The randomness in the structure of two-component dense composite materials influences the scalar effective dielectric constant, in the quasistatic limit. A numerical analysis of this property is developed in this paper. The computer-simulation models used are based on both the finite element method and the boundary integral equation method for twoand three-dimensional structures, respectively. ...

An underwater robot is one of the important ocean equipment, and especially its stealth performance has influenced on the vitality in naval warfare. Structure radiation noise as the main source of underwater robot noise, so analysis on vibration and noise radiation is a topic of great concern. The way is used widely that based on fluid-solid coupling modal analysis combined with simulation on v...

of Paper The paper presents an algorithm for physically accurate simulation of elastic deformable objects that are also fast enough for real-time animation. The algorithm uses Boundary Element Method (BEM) (vs. Finite Element Method). The algorithm applies to deformable objects that can be simulated by linear elastic models. It achieves interactive speeds by exploiting coherence in typical inte...

The proposed approach combines the advantages of isogeometric analysis (IGA) and scaled boundary finite element method (SBFEM). The IGA is employed for idealization of the dam structure, while SBIGA is developed for modeling the semi-infinite fluid domain of reservoir and unbounded elastic half-space of the dam foundation. Water compressibility, reservoir boundary wave absorption can be taken i...

The wave based method (WBM) is an efficient deterministic prediction method for the analysis of steady-state acoustic problems. It offers an alternative to the finite element and boundary element method, especially in the mid-frequency range, where these element based methods are impaired by their computational burden. This paper discusses the use of new source formulations in WB models for two...

Approximate numerical techniques, for the solution of the elastic wave scattering problem over semi-infinite domains are reviewed. The approximations involve the representation of the half-space by a boundary condition described in terms of 2D boundary element discretizations. The classical BEM matrices are initially re-written into the form of a dense dynamic stiffness matrix and later approxi...

We study the solution of linear systems that typically arise in discretizations of boundary value problems on a domain with geometrical symmetries. If the discretization is done in an appropriate way, then such a system commutes with a group of permutation matrices. Recently, algorithms have been developed that exploit this special structure, however these methods are limited to the case that t...

A conforming finite element method on polygonal meshes is introduced which handles hanging nodes naturally. Ansatz functions are defined to fulfil the homogeneous PDE locally and they are treated by means of local boundary integral equations. Using a quasi-interpolation operator of Clément type a residual-based error estimate is obtained. This a posteriori estimator can be used to rate the accu...

An object-oriented numerical integration template implementation is presented on the basis of the CCC programming language. Aiming its straightforward application in finite and boundary element methods, the design supports integrand objects of scalar, vector or matrix types, so that a single programming statement is able to integrate element matrices and vectors. The integrand can contain singu...

In this work a novel method for the analysis with trimmed CAD surfaces is presented. The method involves an additional mapping step and the attraction stems from its simplicity and ease of implementation into existing Finite Element (FEM) or Boundary Element (BEM) software. The method is first verified with classical test examples in structural mechanics. Then two practical applications are pre...