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NASA NTRS · 20240013889

Updates to PATO’s Thermo-Mechanical Model

Abstract

The solid mechanics module within the Porous material Analysis Toolbox (PATO) material response code was updated to model the stress contribution from both internal pressure and pyrolysis shrinkage as function of material’s decomposition. Incorporating these physical phenomena, alongside the previously included temperature dependent mechanical properties, thermal expansion, and aerodynamic loads, allows for a more accurate thermo-mechanical behavior modeling of Thermal Protection System (TPS) materials, which is critical to assess spallation risks during atmospheric entry. This poster outlines the workflow for obtaining the necessary PATO inputs, derived from dilatometry experiments, which are used to model the stress field in TPS materials due to thermal expansion and pyrolysis shrinkage. Furthermore, to analyze the relevance of the stress contribution from the internal pressure, a study was conducted using TACOT with different permeability values.

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Sergio Fraile Izquierdo, Jeremie B E Meurisse, Justin B Haskins, Nagi N Mansour. Updates to PATO’s Thermo-Mechanical Model. https://ntrs.nasa.gov/citations/20240013889

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