Ablation of carbon-based heat shield materials in Jupiter-like heating conditions

In this presentation, we report on experiments utilizing the DIII-D tokamak to investigate the ablation of various carbonaceous materials and assess their feasibility for use in thermal protection systems on spacecraft traveling to Jupiter. We recorded mass loss rates for three types of samples: porous carbon, glassy carbon, and ARJ graphite for different heating conditions. Due to inherent properties of the tokamak plasma (e.g., high temperature, rotation, and fast flows), the heat flux deposited to the material samples is comparable to that experienced by the Galileo probe during its entry into Jupiter's atmosphere. Here we discuss scaling between laboratory and space conditions, specifics of the experimental design, and calculations of material ablation as a function of incident heat flux. The validity of several analytical ablation models available in the space community is tested against mass loss rates recorded in the experiments. The experimental results are further compared to a numerical model of meteor ablation adapted for entry into Jupiter's atmosphere, which allows for scaling between laboratory and space conditions.