ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik
Copyright © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Recently Published Articles
- A mechanisms-based reliability model for fatigue of composite laminates
Article first published online: 11 MAY 2015 | DOI: 10.1002/zamm.201500047
Experimental studies of fatigue of composite laminates have clarified the progressive mechanisms underlying this phenomenon. These mechanisms cause degradation in load bearing capacity of laminates and failure occurs when the residual strength equals the maximum applied stress. Assuming that the strength degradation can be related to a measure of the fatigue damage, a two-stage reliability model is developed. A three-parameter Weibull distribution is assumed to describe the initial strength and the probability distributions of residual strengths in both stages and of the fatigue life are derived from this distribution. Experimental data are analyzed to support the results.
- An analytical method for predicting the anti-plane effective magnetoelectroelastic coefficients of composites containing doubly periodic multicoated fibers
Y. L. Xu and J. H. Xiao
Article first published online: 11 MAY 2015 | DOI: 10.1002/zamm.201500003
The present paper deals with the magnetoelectroelastic composites containing a doubly periodic array of multicoated fibers under anti-plane shear loads and in-plane electromagnetic loads. By introducing the generalized eigenstrain, the heterogeneous magnetoelectroelastic medium is equivalent to a homogeneous magnetoelectroelastic medium with the periodically distributed generalized eigenstrains. Then the homogeneous magnetoelectroelastic medium with the generalized eigenstrain is solved analytically under the applied load conditions, the generalized stresses and strains in the fibers, coatings and matrix are derived. Based on the average-field theory, the solutions of the generalized stresses and strains are applied to determine the anti-plane effective magnetoelectroelastic properties of the composites. Two-phase (fiber/matrix) and three-phase (fiber/coating/matrix) magnetoelectroelastic composites are examined, and the comparison between the obtained results and the existing results shows the accuracy of the proposed method. Several four-phase magnetoelectroelastic composites with epoxy matrix are studied, and the influences of the composites microstructures on the effective magnetoelectric coefficient are discussed.
- On the use of the first order shear deformation plate theory for the analysis of three-layer plates with thin soft core layer
Holm Altenbach, Victor A. Eremeyev and Konstantin Naumenko
Article first published online: 6 MAY 2015 | DOI: 10.1002/zamm.201500069
Three-layer laminates with thin soft core layer can be found in many engineering applications. Examples include laminated glasses and photovoltaic panels. For such structures high contrast in the mechanical properties of faces and core requires the use of advanced methods to determine effective material properties of the laminate. In this paper we address the application of the first order shear deformation plate theory to the analysis of laminates with thin and soft core layer. In particular, transverse shear stiffness parameters for three-layered plates with different symmetric configurations are analyzed. For classical sandwiches with thick core layer the result coincides with the Reissner's formula. For the case of thin and compliant core layer the new expression for the effective shear stiffness is derived.
- Semi-active damping optimization of vibrational systems using the parametric dominant pole algorithm
Peter Benner, Patrick Kürschner, Zoran Tomljanović and Ninoslav Truhar
Article first published online: 3 MAY 2015 | DOI: 10.1002/zamm.201400158
We consider the problem of determining an optimal semi-active damping of vibrating systems. For this damping optimization we use a minimization criterion based on the impulse response energy of the system. The optimization approach yields a large number of Lyapunov equations which have to be solved. In this work, we propose an optimization approach that works with reduced systems which are generated using the parametric dominant pole algorithm. This optimization process is accelerated with a modal approach while the initial parameters for the parametric dominant pole algorithm are chosen in advance using residual bounds. Our approach calculates a satisfactory approximation of the impulse response energy while providing a significant acceleration of the optimization process. Numerical results illustrate the effectiveness of the proposed algorithm.
- A positive scheme for diffusion problems on deformed meshes
Xavier Blanc and Emmanuel Labourasse
Article first published online: 3 MAY 2015 | DOI: 10.1002/zamm.201400234
We present in this article a positive finite volume method for diffusion equation on deformed meshes. This method is mainly inspired from , and uses auxiliary unknowns at the nodes of the mesh. The flux is computed so as to be a two-point nonlinear flux, giving rise to a matrix which is the transpose of an M-matrix, which ensures that the scheme is positive. A particular attention is given to the computation of the auxiliary unknowns. We propose a new strategy, which aims at providing a scheme easy to implement in a parallel domain decomposition setting. An analysis of the scheme is provided: existence of a solution for the nonlinear system is proved, and the convergence of a fixed-point strategy is studied.