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Article
Publication date: 1 April 1992

JAROSLAV MACKERLE

This bibliography is offered as a practical guide to published papers, conference proceedings papers and theses/dissertations on the finite element (FE) and boundary element (BE…

Abstract

This bibliography is offered as a practical guide to published papers, conference proceedings papers and theses/dissertations on the finite element (FE) and boundary element (BE) applications in different fields of biomechanics between 1976 and 1991. The aim of this paper is to help the users of FE and BE techniques to get better value from a large collection of papers on the subjects. Categories in biomechanics included in this survey are: orthopaedic mechanics, dental mechanics, cardiovascular mechanics, soft tissue mechanics, biological flow, impact injury, and other fields of applications. More than 900 references are listed.

Details

Engineering Computations, vol. 9 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 10 June 2019

Shuang Wang, Gedong Jiang, Xuesong Mei, Chuang Zou, Xian Zhang and Hao Zhang

Because of the compact structure, short flexspline (FS) harmonic drive (HD) is increasingly used. The stress calculation of FS is very important in design and optimization of HD…

Abstract

Purpose

Because of the compact structure, short flexspline (FS) harmonic drive (HD) is increasingly used. The stress calculation of FS is very important in design and optimization of HD system. This paper aims to study the stress calculation methods for short FS, based on mechanics analysis and finite element method (FEM).

Design/methodology/approach

A rapid stress calculation method, based on mechanics analysis, is proposed for the short FS of HD. To verify the stress calculation precision of short FS, a complete finite element model of HD is established. The results of stress and deformation of short FS in different lengths are solved by FEM.

Findings

Through the rapid calculation method, the analytical relationship between circumferential stress and length of cylinder was obtained. And the circumferential stress has proportional relation with the reciprocal of squared length. The FEM results verified that the rapid stress calculation method could obtain accurate results.

Research limitations/implications

The rapid mechanics analysis method is practiced to evaluate the strength of FS at the design stage of HD. And the complete model of HD could contribute to improving the accuracy of FEM results.

Originality/value

The rapid calculation method is developed based on mechanics analysis method of cylinder and equivalent additional bending moment model, through which the analytical relationship between circumferential stress and length of cylinder was obtained. The complete three-dimensional finite element model of HD takes the stiffness of bearing into consideration, which can be used in the numerical simulation in the future work to improve the accuracy.

Details

Engineering Computations, vol. 36 no. 6
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 April 2005

Jaroslav Mackerle

Ceramic materials and glasses have become important in modern industry as well as in the consumer environment. Heat resistant ceramics are used in the metal forming processes or…

5130

Abstract

Purpose

Ceramic materials and glasses have become important in modern industry as well as in the consumer environment. Heat resistant ceramics are used in the metal forming processes or as welding and brazing fixtures, etc. Ceramic materials are frequently used in industries where a wear and chemical resistance are required criteria (seals, liners, grinding wheels, machining tools, etc.). Electrical, magnetic and optical properties of ceramic materials are important in electrical and electronic industries where these materials are used as sensors and actuators, integrated circuits, piezoelectric transducers, ultrasonic devices, microwave devices, magnetic tapes, and in other applications. A significant amount of literature is available on the finite element modelling (FEM) of ceramics and glass. This paper gives a listing of these published papers and is a continuation of the author's bibliography entitled “Finite element modelling of ceramics and glass” and published in Engineering Computations, Vol. 16, 1999, pp. 510‐71 for the period 1977‐1998.

Design/methodology/approach

The form of the paper is a bibliography. Listed references have been retrieved from the author's database, MAKEBASE. Also Compendex has been checked. The period is 1998‐2004.

Findings

Provides a listing of 1,432 references. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

Originality/value

This paper makes it easy for professionals working with the numerical methods with applications to ceramics and glasses to be up‐to‐date in an effective way.

Details

Engineering Computations, vol. 22 no. 3
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 May 1948

D.M.C.

Within the last two decades great progress has been made in the field of hydrodynamics, both in the theoretical sense as well as the practical. This has been particularly…

Abstract

Within the last two decades great progress has been made in the field of hydrodynamics, both in the theoretical sense as well as the practical. This has been particularly noticeable in the rapid advances made, in aircraft and propeller design, which owes most to the successful application of aerodynamical theory. Not so noticeable, and certainly less obvious, are the results obtained by the application of fluid mechanics in other branches of engineering, as for example, in the design of turbo‐machinery such as turbines, pumps, compressors and that pump‐cum‐turbine arrangement known as the torque converter and the so‐called fluid flywheel. In these latter classes of machinery the more modern theories do not attempt to throw down or displace the older laws, by whose means many successful designs have been accomplished, but on the other hand are direct developments thereof as a result of more intensive study. The most important development of recent years, due to the greater knowledge of fluid mechanics, is adequately illustrated by the amazing progress made in the design and performance of axial compressors. Some thirty years ago, a similar but less spectacular application of fluid mechanics was devised in the form of the Michel or Kingsbury thrust bearing.

Details

Aircraft Engineering and Aerospace Technology, vol. 20 no. 5
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 14 March 2019

Pedro G.P. Leite and Gilberto Gomes

The purpose of this paper is to present the application of the boundary element method (BEM) in linear elastic fracture mechanics for analysis of fatigue crack propagation…

Abstract

Purpose

The purpose of this paper is to present the application of the boundary element method (BEM) in linear elastic fracture mechanics for analysis of fatigue crack propagation problems in mixed-mode (I+II) using a robust academic software named BemCracker2D and its graphical interface BemLab2D.

Design/methodology/approach

The methodology consists in calculating elastic stress by conventional BEM and to carry out an incremental analysis of the crack extension employing the dual BEM (DBEM). For each increment of the analysis, the stress intensity factors (SIFs) are computed by the J-Integral technique, the crack growth direction is evaluated by the maximum circumferential stress criterion and the crack growth rate is computed by a modified Paris equation, which takes into account an equivalent SIF to obtain the fracture Modes I and II. The numerical results are compared with the experimental and/or BEM values extracted from the open literature, aiming to demonstrate the accuracy and efficiency of the adopted methodology, as well as to validate the robustness of the programs.

Findings

The paper addresses the numerical simulation of fatigue crack growth. The main contribution of the paper is the introduction of a software for simulating two-dimensional fatigue crack growth problems in mixed-mode (I+II) via the DBEM. The software BemCracker2D coupled to the BemLab2D graphical user interface (GUI), for pre/post-processing, are very complete, efficient and versatile and its does make relevant contributions in the field of fracture mechanics.

Originality/value

The main contribution of the manuscript is the development of a GUI for pre/post-processing of 2D fracture mechanics problems, as well as the object oriented programming implementation. Finally, the main merit is of educational nature.

Details

International Journal of Structural Integrity, vol. 10 no. 4
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 19 May 2021

Hua-Lin Yang, Xiulong Li, Weiwei Sun, Fang Deng and Jie Du

This paper aims to present the mixed elastohydrodynamic lubrication (EHL) model and obtain the leakage characteristics for the skeleton reciprocating oil seal.

Abstract

Purpose

This paper aims to present the mixed elastohydrodynamic lubrication (EHL) model and obtain the leakage characteristics for the skeleton reciprocating oil seal.

Design/methodology/approach

The model consists of a finite element analysis of the contact pressure, a fluid mechanics analysis of the fluid film, a contact analysis of the asperity contact pressure, a deformation analysis of the seal lip and an iterative numerical simulation process.

Findings

Simulation results show that the leakage is in direct proportion to the seal roughness and speed, and in inverse proportion to the fluid viscosity. Comparisons with the experimental results verify the validity of the mixed EHL model.

Originality/value

This study provides a helpful method to calculate the leakage of the skeleton reciprocating oil seal, which shortens its development cycles.

Details

Industrial Lubrication and Tribology, vol. 73 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 1 March 2005

Geun Woo Kim and Kang Yong Lee

Optimisation of the package design in order to reduce stresses in a plastic small outline J‐lead (SOJ) package and to thereby prevent fractures during the infrared soldering…

Abstract

Purpose

Optimisation of the package design in order to reduce stresses in a plastic small outline J‐lead (SOJ) package and to thereby prevent fractures during the infrared soldering process.

Design/methodology/approach

Finite element (FE) modelling was used, both with and without crack tip‐modelling. A design of experiment (DOE) approach was used to reduce the number of FE models required.

Findings

The optimum design values for minimization of thermal stress and the prevention of fracture were found to be different. The results allow the values of design variables such as the dimensions and material properties of the IC package.

Practical implications

To reduce the stresses and thereby prevent fracture, the values of the Young's modulus and coefficient of thermal expansion of the epoxy moulding compound should be reduced.

Originality/value

The work has used both stress analysis and fracture mechanics analysis along with DOE to identify the design values which simultaneously reduce the thermal stresses and prevent the fracture of the IC package.

Details

Soldering & Surface Mount Technology, vol. 17 no. 1
Type: Research Article
ISSN: 0954-0911

Keywords

Article
Publication date: 1 November 2003

Rama Subba Reddy Gorla and Nagasekhar Reddy Gorla

Fluid flow in a circular pipe and a slider bearing was computationally simulated by finite element methods and probabilistically evaluated in view of the several uncertainties in…

Abstract

Fluid flow in a circular pipe and a slider bearing was computationally simulated by finite element methods and probabilistically evaluated in view of the several uncertainties in the performance parameters. Cumulative distribution functions and sensitivity factors were computed for the flow rate and load bearing capacity of the slider bearing due to the several random variables. These results can be used to quickly identify the most critical design variables in order to optimize the design and make it cost effective. The analysis leads to the selection of the appropriate measurements to be used in fluid flow and to the identification of both the most critical measurements and parameters.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 13 no. 7
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 30 August 2023

Jian Wei, XiaoYue Sun, Jing Tian and CaiHong Liu

This paper aims to study the impact of transient velocity changes on sealing performance during reciprocating sealing processes.

110

Abstract

Purpose

This paper aims to study the impact of transient velocity changes on sealing performance during reciprocating sealing processes.

Design/methodology/approach

Establish a model of transient mixed lubrication, solve the transient Reynolds equation, consider the effect of temperature rise at the seal interfaces, and determine the behavior of the seal interfaces, such as film thickness and fluid pressure. Evaluation with friction and leakage rate, calculate the variation of sealing performance with reciprocating velocity under different working conditions, and verify it through bench experiments.

Findings

Within a reciprocating stroke, the frictional force decreases with increasing velocity, and the frictional force of the outstroke is greater than that of the instroke; at the time of the stroke transition, the fluid pressure is smallest and the rough peak contact pressure is greatest. At present, the dynamic pressure effect of fluids is the largest, and the friction force also increases, which increases the risk of material wear and failure. Friction and leakage increase with increasing pressure and root mean square roughness. As temperature increases, friction increases and leakage decreases. In studying the performance variations of seal components through a reciprocating sealing experiment, it was found that the friction force decreases with increasing velocity, which is consistent with the calculated results and more similar to the calculated results considering the temperature rise.

Originality/value

This study provides a reference for the study of transient sealing performance.

Details

Industrial Lubrication and Tribology, vol. 75 no. 9
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 10 January 2024

Jian Wei, YuXi Xue, Jing Tian and Fei Guo

This paper aims to investigate the effect of frictional heat on the wear of high-speed rotary lip seals in engines.

Abstract

Purpose

This paper aims to investigate the effect of frictional heat on the wear of high-speed rotary lip seals in engines.

Design/methodology/approach

In this research paper, the authors focus on the high-speed rotating lip seal of aircraft engines. Using the hybrid lubrication theory, a thermal-fluid-solid coupled numerical simulation model is established to investigate the influence of parameters such as contact pressure distribution, temperature rise and leakage rate on the sealing performance under different operating conditions. By incorporating the Rhee wear theory and combining simulation results with experimental data, a method for predicting the wear of the rotating seal lip profile is proposed. Experimental validation is conducted using a high-speed rotating test rig.

Findings

The results indicate that as the speed increases, the rise in frictional heat leads to a decrease in the sealing performance of the lip seal contact region. The experimental results show a similar trend to the numerical simulation results, and considering the effect of frictional heat, the predicted wear of the lip seal profile aligns more closely with the actual wear curve. This highlights the importance of considering the influence of frictional heat in the analysis of rotating seal mechanisms.

Originality/value

This study provides a reference for the prediction of wear profiles of engine high-speed rotary lip seals.

Details

Industrial Lubrication and Tribology, vol. 76 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

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