Science and technology of polymeric ablative materials for thermal protection systems and propulsion devices: A review

The Porous-material Analysis Toolbox based on OpenFOAM is a fully portable OpenFOAM library. It is implemented to test innovative multiscale physics-based models for reacting porous materials that undergo recession. Current developments are focused on ablative materials. The ablative material response module implemented in the Porous-material Analysis Toolbox relies on an original high-fidelity ablation model. The governing equations are volume-averaged forms of the conservation equations for gas mass, gas species, solid mass, gas momentum, and total energy. It may also simply be used as a state-of-the-art ablation model when the right model options are chosen. As applications, three physical analyses are presented: 1) volume-averaged study of the oxidation of a carbon-fiber preform under dry air, 2) three-dimensional analysis of the pyrolysis gas flow in a porous ablative material sample facing an arcjet, and 3) comparison of a state-of-the-art and a high-fidelity model for the thermal and chemical respo...

Porous-Material Analysis Toolbox Based on OpenFOAM and Applications

Detailed chemical equilibrium model for porous ablative materials

Surface temperature jump beyond active oxidation of carbon/silicon carbide composites in extreme aerothermal conditions

Laminated carbon/glass fiber reinforced polymer matrix composite structures experience rapid temperature rise, resin decomposition, delamination, thermal ablation, and possible dielectric breakdown subjected to lightning strikes. The predictive analysis of these damage is challenging due to the complicated electric-thermal-mechanical-chemical coupling effects. In this paper, the basic physics, problem formulations, and numerical approaches for such multiphysics analysis are thoroughly reviewed. Limitations of the existing problem formulations and numerical approaches are extensively discussed. Possible solutions to overcome those limitations and future directions on improving the fidelity and accuracy of such predictive analysis are also provided. In addition, part of the material properties that are required for these analyses, such as the temperature-dependent thermal, electrical, and mechanical properties of the composite lamina, the fracture properties of the interface resin, and the dielectric breakdown strength of the composite laminate are collected from various sources and are provided in this paper.

Multiphysics analysis of lightning strike damage in laminated carbon/glass fiber reinforced polymer matrix composite materials: A review of problem formulation and computational modeling

*† A review of the classic techniques used to solve ablative thermal response problems is presented. The advantages and disadvantages of both the finite element and finite difference methods are described. As a first step in developing a three dimensional finite element based ablative thermal response capability, a one dimensional computer tool has been developed. The finite element method is used to discretize the governing differential equations and Galerkin’s method of weighted residuals is used to derive the element equations. A code to code comparison between the current 1-D finite element tool and the 1-D Fully Implicit Ablation and Thermal response program (FIAT), a NASA-standard finite difference tool, has been performed.

/pdf/ablative-thermal-response-analysis-using-the-finite-element-p27lwxczap.pdf

Ablative Thermal Response Analysis Using the Finite Element Method

Thermal analysis of a vehicle designed to return samples from another planet, such as the Earth Entry vehicle for the Mars Sample Return mission, presents several unique challenges. The scientific purpose of a sample return mission is to return samples to Earth for detailed investigation. The Earth Entry Vehicle (EEV) must contain the samples after they have been collected and protect them from the high heating rates of entry into the Earth''s atmosphere. This requirement necessitates inclusion of detailed thermal analysis early in the design of the vehicle. This paper will describe the challenges and solutions for a preliminary thermal analysis of an Earth Entry Vehicle. The primary challenges included accurate updates of model geometry, applying heat fluxes that change with position and time during exo-atmospheric cruise and entry, and incorporating orthotropic material properties. Many different scenarios were evaluated for the exo-atmospheric cruise to attain the desired thermal condition. The severity of the heat pulse during entry and the material response led to some unique modeling solutions. Overall, advanced modeling techniques and mathematical solutions were successfully used in predicting the thermal behavior of this complex system.

/pdf/preliminary-thermal-analysis-of-a-mars-sample-return-earth-2923bgqq8n.pdf

Preliminary Thermal Analysis of a Mars Sample Return Earth Entry Vehicle

A review of the classic techniques used to solve ablative thermal response problems is presented. The advantages and disadvantages of both the finite element and finite difference methods are described. As a first step in developing a three dimensional finite element based ablative thermal response capability, a one dimensional computer tool has been developed. The finite element method is used to discretize the governing differential equations and Galerkin's method of weighted residuals is used to derive the element equations. A code to code comparison between the current 1-D tool and the 1-D Fully Implicit Ablation and Thermal Response Program (FIAT) has been performed.

/pdf/ablative-thermal-response-analysis-using-the-finite-element-1nzah4lrau.pdf

A Dec John

Papers

Ablative Thermal Response Analysis Using the Finite Element Method

Preliminary Thermal Analysis of a Mars Sample Return Earth Entry Vehicle

Ablative Thermal Response Analysis Using the Finite Element Method