Mutation++: MUlticomponent Thermodynamic And Transport properties for IONized gases in C++

Ionization and dissociation effects on boundary-layer stability

“…Thermal properties of the molecular species considered in this work. Obtained from the mutation ++ database (see Magin & Degrez 2004;Scoggins & Magin 2014;Scoggins 2017), which gathers values originally in Gurvich et al (1989). The degeneracies and activation temperatures of the various electronic energy levels considered were also obtained from the mutation ++ database, and are collected in Miró Miró et al (2018a) and Miró Miró (2020).…”

“…For all other flow assumptions, one must approximate the nonlinear functional dependency of the vibrational and electronic energy modes on temperature. Such expressions are obtained from differentiating the partition functions of the different energy modes assuming molecules behave like a rigid rotor and a harmonic oscillator, and assuming species to populate the electronic energy levels according to a Boltzmann distribution (see Scoggins & Magin 2014;Scoggins 2017;Anderson 2006):…”

“…Equation (A 17a) corresponds to the volumetric partition function of the translational energy, since it has been divided by the system's volume. The expression for the partition function of the electron species' internal energy Q Int e − (A 17e) is formulated to account for the contribution of the spin of the free electron to the species entropy (see Scoggins & Magin 2014;Scoggins 2017). Note that the expression of the electronic partition function (A 17d) features a summation between zero and the number of electronic modes.…”

Blackout analysis of Mars entry missions

“…This work utilizes the Mutation library (multicomponent thermodynamic and transport properties for ionized gases in C), which is a modern electronic database/library developed at the von Karman Institute and specifically designed to provide efficient algorithms for obtaining thermodynamic and transport properties of non-equilibrium mixtures (Magin 2004). For evaluating species thermodynamic properties, the library can perform a direct evaluation of the species partition function or perform an explicit evaluation of thermodynamic functions from a given set of polynomials (Scoggins et al 2020). In particular, Mutation incorporates the Martian atmospheric modelling data that has been collected in the works of Gurvich et al.…”

Decoupling ablation effects on boundary-layer stability and transition

“…For all other flow assumptions, one must approximate the nonlinear functional dependency of the vibrational and electronic energy modes on temperature. Such expressions are obtained from differentiating the partition functions of the different energy modes assuming molecules behave like a RRHO, and assuming species to populate the electronic energy levels according to a Boltzmann distribution (see Scoggins & Magin 2014;Scoggins 2017;Anderson 2006):…”