Transport Properties of Ionized Species^a

Abstract

A universally applicable model is presented for the calculation of the transport properties of ionized species in CFD simulations. A multicomponent mixture formulation and simple mixing rules are used to compute the transport coefficients of dissociated and ionized air from room temperature up to 30000 K at different pressures. Both formulations share little input data, which simplifies the handling of the transport model. The calculated binary diffusion coefficients are similar to the results of Levin et al.1–3 and Capitelli et al.4 The computed transport coefficients of the mixture are compared to the results of Gupta et al.5 A good agreement is found in the temperature range below 10000 K. At higher temperatures the results differ, because of the differences in the collision integrals of neutral‐ion and Coulomb interactions and because of the use of higher approximations of transport properties of electrons in the present model.

Thermodynamics and transport properties of metal/inert-gas mixtures used for arc welding

“…In this paper we focus on arc welding as an industrial application. However, this study also significantly extends and improves the transport model developed earlier [1]. In earlier publications, we presented a first version of the detailed transport model [1] and its application to high-temperature air (300 K < T < 30 000 K) at different pressures.…”

“…However, this study also significantly extends and improves the transport model developed earlier [1]. In earlier publications, we presented a first version of the detailed transport model [1] and its application to high-temperature air (300 K < T < 30 000 K) at different pressures. Recent extensions included carbon dioxide and water at pressures of 0.1 mbar to 100 bar in the same temperature range [2] and the ion transport (and reactions) in lean methane flames [3].…”

“…The results are validated by comparison with transport properties from literature. However, this study also significantly extends and improves the transport model developed earlier [1,3]. The transport properties are calculated using Chapman-Enskog theory.…”

Thermochemical Nonequilibrium 2D Modeling of Nitrogen Inductively Coupled Plasma Flow

“…Because the first-order formula Eq. ( 26) was derived under the chemical equilibrium assumption [45] , and only the first-order ordinary diffusion coefficient was used in Eq. ( 26) [20] , thus, in chemical nonequilibrium or high temperature conditions the first-order formula of electrical conductivity seems apt to lose its accuracy.…”