This paper studies the enhanced efficiency of the field strength coupled into slots by using the finite difference time domain method. The coupled field strength with the different slots shape, size, and polarization direction is assisted, some useful rules are concluded. The easiest to form enhanced efficiency of field strength is rectangular slots, square slots are the second, and the most di...

Discontinuous Galerkin Time Domain Methods for Acoustics and Comparison with Finite Difference Time Domain Methods

in this paper, a new numerical method for solving time-fractional diffusion equations is introduced. for this purpose, finite difference scheme for discretization in time and chebyshev collocation method is applied. also, to simplify application of the method, the matrix form of the suggested method is obtained. illustrative examples show that the proposed method is very efficient and accurate.

This paper examines formulation of the discretization schemes for diffusion process simulation that allow coarse grid spacings in the areas of exponentially varying concentrations and fluxes. The method of integral identities is used as a common framework for exponential fitting of both the finite difference and finite element schemes. An exponentially fitted finite difference scheme, with disc...

In a fluid-saturated porous medium, an electromagnetic (EM) wavefield induces an acoustic wavefield due to the electrokinetic effect. A potential geophysical application of this effect is electroseismic (ES) logging, in which the converted acoustic wavefield is received in a fluid-filled borehole to evaluate the parameters of the porous formation around the borehole. In this paper, a finite-dif...

The phase error in finite-difference (FD) methods is related to the spatial resolution and thus limits the maximum grid size for a desired accuracy. Greater accuracy is typically achieved by defining finer resolutions or implementing higher order methods. Both these techniques require more memory and longer computation times. In this paper, new modified methods are presented which are optimized...

Article history: Received 20 January 2014 Received in revised form 28 August 2014 Accepted 19 November 2014 Available online 26 November 2014

in this paper, a new algorithm for studying elastic wave propagation in the phononic crystals is presented. at first, the displacement-based forms of elastic wave equations are derived and then the forms are discretized using finite difference method. so the new algorithm is called the displacement-based finite difference time domain (dbfdtd). three numerical examples are computed with this met...

designing a power splitter with five ports has been shown in this article. in order to prevent the direct coupling between waveguides, a t-shaped structure with an appropriate distance has been used. the coupling between the parallel photonic crystal waveguides is based on multimode interference, while selecting the output efficiency is performed by setting the refractive coefficients and radiu...