The transmission characteristics of wire grid polarizers fabricated in finite apertures are investigated by using a three-dimensional finite-difference time-domain formulation. Specifically, the optical transmissivity and extinction ratio are characterized for a wide variety of geometrical parameters including aperture size in both dimensions, conducting wire fill factor, and polarizer thicknes...

We review the spatial discretization procedure for three high-order, unstructured grid methods recently developed for use within ocean circulation modeling. They are based respectively on spectral finite element and high-order finite volume formulations. We discuss and contrast the three methods in the context of the shallow water equations.

Fornberg and Meyer-Spasche proposed some time ago a simple strategy to correct finite difference schemes in the presence of a free boundary that cuts across a Cartesian grid. We show here how this procedure can be combined with a minimax-based optimization procedure to rapidly solve a wide range of elliptic-type free boundary value problems.

This paper contains a numerical analysis of stability, order of accuracy and consistencyof the staggered grid finite difference scheme, used on the elastic wave-equation, as de-scribed by Levander (1988). 1 Finite Difference Analysis1.1 Analysis of Finite Difference SchemesA given partial differential equation can be solved using finite differences. As an example,conside...

in this study, a numerical model was developed to investigate the two-dimensional heat transfer in a homogenous finite cylinder to predict the local temperature and sterilizing value during caviar pasteurization. a fixed grid finite difference method was used in the solution of heat transfer equations according to crank-nicolson’s scheme. the model was validated by comparison of the experimenta...

In the present paper, applicability of the modified fixed grid finite element method in solution of three dimensional elasticity problems of functionally graded materials is investigated. In the non-boundary-fitted meshes, the elements are not conforming to the domain boundaries and the boundary nodes which are used in the traditional finite element method for the application of boundary condit...

Two of the authors earlier suggested a method of calculating special grid steps for three point finite-difference schemes which yielded exponential superconvergence of the Neumann-to-Dirichlet map. We apply this approach to solve the two-dimensional timedomain wave problem and the 2.5-D elasticity system in cylindrical coordinates. Our numerical experiments exhibit exponential convergence at pr...

A finite difference scheme is produced when the partial derivatives in the partial differential equation(s) governing a physical phenomenon are replaced by a finite difference approximation. The result is a single algebraic equation or a system of algebraic equations which, when solved, provide an approximation to the solution of the original partial differential equation at selected points of ...

In this paper, we present an efficient method of two-grid scheme for the approximation of two-dimensional nonlinear parabolic equations using an expanded mixed finite element method. We use two Newton iterations on the fine grid in our methods. Firstly, we solve an original nonlinear problem on the coarse nonlinear grid, then we use Newton iterations on the fine grid twice. The two-grid idea is...