nqian Li

Implementation of corner-free truncation strategy in DGTD method

Abstract In this paper, the corner-free truncation (CFT) strategy for analyzing certain geometries is proposed within the framework of Discontinuous Galerkin Time Domain. The proposed algorithm used scalene ellipsoid boundary, and it is universal for any ellipsoid (sphere, spheroid, and scalene ellipsoid). The advantage of this proposed algorithm is that it allows semi-principal axes (a, b, c) that can be different. Compared with spheroid or sphere, scalene ellipsoid can be easily adjusted to match certain geometries and reduces computational cost. The accuracy and efficiency of the proposed CFT strategy is verified by numerical examples.

SO-DGTD method for dispersive media

A new method called the SO-DGTD method is proposed for solving the time-dependent Maxwells equations via the Discontinuous Galerkin Time Domain (DGTD) method with dispersive media, the Shift Operator (SO) method is used to represent the constitutive relations. This method has a universal equation for dispersive media models, i.e. the Debye model, the Drude model, the Lorentz model, the SO-DGTD method can be applied to the hybrid dispersive media model. The accuracy of the proposed method is verified by numerical examples.

2-D High-Order DGTD Method and Its Application in Analysis of Sheath Propagation Characteristics

A 2-D discontinuous Galerkin time-domain (DGTD) scheme based on high-order hierarchical basis function is presented in this paper. Combined with the shift operator method solving the electromagnetic problem of dispersive media in finite-difference time domain, the iterative formula of DGTD method in dealing with plasma media is given. On this basis, taking the example of line element radiation, the computing ability of different basis functions is compared. To study the transmission characteristics of the electromagnetic (EM) wave in sheath, the DGTD calculation models of the plasma sheath of a blunt cone at different flight heights and velocities are established using Lagrange interpolation technique based on the calculation results of COMSOL (business software). The influences of antenna position, flight altitude, and flight speed on transmission characteristics of the EM wave are discussed through calculation and analyses.

High-Order SO-DGTD Simulation of Radio Wave Propagation Through Inhomogeneous Weakly Ionized Dusty Plasma Sheath

On account of high-order hierarchical basis functions and shift operator concept, a technique of shift operator discontinuous Galerkin time domain is proposed to manage the electromagnetic problems of weakly ionized dusty plasma. Based on the numerical results of the multiphysics commercial software COMSOL and combined Lagrangian interpolation technique, the model of metallic blunt cone aircraft with weakly ionized dusty plasma sheath is established. The radio wave transmission characteristics of the sheath are analyzed under the conditions of varying speed and height of the flight.