Computation of state to state transport coefficients using ab initio potential energy surfaces for the o + o₂ system

This work presents the quantification of transport coefficients in a state-based framework for non-equilibrium flows encountered in hypersonic re-entry applications. Vibrational state-to-state (StS) collisional properties, namely the potentials, scattering angles, transport cross-sections and collision integrals are computed for the O + O₂ system based on the recent set of nine potential energy surfaces (PESs) proposed by Varga et al.² The collision integrals are then compared with those obtained from the single Varandas and Pais PES.¹ Averaged collision integrals, based on all nine Varga et al. surfaces are then used to compute state-based transport coefficients-viscosity and thermal conductivity. A chemically frozen, non-equilibrium relaxation, and chemical equilibrium conditions are chosen to study the influence of vibrational state of O₂ on transport properties. The vibrational excitation of the molecule was found to affect the viscosity and thermal conductivity in all three cases considered.