Validation of a Multi-solver Coupled Framework by Means of Radiation Prediction in an Inductively Coupled Plasma Wind Tunnel*

This work aims to validate a multi-solver coupled framework developed at the Center for Hypersonics and Entry Systems Studies (CHESS) by predicting radiation response measured in an inductively coupled plasma wind tunnel, Plasmatron X. The developed framework has been designed to enable simulating a wide range of operating conditions of the facility with consideration over (i) reactive hydrodynamics, (ii) electromagnetics, (iii) radiation, and (iv) material response. Multiple stand-alone computational solvers have been coupled in a scalable way while conserving their own capability. The radiation prediction is then carried out for both supersonic and subsonic plasma jet conditions to compare radiative intensity profiles for both spatially and spectrally resolved with absolute magnitude. At the supersonic jet condition in which influences of flow-radiation coupling and species electronic non-Boltzmann population distributions are significant, the shock structure over the measured intensity profiles is well reproduced by the present multi-solver coupled approach. At the subsonic jet condition, the monotonic decay of the measured intensity after the nozzle exit is successfully characterized with the reasonable agreement in absolute intensity distributions. In the low-pressure case, the amount of molecular dissociation is slightly overpredicted, implying further improvement on the framework is required. Albeit, the constructed approach is well validated via the present study.