scholarly journals A Comparative Elastohydrostatic Analysis of CFV- and Capillary-Compensated Multirecess Hydrostatic/Hybrid Journal Bearing Operating with Micropolar Lubricant

2013 ◽  
Vol 2013 ◽  
pp. 1-17 ◽  
Author(s):  
Suresh Verma ◽  
Vijay Kumar ◽  
K. D. Gupta
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Comparative Study ◽  
Elastic Deformation ◽  
Reynolds Equation ◽  
Journal Bearing ◽  
Performance Characteristics ◽  
Constant Flow ◽  
Bearing System ◽  
Flow Valve

A comparative study on the performance characteristics of the flexible multirecess hydrostatic journal bearing system with constant flow valve and capillary restrictors has been presented considering the effect of micropolar parameters. The modified Reynolds equation for the flow of micropolar lubricant through the bearing has been solved using finite element method, and the resulting elastic deformation in the bearing shell has been determined iteratively. The results indicate that the micropolar parameters of the lubricant affect the performance of the flexible multirecess hydrostatic journal bearing system quite significantly.

Analysis of Multirecess Hydrostatic Journal Bearing Operating With Micropolar Lubricant

2009 ◽  
Vol 131 (2) ◽  
Author(s):  
Suresh Verma ◽  
Vijay Kumar ◽  
K. D. Gupta
Keyword(s):  
Reynolds Equation ◽  
Theoretical Study ◽  
Journal Bearing ◽  
Journal Bearings ◽  
Performance Characteristics ◽  
Constant Flow ◽  
The Finite Element Method ◽  
Lubricant Flow ◽  
Wide Range ◽  
Flow Valve

This paper presents a theoretical study of the performance characteristics of a constant flow valve compensated multirecess hydrostatic journal bearings operating with micropolar lubricant. The finite element method and iterative procedure have been used to solve the modified Reynolds equation governing the micropolar lubricant flow in the bearing. The performance characteristics are presented for a wide range of nondimensional load, lubricant flow, and micropolar parameters. It has been observed that the micropolar parameters significantly influence the performance characteristics of the bearing.

A Comparative Thermal Analysis of Slot-Entry and Hole-Entry Hybrid Journal Bearings Lubricated With Non-Newtonian Lubricant

2010 ◽  
Vol 132 (4) ◽  
Author(s):  
H. C. Garg ◽  
Vijay Kumar ◽  
H. B. Sharda
Keyword(s):  
Reynolds Equation ◽  
Energy Equation ◽  
Journal Bearing ◽  
Flow Equation ◽  
Journal Bearings ◽  
Constant Flow ◽  
Viscosity Variation ◽  
Bearing System ◽  
Flow Valve ◽  
Newtonian Behavior

The effect of viscosity variation due to temperature rise and non-Newtonian behavior of the lubricant on the performance of hole-entry and slot-entry hybrid journal bearings system is the focus of this investigation. The performance characteristics of nonrecessed hybrid journal bearings operating with different flow controlling devices, i.e., constant flow valve, capillary, orifice, and slot restrictors, have been compared. Finite element method has been used to solve the Reynolds equation governing the flow of lubricant in the bearing clearance space along with the restrictor flow equation, energy equation and conduction equation using suitable iterative technique. The non-Newtonian lubricant has been assumed to follow the cubic shear stress law. The results indicate that variation in viscosity due to rise in temperature and non-Newtonian behavior of the lubricant affects the performance of nonrecessed hybrid journal bearing system quite significantly. The results further indicate that bearing performance can be improved by selecting a particular bearing configuration in conjunction with a suitable compensating device.

Theoretical investigation of surface texture effects on the performance characteristics of hydrodynamic two-lobe journal bearing

2020 ◽  
Vol 234 (11) ◽  
pp. 1712-1725
Author(s):  
Niranjan Singh ◽  
RK Awasthi
Keyword(s):  
Finite Element Method ◽  
Theoretical Investigation ◽  
Reynolds Equation ◽  
Journal Bearing ◽  
Surface Texturing ◽  
Performance Characteristics ◽  
Performance Parameters ◽  
Eccentricity Ratio ◽  
Static Performance ◽  
Bearing System

In the present work, theoretical investigation has been performed to predict the influence of spherical textures on the performance characteristics of two-lobe journal bearing system. The flow of lubricant in the clearance space between the bearing and the journal is governed by the Reynolds equation assuming the flow is Newtonian and isoviscous. The Reynolds equation is solved using a finite element method and the static performance parameters of circular/two-lobe smooth/textured journal bearing system have been computed with variation in eccentricity ratio, dimple depth and its location. The numerically simulated results reveal that the partial surface texturing can provide better performance when the textures are created in the pressure build-up region of 126°–286° and the dimple aspect ratio is nearly 1.0.

Static and Dynamic Analysis of Capillary Compensated Hydrostatic Journal Bearings by Finite Element Method

1977 ◽  
Vol 99 (4) ◽  
pp. 478-484 ◽  
Author(s):  
D. V. Singh ◽  
R. Sinhasan ◽  
R. C. Ghai
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Journal Bearing ◽  
Dynamic Performance ◽  
Critical Mass ◽  
Equations Of Motion ◽  
Stability Studies ◽  
Static And Dynamic Analysis ◽  
Bearing System ◽  
Element Method

Using finite element method steady state and dynamic performance of a capillary compensated hydrostatic journal bearing have been investigated. For stability studies, the critical mass of the bearing system has been determined by Routh’s criterion. The locus of the journal center has been predicted by discretizing time and numerically integrating the equations of motion governing the journal bearing system.

Nonlinear transient analysis of hole-entry journal bearing with constant flow of micropolar fluids

2018 ◽  
Vol 233 (1) ◽  
pp. 350-368 ◽  
Author(s):  
Kamal Budheeja ◽  
Suresh Verma
Keyword(s):  
Micropolar Fluid ◽  
Journal Bearing ◽  
Stability Margin ◽  
Constant Flow ◽  
Micropolar Fluids ◽  
Stability Point ◽  
Nonlinear Transient ◽  
The Stability ◽  
Bearing System ◽  
Flow Valve

The present work deals with study and analysis of a symmetric hybrid journal bearing compensated with constant flow valve restrictor operating with micropolar fluid from stability point of view. The effect of micropolar parameters on the stability of this journal bearing system is presented on the basis of nonlinear transient model. Finite element method has been used to solve modified Reynolds’ equation for the flow of micropolar fluid through the bearing. Computations are done for the static and dynamic characteristics of hole-entry hybrid journal bearing system. The stability characteristics in terms of critical mass of journal, threshold speed, and frequency of whirl are obtained for journal bearing system operating with Newtonian and micropolar fluids and are compared together. Paths of the journal center in the form of trajectories have also been plotted using the journal center coordinates obtained after solving nonlinear equation of motion by fourth-order Runge–Kutta method to find the stability margin of the considered bearing configuration more precisely and easily. Results indicate that micropolar effect causes significant increase in stability margin of the hybrid journal bearing system especially at higher loads. The results also indicate that lubricant flow through the bearing and type of lubricant should be decided in an appropriate manner for the stability of the constant flow valve compensated hybrid journal bearing system.

Dynamic analysis of a 2-lobe geometrically imperfect journal bearing system

2016 ◽  
Vol 231 (7) ◽  
pp. 934-950 ◽  
Author(s):  
Dharmendra Jain ◽  
Satish C Sharma
Keyword(s):  
Journal Bearing ◽  
Equations Of Motion ◽  
Constant Flow ◽  
Kutta Method ◽  
Transient Motion ◽  
Nonlinear Transient ◽  
Linear And Nonlinear ◽  
Nonlinear Equations Of Motion ◽  
Bearing System ◽  
Flow Valve

The present study is concerned with the linear and nonlinear transient motion analysis of a 2-lobe geometrically imperfect hybrid journal bearing system compensated with constant flow valve restrictor. The trajectories of journal center motion for a geometrically imperfect rotating journal (barrel, bellmouth and undulation type journal) have been numerically simulated by solving the linear and nonlinear equations of motion of journal center using a fourth order Runga–Kutta method. The numerically computed results for the journal center trajectories indicate that the 2-lobe bearing [Formula: see text] is more stable with geometrically imperfect journal as compared to the circular bearing with imperfect journal.

Effect of wear on the performance of hole entry hybrid conical journal bearing employing constant flow valve compensation

2019 ◽  
Vol 233 (9) ◽  
pp. 1277-1292 ◽  
Author(s):  
Sanjay R Pawar ◽  
Vikas M Phalle
Keyword(s):  
Film Thickness ◽  
Reynolds Equation ◽  
Journal Bearing ◽  
Load Capacity ◽  
Radial Clearance ◽  
Constant Flow ◽  
Performance Parameters ◽  
Element Analysis ◽  
Spherical Coordinate ◽  
Flow Valve

Hybrid bearings gets worn gradually during the start and stop operation. This wearing leads to change in the geometry of bearing and affects the radical clearance as well as fluid film thickness. Therefore, these discontinuities in the radial clearance can influence the performance characteristics. With the purpose of preventing irreparable failure state of bearing assembly, it is essential to concentrate on the actual changes in the performance parameters of hole entry hybrid conical journal bearing due to wear. In this context, the main aim of this analysis is to predict the performance of hole entry hybrid conical journal bearing employing constant flow valve compensation. Modified Reynolds equation in spherical coordinate form is used to govern the flow of lubricant in the narrow region between journal and conical bearing. The solution to this Reynolds equation is obtained by finite element analysis with appropriate boundary conditions. This paper summarizes that for a given bearing with constant flow valve as compensating element, the wear causes variation in lubricant film thickness, which strongly affects load capacity, pressure generated, and dynamic performance parameters.

Journal Motion Simulation of Hybrid Journal Bearing Considering Viscosity Variation Due to Temperature Change

Tribology ◽  
2005 ◽  
Author(s):  
Vijay Kumar ◽  
S. C. Sharma ◽  
S. C. Jain
Keyword(s):  
Dynamic Response ◽  
Equilibrium Position ◽  
Journal Bearing ◽  
Critical Mass ◽  
Nonlinear Dynamic Analysis ◽  
Stability Margin ◽  
Linear Analysis ◽  
Constant Flow ◽  
Bearing System ◽  
Flow Valve

A journal bearing system, if journal is disturbed from its equilibrium position, experiences change in the hydrodynamic forces acting on it. This disturbs the equilibrium of the journal and makes its center to whirl around the static equilibrium position. The dynamic response of a journal bearing system under these conditions can be obtained using either linear or non-linear equation of journal motion. The present work is aimed to determine realistic dynamic response of hole-entry hybrid journal bearing system compensated with constant flow valve restrictor. In this paper, the nonlinearized dynamic response of the journal bearing system is studied by considering two cases of journal mass (MJ) with respect to critical mass (Mlc obtained from linear analysis. i.e MJ = Mlc and MJ > Mlc. The deviation in stability margins is established by comparing the results obtained from the linearized and nonlinearized stability analysis for each case namely, isothermal, elastohyrdostatic, thermohydroststic and thermoelastohydrostatic. The coupled solution of Reynold’s, energy, conduction and elasticity equations is obtained using finite element method and the equation of motion is computed using fourth order Runga-Kutta method. The results obtained in the present work for nonlinear dynamic analysis of a constant flow valve compensated hole-entry hybrid journal bearing shows a increase in stability margin as compared to linear analysis for a case when isothermal conditions are assumed and bearing is considered rigid. When variation of viscosity with temperature is considered i.e. THS case, the stability margin is found to be about 20% higher than that estimated by linear analysis.

Effect of Speed on the Performance Characteristics of Non-Recessed Worn Hybrid Conical Journal Bearing for Different Semi Cone Angles

2018 ◽  
Author(s):  
Vikas M. Phalle ◽  
Sanjay R. Pawar ◽  
Sangram S. Patil
Keyword(s):  
Reynolds Equation ◽  
Journal Bearing ◽  
Flow Equation ◽  
Performance Characteristics ◽  
Appreciable Change ◽  
Spherical Coordinate ◽  
Speed Parameter ◽  
Conical Bearing ◽  
Hybrid Bearing ◽  
Flow Valve

The conical fluid film hybrid journal bearing may be developed as a modification to overcome the adverse effects of cylindrical journal bearing configuration. Hybrid bearing also have a capability to take advantage of simultaneous hydrodynamic and hydrostatic action. This paper aims to study analytically the performance characteristics of a non-recessed, worn hybrid conical journal bearing compensated with constant flow valve as restrictor. The Reynolds equation for conical bearing is developed in spherical coordinate system for governing the flow of iso-viscous incompressible fluid in the clearance space of conical journal and bearing and it is solved by finite element method together with restrictor flow equation. Numerically simulated results indicate that appreciable change in the performance characteristics of worn hybrid conical journal bearing with change in speed parameter and they are expected to be quite useful for the bearing designer.

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