable is operated at low speeds with only small angle of tilt, stability of the oil film is maintained. At lower rotational speeds, a smaller angle of tilt improves the bearing capacity and ensures stability of the oil film. Whereas, higher rotational speeds can have a considerable influence on the bearing capacity.

The results demonstrate that the inclination or tilt of the turntable significantly affects the stability of the oil film.

The purpose of this study is to analyze and compare the tribological performances of journal bearings at different conditions through four numerical methods, which are based on the Boussinesq elastic half-space hypothesis or finite element theory.

An elasto-hydrodynamic lubrication (EHL) model of journal bearings is established, with the oil film pressure obtained by the finite difference method, and the deformation of bearing calculated by four different numerical methods, i.e. the direct finite element method (DFEM), influence coefficient method (ICM), fast-Fourier transform method (FFTM) and direct Boussinesq method (DBM). The tribological performances of the journal bearings obtained with the four methods along with the computation efficiency of the methods are discussed.

Under different operation conditions, the tribological performances with the finite element method-based methods (DFEM and ICM) agree with each other, and so do those with the Boussinesq-based methods (FFTM and DBM). Compared with the former two methods, the latter two overestimate the friction coefficient, film thickness and bearing deformation, but underestimate the film pressure, load-carrying capacity and friction force. The above discrepancies depend on the lubricant viscosity, the eccentricity ratio and rotational speed of the shaft and the length–diameter ratio of the bearing. Among the four methods, the FFTM has the best computation efficiency, followed by the DBM and the FEM-based methods.

This study conducts detailed discussions of the numerical methods used in the EHL calculation of journal bearings and gives a helpful reference to analyses and designs of journal bearings.

The purpose of this paper is to investigate and discuss the influence of the pattern, size and orientation of textures on journal bearing load carriage capacity. An important development in load carriage capacity of journal bearings can be obtained by forming regular surface structure in the form of threaded on their shaft surfaces. This is performed both theoretically and experimentally using shafts with textured (threaded) and untextured surfaces. Each screw thread can serve either as a micro‐hydrodynamic bearing in cases of full or mixed lubrication or as a micro reservoir for lubricant in cases of starved lubrication conditions.

The pressure distribution and the load‐carrying capacity are predicted using feed forward architecture of neurons. The inputs to the neurons are a collection of experimental data. These data are used to train the network using the delta‐bar‐delta, batch‐backprop, backprop, and backprop‐rand algorithms. The proposed neural model outperforms the available experimental system in predicting the pressure as well as load‐carrying capacity.

Theoretical models are developed using a neural network approach, and tests are performed, to investigate the potential of threaded textured surfaces in tribological components like mechanical seals, piston rings and journal bearings. In these tests, load carriage capacity is significantly increased with threaded textured shaft surfaces to the shafts with non‐textured surfaces.

The paper discusses a new modelling scheme known as artificial neural networks. A neural network predictor has been employed to analyze the effects of shaft surface profiles in hydrodynamic lubrication of journal bearing.

This study aims to improve the performance of hydrodynamic journal bearings through partial grooving on the bearing surface.

Bearing performance analysis is numerically carried out using the thin film flow physics of COMSOL Multiphysics 5.0 software. Initially, the static performance analysis is carried out for hydrodynamic journal bearing system with smooth surface, and the results of the same are validated with results from the literature. In the later part of the paper, the partial rectangular shape micro-textures are modeled on bearing surface. The effects of partial groove pattern on the bearing performance parameters, namely, fluid film pressure, load carrying capacity, frictional power loss and frictional torque, are studied in detail.

The numerical results show that the values of maximum fluid film pressure, load carrying capacity, frictional power loss and frictional torque are considerably improved due to deterministic micro-textures. Bearing surface with partial groove along 90°-180° region results in 81.9 per cent improvement in maximum fluid film pressure and 75.9 per cent improvement in load carrying capacity as compared with smooth surface of journal bearing, with no increase in frictional power loss and frictional torque. Maximum decrease in frictional power loss and frictional torque is observed for partially grooving along 90°-360° region. The simulations are supported by proof-of-concept experimentation.

This study is useful in the appropriate selection of groove parameters on bearing surface to the bearing performance characteristics.