Spectroscopy Measurements on Ablation Testing in High Enthalpy Plasma Flows

摘要

The objective of this work is to develop the capability of testing and characterization of ablative materials exposed to high enthalpy plasma flows including both classical and spectroscopic based measurement techniques. Two different ablative material specimens, a newly developed carbon resin composite ablator (MONA, Lockheed Martin) and a cork compound (AMORIM Cork composites), were selected to perform the measurements. A comprehensive setup of measurement techniques was applied to the Plasmatron facility (chapter 3) to determine and characterize temperature evolution inside and at the surface of the sample as well as the recession rate. Further, the chemical composition of the freestream and the surrounding gas layer in front of the sample during the ablation process was determined using emission spectroscopy. The obtained results are presented in chapter 5, which depicts the degradation of the samples due to ablation (mass loss & surface recession), different temperature measurements (surface & inside) and spectroscopic results (freestream & ablation). A final conclusion of the whole test campaign is made in chapter 6 summarizing the results obtained.