Flexibility Of Bearing Shell Research Articles

Effect of Elasticity on Capillary Compensated Flexible Multi-recess Hydrostatic Journal Bearing Operating with Micropolar Lubricant

This paper presents a theoretical study of the effects of bearing shell deformation upon the performance characteristics of a capillary compensated multi-recess hydrostatic journal bearing system operating with micropolar lubricant. The finite element method has been used to solve the modified Reynolds’ equation governing the micropolar lubricant flow in the bearing and the three dimensional elasticity equations governing the displacement field in the bearing shell. The elasto-hydrostatic performance characteristics of the bearing are presented for various values of micropolar parameters (l m and N 2) and for a wide range of the deformation coefficient $$\bar{C}_{d}$$ which takes into account the flexibility of the bearing shell. The computed results indicate that the influence of the bearing shell flexibility is quite significant on the performance characteristics of recessed hydrostatic journal bearing system operating with micropolar lubricant.

Performance analysis of flexible multirecess hydrostatic journal bearing operating with micropolar lubricant

ABSTRACTThis paper presents the analytical study of the effect of the bearing shell flexibility on the performance of multirecess hydrostatic journal bearing system operating with micropolar lubricant. The modified Reynolds equation for the flow of micropolar lubricant through constant flow valve‐compensated hydrostatic journal bearing has been solved by finite element technique based on Galerkins method, and the resulting elastic deformation in the bearing shell due to fluid‐film pressure has been determined iteratively, in which the deformation coefficient accounts for the bearing shell flexibility. The computed results suggest that the influence of the micropolar effect on bearing performance characteristics is significantly affected by the bearing shell flexibility. Copyright © 2012 John Wiley & Sons, Ltd.

Study of orifice compensated hole-entry hybrid journal bearing considering surface roughness and flexibility effects

The present work describes a theoretical study to demonstrate the combined influence of surface roughness and bearing flexibility on the performance of an orifice compensated hole-entry hybrid journal bearing system. The average Reynold equation governing the flow of lubricant in the clearance space between rough journal and bearing surfaces and 3-dimensional elasticity equation governing the displacement field in the bearing shell have been solved simultaneously using finite element method. The influence of transverse, isotropic and longitudinal roughness patterns on the performance of orifice compensated hole-entry journal bearing configuration have been studied for the various values of surface roughness parameter ( Λ), surface pattern parameter ( γ) and bearing shell deformation coefficient ( D ¯ c ) . The study indicate that the reduction in the bearing characteristic parameters such as load carrying capacity, fluid-film stiffness and damping coefficients due to the bearing shell flexibility effect can be partially compensated in roughened hole-entry flexible journal bearing system by making a proper selection of roughness patterns. The results presented in the study demonstrates that for an accurate prediction of bearing characteristic data, the consideration of combined influence of surface roughness and bearing flexibility effects in the analysis may be more appropriate to use.

A Study of Non-Recessed Hybrid Flexible Journal Bearing With Different Restrictors

For bearings operating under heavy loads, the elastic deformation of bearing surface induced by fluid film pressures can no longer be neglected as it is comparable to the order of magnitude of fluid film thickness. In the present work a theoretical study describing comparative performance of non-recessed hybrid journal bearing using different flow control devices has been carried out by considering bearing shell flexibility into the analysis. The relevant governing equations have been solved using finite element method. The comparative performance of non-recessed hybrid journal bearings of two separate configurations have been studied for various values of bearing flexibility parameter ((Ȼd)). The results have been presented for hole-entry type journal bearings compensated by capillary, orifice and constant flow valve restrictors and for a slot-entry type journal bearing, for the same set of values of operating and geometric parameters. The computed results indicates that in order to get an improved performance of non-recessed journal bearing, a proper selection of bearing flexibility parameter ((Ȼd)) along with type of flow control device (i.e., capillary, orifice, constant flow valve, slot etc.) and type of bearing configuration (symmetric/asymmetric) are essential. Presented as a Society of Tribologists and Lubrication Engineers paper at the ASME/STLE Tribology Conference in Seattle, Washington, October 1–4, 2000

Static and Dynamic Performance Characteristics of Orifice Compensated Hydrostatic Flexible Journal Bearings with Non-Newtonian Lubricants

The combined effect of non-Newtonian lubricant behavior and bearing shell flexibility on the performance of an orifice compensated multirecess hydrostatic/hybrid journal bearing system is studied. The analysis considers the constitutive equations for the flow of a non-Newtonian lubricant through an orifice restrictor, the generalized Reynold's equation governing the flow of lubricant having variable viscosity and 3-D elasticity equations. The computed results demonstrate that loss in bearing performance due to the pseudo-plastic effect of the non-Newtonian lubricant can be mitigated by a proper selection of parameters such as the deformation coefficient (Ȼ4) and non-linearity factor ([Kbar]) or power law index (n).

Influence of elastic effects on the performance of slot-entry journal bearings

Modern high-performance machines require bearings to operate under stringent conditions. For bearings operating under heavy loads, the bearing deformations can no longer be neglected as they are comparable to the order of magnitude of the fluid film thickness. This paper describes the performance of slot-entry hydrostatic/hybrid journal bearings by considering bearing shell flexibility in the analysis. The relevant governing equations have been solved by the finite element method. Slot-entry journal bearings of two separate configurations have been studied over a wide range of bearing operating and geometric parameters. Elastic effects are found to significantly affect the static and dynamic performance characteristics of the bearing studied. The study indicates that, for given operating conditions, to get optimum performance of a bearing proper selection of the bearing flexibility parameter ( C ̄ d ), the concentric design pressure ratio ( β ̄ ∗ ) and the type of bearing configuration (symmetric/asymmetric) are essential.

An elastohydrostatic study of hole-entry hybrid flexible journal bearings with capillary restrictors

The performance characteristics of externally pressurized hole-entry flexible journal bearings with capillary compensation are studied analytically. The finite element method has been used to solve the Reynolds equation governing the lubricant flow in the clearance space of a journal bearing and three-dimensional elasticity equations governing the displacement field in the bearing shell. The bearing performance characteristics are presented for a wide range of values of deformation coefficient ( C d ) which takes into account the flexibility of the bearing shell. The performance characteristics are compared for two hole-entry bearing configurations for the same values of bearing geometric and operating parameters. An example is also provided to enhance understanding of the effects of bearing shell flexibility on the performance characteristics of the two bearing configurations studied.

Performance Characteristics of Externally Pressurized Orifice Compensated Flexible Journal Bearing

This paper presents a theoretical study of the elastohydrostatic performance of an orifice-compensated multirecess journal bearing. The finite element method has been used to solve Reynolds equation governing the lubricant flow in the clearance space of a hydrostatic journal bearing and three dimensional elasticity equations governing the displacement field in the bearing shell. Results have been presented for a wide range of values of deformation coefficient ([Cbar]d). An example is also given to enhance understanding of the effects of bearing shell flexibility on performance characteristics.