Showing papers on "Fluid bearing published in 2021"
TL;DR: In this paper, a modified lubrication model considering the influences of journal misalignment is proposed in the theoretical model, and the influence of surface topography and thermal balance effects are incorporated in a theoretical model.
71 citations
TL;DR: The paper presents the characteristics of bearings as well as the basic advantages, disadvantages and possibilities offered by active control of various types of bearings, and possible directions of development of active bearings (ABs).
40 citations
TL;DR: In this paper, a structural and mathematical model of foil air bearing was developed with emphasis on computational time-efficiency for rotor dynamic investigations, and the reduction approach was applied to the non-dimensional model to reduce its dimension and thus its computational costs.
23 citations
TL;DR: In this paper, the authors investigated the excitation mechanisms and contributions of Tribofilm-Asperity Interaction (TAI) that occurs in the hydrodynamic lubrication regime of journal bearings.
23 citations
TL;DR: In this article, the coupled effects of different non-Gaussian properties and misalignments are investigated on the performance of journal bearings, and the results provide the basis for monitoring the conditions of hydrodynamic journal bearings.
17 citations
TL;DR: An analytical design tool is introduced based on anticipatory Life Cycle Assessment (LCA) to clarify when water lubricated bearings are or are not a sustainable alternative, and inform design decisions, and aids bearing designers towards more sustainable designs.
16 citations
01 May 2021
TL;DR: In this article, a comparative numerical study is performed between V-shape protruded, dimple textured, and untextured bearing in terms of load-carrying capacity and coefficient of f
Abstract: The present comparative numerical study is between V-shape protruded, dimple textured, and untextured bearing. The performance parameters in terms of the load-carrying capacity and coefficient of f...
12 citations
11 Feb 2021
TL;DR: In this article, the authors used the Reynolds equation considering the partial wall slip to study the hydrodynamic lubrication performance of partial microgroove water-lubricated bearing.
Abstract: In the present works, the Reynolds equation considering the partial wall slip is used to study the hydrodynamic lubrication performance of Partial Microgroove Water-lubricated Bearings (PMWB). Based on the developed model, the hydrodynamic performances of partial microgroove water-lubricated bearings with three microgroove distributions are systematically compared. The results show that herringbone-groove bearing yields the maximum load capacity, followed by spiral-groove bearings and straight-groove bearings. Furthermore, numerical results also show that wall slip can enhance the load capacity for all three partial microgroove distributions. In addition, the effects of the groove depth and the groove angle, eccentricity ratio and slip arrangement on the lubrication performance of the microgroove bearings are studied. The simulation results indicate that the eccentricity ratio significantly affects the lubrication performance of partial microgroove water-lubricated bearings considering wall slip, while the groove depth and the angle only slightly affect the lubrication performance. Moreover, the slip arrangement is less sensitive to the depth and angle of groove than eccentricity ratio. The parametric study demonstrates that the load capacity of PMWB will decline at a relatively large eccentricity ratio.
12 citations
TL;DR: In this article, the authors present the development of a turbocharger rotor dynamic model, accounting for lateral and axial vibrations and cross-coupling bearing effects, to analyze run down or run up dynamic response.
11 citations
TL;DR: In this article, the time response of a rotating machine subjected to worn hydrodynamic bearings is analyzed to observe the vibration behavior in presence of bearing wear, and an improved and new parametric model is generated to increase simulation accuracy.
10 citations
01 Jun 2021
TL;DR: In this paper, the authors proposed a design and optimization of textures on the surface of crankpin bearing to improve the lubrication efficiency and friction power loss (LE-FPL).
Abstract: The study proposes a design and optimization of textures on the surface of crankpin bearing to improve the lubrication efficiency and friction power loss (LE-FPL). A hydrodynamic lubrication model ...
TL;DR: In this paper, a new approach to model and identify oil supply in hydrodynamic bearing is presented, which is a model-based process that uses the rotor vibration to access the bearing lubrication.
03 Mar 2021
TL;DR: Water-lubricated bearings have attracted increasing attention in the field of high-speed machine tools for their low friction due to low viscosity as discussed by the authors, however, new problems, in particular, insufficien...
Abstract: Water-lubricated bearings have attracted increasing attention in the field of high-speed machine tools for their low friction due to low viscosity. However, new problems, in particular, insufficien...
01 Aug 2021
TL;DR: The bearing geometry has a big impact on the performance of a hydrodynamic thrust bearing and shape optimisation of the bearing surface has been carried out for some time, with Lord R... as discussed by the authors.
Abstract: The bearing geometry has a big impact on the performance of a hydrodynamic thrust bearing. For this reason, shape optimisation of the bearing surface has been carried out for some time, with Lord R...
TL;DR: In this article, a new concept of hydrodynamic bearing is proposed in which the own bearing motion is considered, thus making possible to change the average velocity of the lubricating oil film inside the bearing.
TL;DR: In this article, the combined influence of surface roughness effects and behavior of piezo-viscous shear thinning lubricant has been investigated for non-recessed hole-entry hybrid spherical journal bearings.
TL;DR: In this article, a rotor finite element model combining on-board motions with shaft-stator rub impact is first proposed and validated with a rotor test-rig supported by hydrodynamic bearings and mounted on a multi-axial hydraulic shaker and subject to a harmonic base motion.
25 Mar 2021
TL;DR: In this article, a rotordynamic experiment on a compressor rotor system is presented and the feasibility of gas foil bearings with inhomogeneous bump foils is verified using a push-pull device.
Abstract: In this paper, a rotordynamic experiment on a compressor rotor system is presented and the feasibility of gas foil bearings with inhomogeneous bump foils is verified. A push–pull device is designed...
TL;DR: In this paper, a new look on the solution of the Navier-Stokes equation was proposed to solve an optimization problem and find the optimal viscosity distribution in a fluid-film bearing.
13 Jul 2021
TL;DR: In this article, the sector-shaped tilting pad thrust bearings employing the new micro-structural geometries on pad are employed to reduce power loss, minimum film thickness, and maximum oil temperature.
Abstract: Performance parameters such as power loss, minimum film thickness, and maximum oil temperature of the sector-shaped tilting pad thrust bearings employing the new micro-structural geometries on pad ...
07 Jan 2021
TL;DR: In this paper, the surface waviness of both the journal and the bearing bush and their impact on the static characteristics of the hydrodynamic journal bearing was investigated and the finite difference method was introduced to solve a Reynolds equation and obtain the unknown pressure field.
Abstract: An investigation on the surface waviness of both the journal and the bearing bush and their impact on the static characteristics of the hydrodynamic journal bearing is presented in this paper. The finite difference method is introduced to solve a Reynolds equation and obtain the unknown pressure field. The static characteristics, including the load carrying capacity, attitude angle, end leakage flow rate and frictional coefficient are studied under different waviness parameters. The numerically simulated results indicate that the waviness of the bearing bush may deteriorate or enhance the bearing system, depending on the phase angle. The waviness of the journal causes periodic changes in bearing behavior, owing to the alteration in the phase angle. The profile of the journal and bearing surfaces near the attitude angle determines the performance of the bearing system.
TL;DR: In this paper, the performance of different types of surface texture, including full texture, full texture and partial texture, was evaluated for stability and stiffness tests. And the results showed that the partially textured surface bearing with 60% of textured ratio and 4.9% of area ratio exhibit the best properties, which could decrease the maximum amplitude by 45.8% at 9000rpm.
Abstract: Hydrodynamic bearing is becoming an indispensable component of high-accuracy devices such as high-speed machine tools. Recently, the study of textured surface bearing has become one of the highly researched topics. Among the different types of surface texture, partially textured bearing shows outstanding performances on anti-vibration. However, most of the research focuses on the theoretical models of partial texture. In this paper, several bearings with no texture, full texture and partial texture are fabricated for stability and stiffness tests. The result shows that the partially textured bearings with 60% of textured ratio and 4.9% of area ratio exhibit the best properties, which could decrease the maximum amplitude by 45.8% at 9000 rpm. In addition, the textured surface with the optimal textured ratio of 60% can reduce the static stiffness and improve the dynamic stiffness. Therefore, partially textured bearings are particularly significant to the stability enhancement of the bearing system, which can lead to the performance and security improvement of the sliding bearing in high-speed applications.
TL;DR: In this article, a new rotor support element consisting of a hydrodynamic bearing and a magnetorheological squeeze film damper was proposed to suppress undesirable phenomena induced by rotor rubbing.
01 Jan 2021
TL;DR: In this paper, a theoretical analysis of the challenge for oil-based superlubricity is introduced firstly; then it is the simulation work in this area mainly based on thin-film lubrication model.
Abstract: As lubricating oils and greases are still the most widely used lubricants in practical mechanical systems like bearings or gears, superlubricity enabled by oils is expected to be employed in the existing application environments and operating conditions. However due to the limit of the viscosity, the minimum friction coefficient of conventional oil-based lubricants is typically around 0.01–0.05. In this chapter, a theoretical analysis of the challenge for oil-based superlubricity is introduced firstly; then it is the simulation work in this area mainly based on thin-film lubrication model; in the end, some typical experimentally obtained oil superlubricity systems through thin-film lubrication, hydrodynamic lubrication, boundary lubrication, and mixed lubrication regime are presented.
TL;DR: Results show that nonlinear bearing consideration can improve the machine diagnosis and a mixed-integer gradient-based optimization is presented that considers nonlinear bearings and avoids trial masses.
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19 Nov 2021TL;DR: A wide range of journal bearings applications in the industrial machine, significant efforts have been made by tribology researchers to improve their performance in recent years as discussed by the authors, and they have been used in many applications.
Abstract: Due to the wide range of journal bearings applications in the industrial machine, significant efforts have been made by tribology researchers to improve their performance in recent years. Designing...