Ionization equilibrium and partition functions of high-temperature weakly non-ideal Flibe gas**Much of this work has been presented at the 15th ANS Topical Meeting on the Technology of Fusion Energy (TOFE) (Washington, DC, November 2002).

Abstract

A model for the ionization equilibrium of weakly non-ideal Flibe plasma is presented in terms of a set of coupled non-linear Saha equations supplemented by electro-neutrality and conservation of nuclei. Non-ideality effects have been taken into account in terms of lowering of the ionization potentials and truncated partition functions. A simple formulation and solution strategy of the Saha equations for the single element case has been extended for application to the case of plasma mixtures and has been used to calculate the composition of partially ionized Flibe plasma over a wide range of temperatures and densities. A criterion for the validity of the assumption of local thermodynamic equilibrium is presented and applied to the result. Effects of non-ideality corrections and approximating the partition function to the statistical weight of the ground state have been quantified and presented.