A Transient Thermoelastohydrodynamic Study of Steadily Loaded Plain Journal Bearings Using Finite Element Method Analysis

The present paper proposes an advanced bidimensional model necessary to calculate the temperature field in a journal bearing submitted to both rapid and slow start-ups. The model takes into account realistic thermal boundary conditions at fluid film-solid interfaces. The thermoelastic deformations of both the journal and of the bush are also considered and a special attention is paid to the ruptured zone of the film. The Finite Element Method (with upwind techniques whenever necessary) is employed to solve the equations implied by the model. Finally, the theoretical predictions were validated by comparison with experimental data. [S0742-4787(00)02701-6]

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Stress Variation in the Orthodontic Tipping Phenomenon Analysis through the finite element method

Revista de Chimie ◽

10.37358/rc.18.8.6460 ◽

2018 ◽

Vol 69 (8) ◽

pp. 1992-1995

Author(s):

Dan Dragos Sita ◽

Ligia Brezeanu ◽

Cristina Bica ◽

Dana Manuc ◽

Edwin Sever Bechir ◽

...

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Alveolar Bone ◽

Complex Structure ◽

External Action ◽

The Finite Element Method ◽

Stress Variation ◽

Orthodontic Bracket ◽

Method Analysis ◽

Element Method

The purpose of the study is to assess through a FEM (Finite Element Method analysis), the behavior of a complex structure (enamel-tooth-alveolar bone-periodontal ligament-pulp), subjected to an external load through an orthodontic bracket-with forces of various intensities and to determine its influence on the entire structure.It is necessary to analyze the way all elements of the structure take over the external action given by the action of an orthodontic appliance through the brackets and the influence on the inner component -the pulp-inside of which there are the nerve endings.

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The Convergence of the H-P Version of the Finite Element Method with Quasi-Uniform Meshes for Three Dimensional Poisson Problems with Edge Singularity

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.644-650.1551 ◽

2014 ◽

Vol 644-650 ◽

pp. 1551-1555

Author(s):

Jian Ming Zhang ◽

Yong He

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Weighted Sobolev Spaces ◽

Three Dimensional ◽

The Finite Element Method ◽

Smooth Functions ◽

Edge Singularity ◽

Theoretical Predictions ◽

Theoretical Results ◽

Element Method

This paper is concerned with the convergence of the h-p version of the finite element method for three dimensional Poisson problems with edge singularity on quasi-uniform meshes. First, we present the theoretical results for the convergence of the h-p version of the finite element method with quasi-uniform meshes for elliptic problems on polyhedral domains on smooth functions in the framework of Jacobi-weighted Sobolev spaces. Second, we investigate and analyze numerical results for three dimensional Poission problems with edge singularity. Finally, we verified the theoretical predictions by the numerical computation.

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Development of a Polishing Pad for Achieving Flat Workpiece Edge Shape Based on the Finite Element Method Analysis(Machine Elements and Manufacturing)

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C ◽

10.1299/kikaic.75.1108 ◽

2009 ◽

Vol 75 (752) ◽

pp. 1108-1113 ◽

Cited By ~ 2

Author(s):

Toshiyuki ENOMOTO ◽

Wenxiao WANG ◽

Hideki SAWADA ◽

Kenji HIROSE ◽

Norikazu TABATA

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Finite Element Method Analysis ◽

The Finite Element Method ◽

Polishing Pad ◽

Machine Elements ◽

Method Analysis ◽

Element Method

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Analysis of Aerodynamic Journal Bearings With Small Number of Herringbone Grooves by Finite Element Method

Journal of Tribology ◽

10.1115/1.2927320 ◽

1994 ◽

Vol 116 (4) ◽

pp. 698-704 ◽

Cited By ~ 56

Author(s):

D. Bonneau ◽

J. Absi

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Numerical Study ◽

Load Capacity ◽

Journal Bearings ◽

The Finite Element Method ◽

Bearing Number ◽

Comparison Of The Results ◽

Herringbone Grooves ◽

Element Method

A numerical study of gas herringbone grooved journal bearings is presented for small number of grooves. The compressible Reynolds equation is solved by use of the Finite Element Method. The nonlinearity of the discretized equations is treated with the Newton-Raphson procedure. A comparison of the results for a smooth bearing with previously published results is made and the domain of validity of the Narrow Groove Theory is analyzed. Load capacity, attitude angle, and stiffness coefficients are given for various configurations: groove angle and thickness of grooves, bearing number, and that for both smooth and grooved member rotating.

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A study of slot-entry hydrostatic/hybrid journal bearing using the finite element method

Tribology International ◽

10.1016/s0301-679x(99)00032-8 ◽

1999 ◽

Vol 32 (4) ◽

pp. 185-196 ◽

Cited By ~ 34

Author(s):

Satish C Sharma ◽

Vijay Kumar ◽

S.C Jain ◽

R Sinhasan ◽

M Subramanian

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Journal Bearing ◽

The Finite Element Method ◽

Element Method

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Impact Damage Analysis and Experimental Test of Carbon/Epoxy Composite Laminate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1120-1121.590 ◽

2015 ◽

Vol 1120-1121 ◽

pp. 590-592

Author(s):

Hyoh Yun Choi ◽

Yeon Jun Lim ◽

Hyun Jun Cho ◽

Hyun Bum Park

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Composite Laminate ◽

Impact Analysis ◽

Impact Damage ◽

The Finite Element Method ◽

Fem Model ◽

The Impact ◽

Method Analysis ◽

Element Method

In this work, study on impact damage FEM model of composite structure was performed. From the finite element method analysis results of composite laminate, it was confirmed that the results of analysis was reasonable. The velocity of impactor to initiate damage was estimated, and in order to investigate the damage at the predicted velocity, impact analysis using finite element method was performed. According to the impact analysis results of composite laminate, it was confirmed that the damage was generated at the estimated impact velocity. Finally, the comparison of the numerical results with those measured by the experiment showed good agreement.

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Numerical investigation on the static performance of aerostatic journal bearings with different pocket shapes by the finite-element method

Proceedings of the Institution of Mechanical Engineers Part J Journal of Engineering Tribology ◽

10.1177/1350650120979115 ◽

2020 ◽

pp. 135065012097911

Author(s):

Xinglong Chen ◽

James K Mills ◽

Kai Shi ◽

Gang Bao

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Film Thickness ◽

Journal Bearings ◽

Orifice Diameter ◽

Eccentricity Ratio ◽

The Finite Element Method ◽

Area Formula ◽

Static Performance ◽

Element Method

In this work, to improve the static behavior of aerostatic journal bearings, we examine the effect of pockets with different shapes, including the square, rectangular 1, rectangular 2, and circular, manufactured on the surface of the aerostatic journal bearing. The effects of the pocket shapes, pocket area [Formula: see text], eccentricity ratio ɛ, orifice diameter df, average gas film thickness h0, and misalignment angles [Formula: see text] and [Formula: see text] on the static performance are investigated using simulations. The Reynolds equation is solved by the finite-element method in this work. Simulations reveal that the pocket area [Formula: see text], eccentricity ratio ɛ, gas film thickness h0, orifice diameter df, and misalignment angles [Formula: see text] and [Formula: see text] have a significant influence on the load force F and the stiffness K. In general, rectangular 2 pocket bearings are found to perform somewhat better than bearings with other pocket shapes, with the pocket depth set to one-half of h0, when the pocket area [Formula: see text] varies from one-twelfth to one. The pocket area [Formula: see text] should be set according to the average gas film thickness h0 and the orifice diameter df to achieve a better static performance for the bearings. For bearings operated with misalignment angles [Formula: see text] and [Formula: see text], different pocket areas [Formula: see text] should be set according to the pocket shapes for the optimal design.

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Analysis of Spiral-Grooved Gas Journal Bearings by the Narrow-Groove Theory and the Finite Element Method At Large Eccentricities

Journal of Tribology ◽

10.1115/1.4045636 ◽

2020 ◽

Vol 142 (4) ◽

Cited By ~ 1

Author(s):

Elia Iseli ◽

Eliott Guenat ◽

Roger Tresch ◽

Jürg Schiffmann

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Dynamic Pressure ◽

Journal Bearings ◽

The Finite Element Method ◽

Pressure Profiles ◽

Stability Maps ◽

Time Periodic ◽

Good Agreement ◽

Element Method

Abstract A finite groove approach (FGA), based on the finite element method (FEM), is used for analyzing the static and dynamic behavior of spiral-grooved aerodynamic journal bearings at different eccentricities, number of grooves, and compressibility numbers. The results of the FGA are compared with the narrow-groove theory (NGT) solutions. For the rotating-groove case, a novel time-periodic solution method is presented for computing the quasi-steady-state and dynamic pressure profiles. The new method offers the advantage of avoiding time-consuming transient integration, while resolving a finite number of grooves. The static and dynamic solutions of the NGT and FGA approach are compared, and they show good agreement, even at large eccentricities (ε=0.8) and high compressibility numbers (Λ = 40). Stability maps at different eccentricities are presented. At certain operation points, a stability decrease toward larger eccentricities is observed. The largest stability deviations of the NGT from the FGA solutions occur at large groove angle, low number of grooves, and large compressibility numbers.

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