A General Method for Calculating the Pressure Distribution and Load Capacity for Finite Hydrodynamic Bearings with Lubrication Films Curved in One Direction

1985 ◽  
Vol 28 (1) ◽  
pp. 54-59 ◽  
Author(s):  
A. E. Curzon
1979 ◽  
Vol 101 (3) ◽  
pp. 381-385 ◽  
Author(s):  
R. S. Gupta ◽  
V. K. Kapur

In this analysis the customary neglected centrifugal effects on the performance of hydrostatic porous thrust bearing with incompressible lubricant has been studied and the effects of their interaction of pressure distribution and load capacity illustrate the possibility of replacement of the nonporous bearing material by porous one.


2019 ◽  
Vol 71 (4) ◽  
pp. 594-602 ◽  
Author(s):  
Haniff Abdul Rahman ◽  
Jaharah A. Ghani ◽  
Wan Mohd Faizal Wan Mahmood ◽  
Mohammad Rasidi Mohammad Rasani

Purpose This study aims to simulate the influence of surface texturing produced via turning process toward pressure distribution and load capacity generation using computational fluid dynamics (CFD). Design/methodology/approach The dimple geometry was obtained via turning process, to be used for future application on piston skirt surfaces. Two cases were studied: a preliminary study using single periodic dimple assuming linear dimple distribution and an application study using multiple periodic dimples to address actual dimple orientation following the turning process. Findings For the first case, the dimple was proven to generate load capacity with regard to untextured surface, owing to the asymmetric pressure distribution. Increasing the Reynolds number, dimple width and dimple depth was found to increase load capacity. For the second case, although load capacity increases via surface texturing, the value was 97.4 per cent lower relative to the first case. This confirmed the importance of doing multiple dimple simulations for real applications to achieve more realistic and accurate results. Originality/value A new concept of dimple fabrication using a low-cost turning process has been developed, with a potential to increase the tribological performance under hydrodynamic lubrication. Previous CFD simulations to simulate these benefits have been done using a single periodic dimple, assuming equal distribution array between dimples. However, due to the different orientations present for dimples produced using turning process, a single periodic dimple simulation may not be accurate, and instead, multiple dimple simulation is required. Therefore, present research was conducted to compare the results between these two cases and to ensure the accuracy of CFD simulation for this type of dimple.


1979 ◽  
Vol 21 (1) ◽  
pp. 25-32 ◽  
Author(s):  
M. Burdekin ◽  
N. Back ◽  
A. Cowley

This paper presents a general method for calculating the pressure distribution and the deformations in machine joints. This method assumes that the components of the joint are connected through finite elements which are defined as a function of the surface finish, material and pressure at the apparent area of contact. The system so established is solved in an iterative manner using the finite-element method, obtaining, as a final result, the pressure distribution at the contacting surfaces of the components and the deformations of the surrounding body. To prove the validity and precision of the theoretical formulation, several examples of joints are considered where the correlation between the calculated and measured deflections is shown to be good.


2011 ◽  
Vol 396-398 ◽  
pp. 886-892
Author(s):  
Ying Jia Wang ◽  
Qi Wu Dong ◽  
Hong Guo ◽  
Shao Qi Cen

In the design of tribology pairs, the Rayleigh step bearing is known as a bearing with the highest load capacity amongst all other possible bearing geometries. This paper mainly discusses a new high-speed bearing with shallow and deep cavities on the inner surface of the bearing, and further the physical phenomena in laminar flow and turbulence regimes was revealed. In doing so, the pressure distribution was calculated first using the continuity equations and then performances in the whole flow domain such as pressure distribution, load-carrying capacity, friction force and friction coefficient were calculated. In addition, a set of optimum geometries are shown to provide the highest load capacity for the Rayleigh step bearing under varied Reynolds number. Finally, associated conclusions were drawn by comparison between results under the coexistence state and under the laminar state.


1996 ◽  
Vol 118 (1) ◽  
pp. 190-200 ◽  
Author(s):  
Luis San Andres

The thermal analysis of flexure-pivot tilting-pad hybrid (combination hydrostatic-hydrodynamic) bearings for cryogenic turbopumps is presented. The advantages of this type of bearing for high speed operation are discussed. Turbulent bulk-flow, variable properties, momentum and energy transport equations of motion govern the flow in the bearing pads. Zeroth-order equations for the flow field at a journal equilibrium position render the bearing flow rate, load capacity, drag torque, and temperature rise. First-order equations for perturbed flow fields due to small amplitude journal motions provide rotordynamic force coefficients. A method to determine the tilting-pad moment coefficients from the force displacement coefficients is outlined. Numerical predictions correlate well with experimental measurements for tilting-pad hydrodynamic bearings. The design of a liquid oxygen, flexure-pad hybrid bearing shows a reduced whirl frequency ratio and without loss in load capacity or reduction in direct stiffness and damping coefficients.


1969 ◽  
Vol 91 (1) ◽  
pp. 194-198
Author(s):  
V. N. Constantinescu

The problem of gas lubrication is examined by taking into account the energy equation and variation of viscosity with temperature. The velocity profiles and the pressure differential equation are deduced. When the temperatures T0, T1 of the two lubricated surfaces are constant, simple corrections can be obtained in order to estimate the influence of unequal temperatures of the two surfaces on pressure distribution, load capacity, and friction stresses in self-acting films and on pressure distribution and mass flow in externally pressurized bearings. However, as the influence of the transversal heat transfer manifests only through the intermediary of the variation of viscosity with temperature, the isothermal analysis can further on be used, provided that one takes a mean value for the viscosity, corresponding to a mean temperature Tm = (T0 + T1)/2.


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