• aerothermodynamics
• cfd
• hydrogen ionization
• hypersonic
• ice giant
• Neptune
• non equilibrium simulations
• radiative heating

This study performs a CFD aerothermodynamic analysis along the stagnation line of the flow during an aerocapture maneuver in Neptune at 29 km/s. Thermodynamics, transport, and kinetics properties were updated using the work by CNR ISTP Bari and implemented in the VKI Mutation++ library. Reactive, non-equilibrium solutions are computed for 6 different cases to analyze the impact of ionization, the presence of carbon species, and different gas-surface interactions on the flow. Notably, an updated ionization kinetics model is applied, resulting in a higher concentration of ions in the shock layer and bringing the results closer to experimental values. Then, we computed the radiative transfer using NEQAIR for each solution. The study proves the relevance of ablation with a worst-case scenario of 1.7 kW⁄cm2 for the convective heat flux and 2.6 kW/cm2 for the radiative heat flux at the stagnation point.