Author ORCID Identifier
https://orcid.org/0000-0002-7102-8057
Date Available
8-28-2024
Year of Publication
2024
Degree Name
Doctor of Philosophy (PhD)
Document Type
Doctoral Dissertation
College
Engineering
Department/School/Program
Engineering
First Advisor
Dr. Alexandre Martin
Second Advisor
Dr. Sean Bailey
Abstract
Thermal protection systems are critical for protecting spacecraft from the large amounts of heating incurred during atmospheric entry. Ablative thermal protection systems in particular often consist of a carbon fiber matrix impregnated with a polymer resin and use thermal and chemical reactions to decompose the material. Weakening of these carbon fibers by oxidation, along with the impact of shear forces, results in the mechanical failure of these materials in a process known as spallation. Being able to quantify and characterize this process is important for modeling and designing heat shield materials that account for the additional spalled mass loss.
Two arc-jet campaigns conducted in the Hypersonic Materials Environmental Test System (HyMETS) and Aerodynamic Heating Facility (AHF) allowed for investigation of the spallation process through test factor comparison, high-speed imagery, and physical particle capture. The resulting analysis can be utilized to better understand the formation of spalled particles and further quantify their size and number. This will allow the total mass loss due to the spallation phenomenon to be better accounted for in models of thermal protection system materials, improving confidence in the success and reducing the cost of heat shield designs.
Digital Object Identifier (DOI)
https://doi.org/10.13023/etd.2024.335
Funding Information
This work was supported by a NASA Space Technology Graduate Research Opportunities Award (80NSCC21K1255) from 2021-2024. Additional support was provided by NASA Kentucky Graduate Fellowship award numbers 80NSSC20M0047 from 2020-2021 and NNX15AR69H from 2019-2020, as well as by NASA Kentucky EPSCoR Award number NNX13AN04A from 2013-2017. Additional support was provided by a Lexmark Fellowship in 2021. A particular thank you goes to the Entry Systems Modeling Project, who provided the arc-jet days in the Aerodynamic Heating Facility as an integral part of this work.
Recommended Citation
Price, Kristen, "Characterization of the Spallation Phenomenon in Ablative Thermal Protection System Materials Resulting from Arc-Jet Experiments" (2024). Theses and Dissertations--Mechanical Engineering. 224.
https://uknowledge.uky.edu/me_etds/224
