A conformal symplectic multi-resolution time-domain method with ADE-PML

In this paper, the conformal finite-difference time-domain (CFDTD) technique and the concept of effective dielectric constant are applied to symplectic multi-resolution time-domain (SMRTD) algorithm based on Daubechies scaling functions, resulting in a conformal SMRTD (C-SMRTD) method. Moreover, a novel implementation of perfect matched layer with auxiliary differential equation (ADE-PML) is presented for the SMRTD method. Numerical results of the radar cross section (RCS) of a dielectric sphere verify the effectiveness of the C-SMRTD method, which shows good agreement with the results derived by analytical methods. It is also shown that the accuracy of the C-SMRTD method has been significantly improved compared with the MRTD method with step approximation, and the proposed method has an advantage over CFDTD at saving the CPU time and memory. Furthermore, a vault-top tunnel model is established with the proposed method, and the characteristic of the field cross-section distribution of the electromagnetic pulse (EMP) propagation in the tunnel model is also presented and discussed.

Distributive Characteristics of Gas Phase in a Liquid when Bottom Blowing

This paper provides the results of research into the structure of gas flow in a plume rayed by laser in barbotage zone. The technology of steel out-of-furnace treatment facing a number of challenges necessitates a quite clear view of mechanisms of structure formation and dynamics of liquid and gas phases in an upward gas-liquid flow (in a “plume”) above the gas-feeding nozzle. Gas phase distribution, plume height and cross-section distribution and values of liquid rates determine mainly the dynamics of a melt flow in other out-of-the-plume parts of the bath.