Search results

1 – 9 of 9
Article
Publication date: 1 March 1988

B. Kröplin and D. Dinkler

The load carrying capacity of steel structures, built of slender members like bridge cross‐sections, depends on coupled yielding and buckling of the stringers and the plate strips…

Abstract

The load carrying capacity of steel structures, built of slender members like bridge cross‐sections, depends on coupled yielding and buckling of the stringers and the plate strips as well as on the global buckling. Therefore, the common techniques of modelling the limit load by an elasto‐plastic layer model fail. In order to overcome the difficulty a material law is developed, in which local buckling failure and yielding is considered. This is based on an energy function, which describes the elasto‐plastic intermediate and ultimate state of plates and webs dependent on only a few parameters. The application is shown on large scale examples of stiffened steel bridge decks.

Details

Engineering Computations, vol. 5 no. 3
Type: Research Article
ISSN: 0264-4401

Article
Publication date: 5 January 2010

R. Rossi and E. Oñate

The purpose of this paper is to analyse algorithms for fluid‐structure interaction (FSI) from a purely algorithmic point of view.

Abstract

Purpose

The purpose of this paper is to analyse algorithms for fluid‐structure interaction (FSI) from a purely algorithmic point of view.

Design/methodology/approach

First of all a 1D model problem is selected, for which both the fluid and structural behavior are represented through a minimum number of parameters. Different coupling algorithm and time integration schemes are then applied to the simplified model problem and their properties are discussed depending on the values assumed by the parameters. Both exact and approximate time integration schemes are considered in the same framework so to allow an assessment of the different sources of error.

Findings

The properties of staggered coupling schemes are confirmed. An insight on the convergence behavior of iterative coupling schemes is provided. A technique to improve such convergence is then discussed.

Research limitations/implications

All the results are proved for a given family of time integration schemes. The technique proposed can be applied to other families of time integration techniques, but some of the analytical results need to be reworked under this assumption.

Practical implications

The problems that are commonly encountered in FSI can be justified by simple arguments. It can also be shown that the limit at which trivial iterative schemes experience convergence difficulties is very close to that at which staggered schemes become unstable.

Originality/value

All the results shown are based on simple mathematics. The problems are presented so to be independent of the particular choice for the solution of the fluid flow.

Details

Engineering Computations, vol. 27 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 20 April 2015

Nikolay Asmolovskiy, Anton Tkachuk and Manfred Bischoff

Current procedures of buckling load estimation for thin-walled structures may provide very conservative estimates. Their refinement offers the potential to use structure and…

Abstract

Purpose

Current procedures of buckling load estimation for thin-walled structures may provide very conservative estimates. Their refinement offers the potential to use structure and material properties more efficiently. Due to the large variety of design variables, for example laminate layup in composite structures, a prohibitively large number of tests would be required for experimental assessment, and thus reliable numerical techniques are of particular interest. The purpose of this paper is to analyze different methods of numerical buckling load estimation, formulate simulation procedures suitable for commercial software and give recommendations regarding their application. All investigations have been carried out for cylindrical composite shells; however similar approaches are feasible for other structures as well.

Design/methodology/approach

The authors develop a concept to apply artificial load imperfections with the aim to estimate as good as possible lower bounds for the buckling loads of shells for which the actual physical imperfections are not known. Single and triple perturbation load approach, global and local dynamic perturbation approach and path following techniques are applied to the analysis of a cylindrical composite shell with known buckling characteristics. Results of simulations are compared with published experimental data.

Findings

A single perturbation load approach is reproduced and modified. Buckling behavior for negative values of the perturbation load is examined and a pattern similar to a positive perturbation load is observed. Simulations with three perturbation forces show a decreased (i. e. more critical) value of the buckling load compared to the single perturbation load approach. Global and local dynamic perturbation approaches exhibit a behavior suitable for lower bound estimation for structures with arbitrary geometries.

Originality/value

Various load imperfection approaches to buckling load estimation are validated and compared. All investigated methods do not require knowledge of the real geometrical imperfections of the structure. Simulations were performed using a commercial finite element code. Investigations of sensitivity with respect to a single perturbation load are extended to the negative range of the perturbation load amplitude. A specific pattern for a global perturbation approach was developed, and based on it a novel simulation procedure is proposed.

Details

Engineering Computations, vol. 32 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 31 July 2019

Mathieu Olivier and Olivier Paré-Lambert

This paper aims to present a fluid-structure coupling partitioned scheme involving rigid bodies supported by spring-damper systems. This scheme can be used with already existing…

Abstract

Purpose

This paper aims to present a fluid-structure coupling partitioned scheme involving rigid bodies supported by spring-damper systems. This scheme can be used with already existing fluid flow solvers without the need to modify them.

Design/methodology/approach

The scheme is based on a modified Broyden method. It solves the equations of solid body motion in which the external forces coming from the flow are provided by a segregated flow solver used as a black box. The whole scheme is implicit.

Findings

The proposed partitioned method is stable even in the ultimate case of very strong fluid–solid interactions involving a massless cylinder oscillating with no structural damping. The overhead associated with the coupling scheme represents an execution time increase by a factor of about 2 to 5, depending on the context. The scheme also has the advantage of being able to incorporate turbulence modeling directly through the flow solver. It has been tested successfully with URANS simulations without wall law, thus involving thin high aspect-ratio cells near the wall.

Originality/value

Such problems are known to be very difficult to solve and previous studies usually rely on monolithic approaches. To the authors' knowledge, this is the first time a partitioned scheme is used to solve fluid–solid interactions involving massless components.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 7
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 5 April 2019

Corrado Groth, Ubaldo Cella, Emiliano Costa and Marco Evangelos Biancolini

This paper aims to present a fast and effective approach to tackle complex fluid structure interaction problems that are relevant for the aeronautical design.

Abstract

Purpose

This paper aims to present a fast and effective approach to tackle complex fluid structure interaction problems that are relevant for the aeronautical design.

Design/methodology/approach

High fidelity computer-aided engineering models (computational fluid dynamics [CFD] and computational structural mechanics) are coupled by embedding modal shapes into the CFD solver using RBF mesh morphing.

Findings

The theoretical framework is first explained and its use is then demonstrated with a review of applications including both steady and unsteady cases. Different flow and structural solvers are considered to showcase the portability of the concept.

Practical implications

The method is flexible and can be used for the simulation of complex scenarios, including components vibrations induced by external devices, as in the case of flapping wings.

Originality/value

The computation mesh of the CFD model becomes parametric with respect to the modal shape and, so, capable to self-adapt to the loads exerted by the surrounding fluid both for steady and transient numerical studies.

Details

Aircraft Engineering and Aerospace Technology, vol. 91 no. 6
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 23 January 2009

Erol Uzal and Banu Korbahti

The purpose of this paper is to analyse analytically a control scheme in which the resonance frequencies of a rectangular plate is modified by applying a discrete lateral force…

Abstract

Purpose

The purpose of this paper is to analyse analytically a control scheme in which the resonance frequencies of a rectangular plate is modified by applying a discrete lateral force proportional to the displacement of the plate measured at a single point.

Design/methodology/approach

An isotropic, elastic, rectangular, thin plate which is simply supported along all sides is actuated at point (x2, y2) by applying a force, and the displacement is measured at (x1, y1).

Findings

The main outcome is the full analytical solution for the controlled eigenfrequencies and mode shapes which allows a detailed study of the efficiency of the control method proposed.

Originality/value

The present study was made in the form of an exact analytical solution and demonstrates that it is possible to affect the eigenfrequencies and mode shapes of a plate by measuring the displacement and applying a pressure at discrete points on the plate.

Details

Aircraft Engineering and Aerospace Technology, vol. 81 no. 2
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 24 May 2013

Ch. Alk. Apostolopoulos and Vassilios Kappatos

The corrosion of reinforcing steel bars reduces significantly the life and durability of concrete structures. This critical concern causes great losses to the economy and…

Abstract

Purpose

The corrosion of reinforcing steel bars reduces significantly the life and durability of concrete structures. This critical concern causes great losses to the economy and industry. The purpose of this paper is to estimate the effects of corrosion on the tensile mechanical properties of embedded steel bars B500c in concrete.

Design/methodology/approach

The concept is based on the curve fitting modelling, as well the mathematical correlation of the tensile mechanical properties between corroded bare and corroded embedded steel bars. In order to achieve this, extensive experiments were carried out on both bare (Ø8, 10, 12, 16 and 18 mm) and embedded (Ø8 mm) steel bars B500c, which were subjected to artificially accelerated corrosive conditions in a chloride‐rich atmosphere for several exposure times.

Findings

The research results show that the estimation method is available and effective in simulating the tensile mechanical behaviour of corroded reinforcing steel bars B500c.

Originality/value

As far as is known, this is the first time that an advanced data processing technique has been employed to try to find the mathematical correlation of the existing corrosion damage on the residual tensile properties between bare and embedded steel bars. It is argued that these models can be developed in order to reduce the need for expensive experimental investigation in materials.

Details

International Journal of Structural Integrity, vol. 4 no. 2
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 8 May 2017

Bryan Ashenbaum and Arnold Maltz

The purpose of this paper is to develop a purchasing-logistics integration (PLI) conceptualization along two dimensions: mutual responsibility and integrative efforts. This…

1583

Abstract

Purpose

The purpose of this paper is to develop a purchasing-logistics integration (PLI) conceptualization along two dimensions: mutual responsibility and integrative efforts. This conceptualization is then tested as to whether it provides any insights for supplier performance.

Design/methodology/approach

Information-Processing Theory is used to posit hypotheses linking the dimensions of PLI with various measures of supplier performance. Hypotheses are then tested with a dyadic data set of purchasing and logistics managers, using multiple regression methods.

Findings

Purchasing managers found mutual responsibility to positively influence supplier delivery speed, whereas logistics managers found it to positively influence supplier price performance. Generally speaking, purchasing managers perceived a stronger linkage between formal integrative efforts (liaison roles and joint reward systems) and supplier performance, whereas logistics managers perceived this linkage to be stronger for informal integrative efforts such as information exchange and collaboration.

Research limitations/implications

Study results are cross-sectional in nature and consist of three major industry groupings. The dyadic data were analyzed separately to avoid significant data loss.

Practical implications

Supply chain managers will find the areas where purchasing and logistics managers overlap in their perceptions (as well as where they differ) useful. In addition, an understanding of how PLI influences supplier performance should help improve organizational effectiveness.

Originality/value

PLI is a highly important, yet understudied, internal connection. This study provides a useful framework in helping academics and practitioners better understand this crucial internal connection, and how it relates to the performance extracted from suppliers.

Details

The International Journal of Logistics Management, vol. 28 no. 2
Type: Research Article
ISSN: 0957-4093

Keywords

Article
Publication date: 1 October 1996

Kenneth B. Kahn and John T. Mentzer

Suggests that while integration is a term that logistics discusses in an interorganizational context, integration within an interdepartmental integration is not as prevalent…

11565

Abstract

Suggests that while integration is a term that logistics discusses in an interorganizational context, integration within an interdepartmental integration is not as prevalent. Consequently, a common definition for “integration” is lacking. Literature has provided three characterizations: integration represents interaction or communication activities; integration consists of collaborative activities between departments; and integration is a composite of interdepartmental intraction and interdepartmental collaboration. Adopting the composite view, prescribes that managers and researchers consider integration to be a multidimensional process. Proposes a model is based on this perspective to suggest that different logistics situations will require varying degrees of integration via interaction and collaboration. Managerial implications are discussed for each situation.

Details

International Journal of Physical Distribution & Logistics Management, vol. 26 no. 8
Type: Research Article
ISSN: 0960-0035

Keywords

Access

Year

All dates (9)

Content type

1 – 9 of 9