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Article
Publication date: 1 June 1992

Y.W. KWON

A formulation has been developed for thermo‐elastoviscoplastic finite element analyses of continuous fibre‐reinforced composite plates subject to bending loading using a…

Abstract

A formulation has been developed for thermo‐elastoviscoplastic finite element analyses of continuous fibre‐reinforced composite plates subject to bending loading using a generalized continuum mechanics approach. Such an approach is used to model the non‐homogeneity in a composite, which is constituted by fibres embedded in a matrix material. The present formulation computes the respective stresses occurring in each constituent so that the respective yield criterion and flow rule of each constituent may be used if there is a material yielding in any constituent. Thermo‐elastic deformation of fibre and thermo‐elastoviscoplastic deformation of matrix are considered in the present study because the yield strength of fibre is substantially higher than that of matrix in many cases. Both constituents are assumed to be isotropic so that the von‐Mises yield criterion may be used for viscoplastic yielding of matrix. As numerical examples, a parametric study is performed for thermo‐elastoviscoplastic deformations of laminated composite plates subject to thermal bending loads.

Details

Engineering Computations, vol. 9 no. 6
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 March 1991

Y.W. KWON

An analysis model has been developed for the elasto‐viscoplastic analysis of continuous fibre‐reinforced composite structures. Elastic deformation of fibre and elasto‐viscoplastic…

Abstract

An analysis model has been developed for the elasto‐viscoplastic analysis of continuous fibre‐reinforced composite structures. Elastic deformation of fibre and elasto‐viscoplastic deformation of matrix are considered in the analysis model because the yield strength of matrix is, in general, substantially lower than that of fibre. A finite element formulation is derived for the proposed analysis model. If matrix is assumed homogeneous and isotropic, the von Mises yield criterion is used for viscoplastic yielding. As numerical examples, a parametric study has been performed for elasto‐viscoplastic analysis of unidirectional composite plates subjected to inplane loads.

Details

Engineering Computations, vol. 8 no. 3
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 April 1986

Y.W. Kwon and J.E. Akin

A simple efficient algorithm is presented for an elasto‐plastic analysis of plate bending problems. The element is a mixed isoparametric plate element which includes three moment…

Abstract

A simple efficient algorithm is presented for an elasto‐plastic analysis of plate bending problems. The element is a mixed isoparametric plate element which includes three moment components as unknown variables at each node. This element is very simple to use and gives quite accurate solutions. Moreover, the presented algorithm makes a great contribution to reduction of the computing time.

Details

Engineering Computations, vol. 3 no. 4
Type: Research Article
ISSN: 0264-4401

Article
Publication date: 1 April 1986

Y.W. Kwon and J.E. Akin

A new algorithm to solve contact body problems is presented. The contact boundaries are divided into finite elements, and contact element matrices and vectors are computed using a…

Abstract

A new algorithm to solve contact body problems is presented. The contact boundaries are divided into finite elements, and contact element matrices and vectors are computed using a modified variational principle. The contact conditions are incorporated into the total functional using the Lagrange multiplier method. This algorithm considers surface contacts rather than point contacts, and computes contact tractions directly. The Coulomb friction law is used as the friction condition. A transformation matrix based on static equilibrium is developed to solve extensive sliding problems. This algorithm is extended to the elasto‐plastic analysis and several example problems are presented to demonstrate the algorithm.

Details

Engineering Computations, vol. 3 no. 4
Type: Research Article
ISSN: 0264-4401

Article
Publication date: 26 February 2024

Leonardo Valero Pereira, Walter Jesus Paucar Casas, Herbert Martins Gomes, Luis Roberto Centeno Drehmer and Emanuel Moutinho Cesconeto

In this paper, improvements in reducing transmitted accelerations in a full vehicle are obtained by optimizing the gain parameters of an active control in a roughness road…

Abstract

Purpose

In this paper, improvements in reducing transmitted accelerations in a full vehicle are obtained by optimizing the gain parameters of an active control in a roughness road profile.

Design/methodology/approach

For a classically designed linear quadratic regulator (LQR) control, the vibration attenuation performance will depend on weighting matrices Q and R. A methodology is proposed in this work to determine the optimal elements of these matrices by using a genetic algorithm method to get enhanced controller performance. The active control is implemented in an eight degrees of freedom (8-DOF) vehicle suspension model, subjected to a standard ISO road profile. The control performance is compared against a controlled system with few Q and R parameters, an active system without optimized gain matrices, and an optimized passive system.

Findings

The control with 12 optimized parameters for Q and R provided the best vibration attenuation, reducing significantly the Root Mean Square (RMS) accelerations at the driver’s seat and car body.

Research limitations/implications

The research has positive implications in a wide class of active control systems, especially those based on a LQR, which was verified by the multibody dynamic systems tested in the paper.

Practical implications

Better active control gains can be devised to improve performance in vibration attenuation.

Originality/value

The main contribution proposed in this work is the improvement of the Q and R parameters simultaneously, in a full 8-DOF vehicle model, which minimizes the driver’s seat acceleration and, at the same time, guarantees vehicle safety.

Details

Engineering Computations, vol. 41 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 December 2006

Y.W. Kwon

To develop a technique to couple the lattice Boltzmann method (LBM) and the finite element method (FEM) to solve fluid‐structure interaction (FSI) problems.

1132

Abstract

Purpose

To develop a technique to couple the lattice Boltzmann method (LBM) and the finite element method (FEM) to solve fluid‐structure interaction (FSI) problems.

Design/methodology/approach

The FEM was applied to structural analysis while the LBM was applied to fluid flow analysis. The two techniques were coupled in a staggered manner through interface boundary conditions.

Findings

In order to demonstrate the developed coupling technique, various FSI examples were analyzed and presented. The coupling technique was useful to solve FSI problems.

Originality/value

To the best knowledge of the author, there have been few efforts to couple the two techniques to solve the fluid and flexible structure interaction problems.

Details

Engineering Computations, vol. 23 no. 8
Type: Research Article
ISSN: 0264-4401

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. The finite…

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: 13 July 2012

M.F. Boseman, Y.W. Kwon, D.C. Loup and E.A. Rasmussen

In order to connect a fiberglass composite structure to a steel structure, a hybrid composite made of glass and steel fibers has been studied. The hybrid composite has one end…

Abstract

Purpose

In order to connect a fiberglass composite structure to a steel structure, a hybrid composite made of glass and steel fibers has been studied. The hybrid composite has one end section with all glass fibers and the opposite end section with all steel fibers. As a result, it contains a transition section in the middle of the hybrid composite changing from glass fibers to steel fibers. The purpose of this paper is to examine interface strength at the glass to steel fiber transition section, in order to evaluate the effectiveness of the hybrid composite as a joining technique between a polymer composite structure and a metallic structure.

Design/methodology/approach

The present micromechanical study considers two types of glass to steel fiber joints: butt and overlap joints. For the butt joint, the end shape of the steel fiber is also modified to determine its effect on interface strength. The interface strength is predicted numerically based on the virtual crack closure technique to determine which joint is the strongest under various loading conditions such as tension, shear and bending. Numerical models include resin layers discretely. A virtual crack is considered inside the resin, at the resin/glass‐layer interface, and at the resin/steel‐layer interface. The crack is located at the critical regions of the joints.

Findings

Overall, the butt joint is stronger than the overlap joint regardless of loading types and directions. Furthermore, modification of an end shape of the middle fiber layers in the butt joint shifts the critical failure location.

Originality/value

The paper describes one of a few studies which investigated the interface strength of the hybrid joint made of fiberglass and steel‐fiber composites. This joint is important to connect a polymeric composite structure to a metallic structure without using conventional mechanical joints.

Details

Engineering Computations, vol. 29 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 March 1984

Y.W. Kwon and J.E. Akin

The mixed finite element formulation using the Galerkin method is developed for the small deflection of a plate. This equation requires only linear shape functions to give…

Abstract

The mixed finite element formulation using the Galerkin method is developed for the small deflection of a plate. This equation requires only linear shape functions to give compatibility. Furthermore only two degrees of freedom per node are needed. Hence, the formulated equation has several advantages compared with other methods.

Details

Engineering Computations, vol. 1 no. 3
Type: Research Article
ISSN: 0264-4401

Article
Publication date: 31 March 2021

Jae Youn Chang and Wi-Suk Kwon

This study aims at examining the role of the e-store brand personality congruence/incongruence of a multichannel apparel retailer in the formation of consumers' perceived e-store…

1348

Abstract

Purpose

This study aims at examining the role of the e-store brand personality congruence/incongruence of a multichannel apparel retailer in the formation of consumers' perceived e-store brand fit and e-store patronage intention, based on the concept of image congruence.

Design/methodology/approach

An online survey was conducted with a US national sample of 458 female consumers (20–50 years old) who had shopped for clothing online.

Findings

Results revealed that e-store brand personality incongruence in three personality dimensions had a negative impact on consumers' e-store patronage intention directly as well as indirectly by reducing the consumers' global perception of the e-store brand fit. Further, the retailer's relevance to the consumer moderated the relationship between the perceived e-store brand fit and e-store patronage intention in that this relationship was significantly greater among consumers with a high (vs low) perceived self-relevance of the retail brand.

Practical implications

The findings highlight the importance of symbolically integrated cross-channel brand management for multichannel apparel retailers by clearly identifying their brand personality and carefully crafting it into their e-store interface design and e-store visual merchandising to convey the brand personality.

Originality/value

This study expands the application of image congruence to the cross-channel image congruence phenomenon in multichannel retailing environments by examining the e-store brand image congruence employing both direct and indirect approaches.

Details

Journal of Fashion Marketing and Management: An International Journal, vol. 26 no. 1
Type: Research Article
ISSN: 1361-2026

Keywords

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