Modeling of non-equilibrium spherical microwave discharge

A model of a non-equilibrium spherical microwave discharge is presented. Numerical experiments are carried out for the discharge in argon at atmospheric pressure. Results are presented the characteristics of the discharge depending on external parameters (the power and frequency of the applied electromagnetic field and the size of the discharge chamber)

Flow modelling and gas heating inside a profiling channel of an electric arc plasma torch

This paper presents a theor. model for the numerical anal. of the acceleration and heating of a gas by an elec. arc in a profiling channel with a diffuser anode. The thermal parameters and transport coeffs. of helium were detd. and the approximative expression for their calcn. in a broad range of temp. (0,3-100) kK and pressures are proposed. The calcn. and study of the effect of the thermal nonequil. plasma on the characteristics of the cylindrical arc were carried out. The results of the calcns. were compared with exptl. data and calcns. obtained from an equil. plasma model. [on SciFinder (R)

Terahertz-to-infrared converter based on the polyvinylchloride matrix with embedded gold nanoparticles

Abstract Prospects for the development of devices for visualizing terahertz (THz) radiation sources can be associated with the use of the results of old studies (1965–1978) on the absorption of THz radiation by metal nanoparticles. This “renaissance” demonstrates that metallic nanoparticles can be used as nanotransducers of invisible THz radiation to infrared (IR) radiation detectable by a commercial IR camera. The investigated THz-to-IR converters are matrices that are transparent both in the THz radiation range to be visualized and in the operating range of the IR camera; matrices contain embedded metal nanoparticles. The latter, when irradiated with THz rays, convert the energy of THz photons into heat and become nanosources of IR radiation for the IR camera. In metal nanoparticles, the mechanisms of absorption of THz radiation and its conversion into heat are realized through dissipation of the energy of THz photons due to multiple scattering of electrons, as well as because of excitation of two types of phonons (transverse and longitudinal ones). The conversion of THz energy into the energy of transverse phonons occurs directly, while dissipation and excitation of longitudinal phonons occurs indirectly, through the excitation of Fermi electrons. Polyvinylchloride (PVC) was chosen as the matrix material, and gold nanoparticles were chosen as nanoparticles-fillers