Transport Phenomena in Thermal Engineering. Volume 2

ISBN Print: 1-56700-015-0

THERMODYNAMIC AND TRANSPORT PROPERTIES OF NON-EQUILIBRIUM PLASMA

DOI: 10.1615/ISTP-VI.1190
pages 1504-1509

Resumo

For nonequilibrium plasma, thermodynamic and transport properties could be obtained by numerical methods. A multi-temperature thermodynamic model was introduced to quantify the properties of the nonequilibrium plasma. Equations for multi-temperature chemical compositions were derived by chemical affinity approaches. The multi-temperature model is based on generalized multi-thermal equilibrium model, in which it is assumed that a thermodynamic system is composed of sub-systems of its own temperature. The thermodynamic properties are dependent on the pressure and the temperatures. Especially, Debye-Huckel approximation is important for chemical compositions and thermodynamic properties. In this presentation, the Debye-Huckel corrections for the multi-temperature plasma are presented and their effects to the lowering of the ionization energy are discussed. Using the Debye-Huckel approximation, the properties of hydrogen plasma are evaluated for various nonequilibrium conditions. The effects of kinetic nonequilibrium and excitational nonequilibrium are summarized and the nonequilibrium transport properties are presented. Thermal conductivity, electrical conductivity, diffusion coefficient and viscosity for nonequilibrium conditions are included in the transport properties. The kinetic nonequilibrium effects to the viscosity, diffusion coefficient and thermal conductivity are significant. It was found that the excitational nonequilibrium effects are important for the nonequilibrium diagnostic methods. Without considering excitational nonequilibrium effects, the evaluated properties of the plasma could be different from the correct value upto orders of magnitude.