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Article
Publication date: 1 February 1992

R. BARBOSA and J. GHABOUSSI

A numerical technique is described for the analysis of multiple interacting deformable bodies undergoing large displacements and rotations. Each body is considered an…

Abstract

A numerical technique is described for the analysis of multiple interacting deformable bodies undergoing large displacements and rotations. Each body is considered an individual discrete unit, which is idealized by a finite element model. Discrete finite element models interact with their surroundings through contact stresses, which are continually updated as the elements move and deform. The method of analysis consists of a finite element formulation based on a generalized explicit updated Lagrangian method. This formulation is a general finite element formulation, that permits the large deformation analysis of both continuum and discontinuum systems. Different validations of the proposed method of analysis, including cases that involve very large rotations, as well as some examples that demonstrate the application of the discrete finite element method to problems in rock mechanics are presented and discussed in the paper.

Details

Engineering Computations, vol. 9 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 17 November 2021

Xingxing Fang, Dahan Li, Yucheng Xin, Songquan Wang, Yongbo Guo, Ningning Hu and Dekun Zhang

The purpose of this paper is to systematically study the dynamic contact stress, frictional heat and temperature field of femoral head-on-acetabular cup contact pairs in a…

Abstract

Purpose

The purpose of this paper is to systematically study the dynamic contact stress, frictional heat and temperature field of femoral head-on-acetabular cup contact pairs in a gait cycle.

Design/methodology/approach

In this paper, four common femoral head-on-acetabular cup contact pairs are used as the research objects, mathematical calculations and finite element simulations are adopted. The contact model of hip joint head and acetabular cup was established by finite element simulation to analyze the stress and temperature distribution of the contact interface.

Findings

The results show that the contact stress of the head-on-cup interface is inversely proportional to the contact area; high contact stress directly leads to greater frictional heat. However, hip joints with metal-on-polyethylene or ceramic-on-polyethylene paired interfaces have lower frictional heat and show a significant temperature rise in one gait cycle, which may be related to the material properties of the acetabular cup.

Originality/value

Previous studies about calculating the interface frictional heat always ignore the dynamic change process in the contact load and the contact area. This study considered the dynamic changes of the contact stress and area of the femoral head-on-acetabular cup interface, and four common contact pairs were systematically analyzed.

Details

Industrial Lubrication and Tribology, vol. 73 no. 10
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 11 April 2016

Dhaval B. Shah, Kaushik M. Patel and Ruchik D. Trivedi

The purpose of this paper is to describe a method permitting the creation of a realistic model of spherical roller bearing with the aim of determining contact stress and…

Abstract

Purpose

The purpose of this paper is to describe a method permitting the creation of a realistic model of spherical roller bearing with the aim of determining contact stress and fatigue life based on dynamic loading conditions. The paper also aims to recognize the effect of tolerance values on contact stress and fatigue life. Motion and load transmission in spherical roller bearing occurs within the assembly by elliptical curved contacting surfaces. The stress produced by the transmitted load would be very high because of least contacting area between these surfaces.

Design/methodology/approach

The paper describes a methodology to determine contact stress using analytically as well as finite element method for spherical roller bearing. The comparison for the both each approach for contact stress at different loading condition is carried out. Prediction of fatigue life based on dynamic loading conditions for bearing is also determined using finite element model. The effect on induced contact stress and fatigue life by varying tolerances on inner race dimensions have been found out.

Findings

The paper suggests that the maximum stress produces at the start or end of the contacting arc under static loading condition in spherical roller bearing. The analytical and finite element approach is in good agreement. The fatigue life prediction is useful for selecting loading conditions for various applications of double row spherical roller bearing. Tolerance level at inner ring raceway radius is kept high because of manufacturing constrain of complex curvature geometric shape.

Research limitations/implications

The present approach does not consider dynamic loading conditions for contact stress analysis. Therefore, researchers are encouraged to analyze the effect of wear, lubrication and other tribological aspects on bearing life.

Originality/value

The paper includes determination of contact stress and prediction of fatigue life for spherical roller bearing using analytical as well as finite element approach. The tolerance values at inner race are identified as per manufacturing constraint based on contact stress and fatigue life.

Details

Industrial Lubrication and Tribology, vol. 68 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 8 January 2018

Ye Zhou, Caichao Zhu, Huaiju Liu, Chaosheng Song and Zufeng Li

Coatings are widely used in gears to keep interface from wearing excessively. The purpose of this paper is to study the effect of coating properties and working conditions…

Abstract

Purpose

Coatings are widely used in gears to keep interface from wearing excessively. The purpose of this paper is to study the effect of coating properties and working conditions on the pressure, the shear traction, stresses as well as the fatigue life of spur gear.

Design/methodology/approach

A numerical contact fatigue life model of a coated spur gear pair under elastohydrodynamic lubrication (EHL) is developed based on the characteristics of gear geometry and kinematics, lubrication conditions and material properties. Frequency response functions and the discrete convolute and fast Fourier transform (DC-FFT) algorithm are applied to obtain elastic deformation and stress. Mutil-axial fatigue criteria are used to evaluate the contact fatigue life based upon the predicted time-varying stress fields of coated bodies.

Findings

The maximum Mises stress decreases while the fatigue life increases as the coating modulus decreases. A thinner coating leads to a longer life and a smaller maximum Mises stress for hard coatings. The load has more significant effect on the contact fatigue life of soft coatings.

Originality/value

The developed model can be used to evaluate the contact fatigue life of coated gear under EHL and help designers analyze the effect of coating elastic modulus and thickness on the contact pressure, film thickness and stress.

Details

Industrial Lubrication and Tribology, vol. 70 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 1 April 2007

M.H. Hojjati and M. Kazemi Esfe

Contact problems are central to solid mechanics as contact is the principal method of applying loads to a deformable body and the point with resulting stress concentration…

Abstract

Contact problems are central to solid mechanics as contact is the principal method of applying loads to a deformable body and the point with resulting stress concentration is often the most critical point within the body. This paper presents a finite element model for the elastic contact between two cylinders at several positions. The effects of friction and surface roughness have been considered. The contact between two skew cylinders is also investigated. Results from finite element model show a good agreement with those of analytical solutions available in the literature. It was seen that the geometry of contacting bodies and orientation of applied load effect highly on contact stresses. Although the effect of surface roughness was seen to be more than that of friction, both of them can be assumed negligible in elastic contact problems.

Details

Multidiscipline Modeling in Materials and Structures, vol. 3 no. 4
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 19 July 2019

Bingqi Li, Zhenyu Zhang, Xiaogang Wang and Xiaonan Liu

The behavior of joints has a significant effect on the stability of water conveyance tunnel. The purpose of this paper is to study the contact and friction at the joint of…

Abstract

Purpose

The behavior of joints has a significant effect on the stability of water conveyance tunnel. The purpose of this paper is to study the contact and friction at the joint of the tunneling segment lining and establish its contact friction model. At the same time, the stress and deformation characteristics at the joint of the segment under hydrostatic load are analyzed.

Design/methodology/approach

In this study, the contact and friction in a bolted joint are examined using shear testing. The feasibility of the proposed model is verified by a numerical simulation of tests and a theoretical analysis. Accordingly, the effect of joints on the lining is explored under internal hydrostatic loading.

Findings

The results show that the openings of tunnel segments in joints gradually expand from the positions of the inner and outer edges to the location of the bolt. Moreover, the stress concentration zone is formed at the bolt. Under hydraulic loading, the opening displacement at the joint increases as the water pressure increases; nevertheless, it does not exceed engineering requirements. When the water pressure of the tunnel lining joint reaches 0.5 MPa, the opening of the joint slowly increases. When the water pressure exceeds 0.7 MPa, the opening of the joint rapidly and significantly increases.

Originality/value

Contact and friction in a bolted joint were examined using shear testing. A cohesive zone model of bolted joints was proposed based on test results. The influence of joint behavior on the stability of water conveyance tunnel was studied.

Details

Engineering Computations, vol. 36 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 17 July 2019

Pantelis G. Nikolakopoulos, Kyriakos Grigoriadis and Anastasios Zavos

The purpose of this paper is to focus on the creation of an isothermal elastic ring-liner model to highlight, through stresses, the occurrence of the plastic deformation…

Abstract

Purpose

The purpose of this paper is to focus on the creation of an isothermal elastic ring-liner model to highlight, through stresses, the occurrence of the plastic deformation in certain crank angles under extreme dry lubrication conditions.

Design/methodology/approach

The stresses that are exported from this analysis are pointing out not only the necessity for an elastoplastic model to be created, but also the importance of predicting the correct friction coefficient, as pointed out by both the contact surface stress and that in depth of the two bodies in contact.

Findings

The comparison between the finite element model and the adhesion mathematical model of Johnson, Kendall and Roberts seals the importance to calculate the interaction forces, acting on the common solid surface, in the pursuit of defining a propriate contact patch. Additionally, a three-dimensional ring model is built, highlighting the importance of the modeling surface’s micro asperities for a solid stress analysis. Also, numerical experiments are conducted, in contact with the cylinder and a piston ring made of an iron alloy and of two different plating materials, such us Chromium (Cr) and Chromium‒Nickel Alloy (CrN). The ability to calculate the stress concentration factor is also described.

Originality/value

A three-dimensional ring model is built, highlighting the importance of the modeling surface’s micro asperities for a solid stress analysis. Also, numerical experiments are conducted, in contact with the cylinder and a piston ring made of an iron alloy and of two different plating materials, such us Chromium (Cr) and Chromium‒Nickel Alloy (CrN). The ability to calculate the stress concentration factor is also described.

Details

International Journal of Structural Integrity, vol. 10 no. 3
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 1 January 1992

ZHI‐HUA ZHONG and JAROSLAV MACKERLE

Contact problems are among the most difficult ones in mechanics. Due to its practical importance, the problem has been receiving extensive research work over the years…

Abstract

Contact problems are among the most difficult ones in mechanics. Due to its practical importance, the problem has been receiving extensive research work over the years. The finite element method has been widely used to solve contact problems with various grades of complexity. Great progress has been made on both theoretical studies and engineering applications. This paper reviews some of the main developments in contact theories and finite element solution techniques for static contact problems. Classical and variational formulations of the problem are first given and then finite element solution techniques are reviewed. Available constraint methods, friction laws and contact searching algorithms are also briefly described. At the end of the paper, a bibliography is included, listing about seven hundred papers which are related to static contact problems and have been published in various journals and conference proceedings from 1976.

Details

Engineering Computations, vol. 9 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 9 January 2017

Mitul Thakorbhai Solanki and Dipak Vakharia

The purpose of this paper is to present a finite element analysis (FEA) which shows the comparison between a layered cylindrical hollow roller bearing and hollow roller bearing.

Abstract

Purpose

The purpose of this paper is to present a finite element analysis (FEA) which shows the comparison between a layered cylindrical hollow roller bearing and hollow roller bearing.

Design/methodology/approach

In this work, FEA is carried out to solve the elastic contact between a layered cylindrical hollow roller and flat contact for different hollowness percentages ranging from 10 to 80 per cent. Graphical solution is developed to determine the optimum hollowness of a cylindrical roller bearing for which induced bending stress should be within endurance limit of the material.

Findings

Different parameters such as von Mises stress, contact pressure, contact width and deformation are shown here.

Originality/value

The value of this research work is the calculation of contact width and other parameters using FEA for layered cylindrical hollow roller bearing.

Details

Industrial Lubrication and Tribology, vol. 69 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 1 February 1984

Billy Fredriksson, Bo Torstenfelt and Nils Endahl

The importance of contact and friction problems in different application areas is discussed. Methods and algorithms for numerical solutions using the finite element method…

Abstract

The importance of contact and friction problems in different application areas is discussed. Methods and algorithms for numerical solutions using the finite element method are presented. Both elastic and elastic plastic materials are included as well as combination of contact and crack problems. The methods are applied to practical applications such as bolted joints, lugs and roller bearings.

Details

Engineering Computations, vol. 1 no. 2
Type: Research Article
ISSN: 0264-4401

1 – 10 of over 56000