TY - JOUR
T1 - Nonequilibrium flow through porous thermal protection materials, Part I
T2 - Numerical methods
AU - Stern, Eric C.
AU - Poovathingal, Savio
AU - Nompelis, Ioannis
AU - Schwartzentruber, Thomas E.
AU - Candler, Graham V.
N1 - Publisher Copyright:
© 2017 Elsevier Inc.
PY - 2019/3/1
Y1 - 2019/3/1
N2 - Numerical methods are developed to simulate high temperature gas flow and coupled surface reactions, relevant to porous thermal protection systems used by hypersonic vehicles. Due to the non-continuum nature of these flows, the direct simulation Monte Carlo (DSMC) method is used, and the computational complexity of the simulations presents a number of unique challenges. Strategies for parallel partitioning, interprocessor communication, complex microstructure geometry representation, cutcell procedures, and parallel file input/output are presented and tested. Algorithms and data structures are developed for a microstructure generation tool called FiberGen that enables realistic microstructures to be constructed based on targeted fiber radius, orientation, and overall porosity, with user defined variations about these values. The data structures and algorithms associated with FiberGen are robust and efficient enough to enable DSMC simulations where the microstructure geometry changes to directly simulate ablation problems. Subsonic boundary conditions are described and validated, and a number of example solutions are presented. The example problems demonstrate the difference between surface ablation and in-depth volume ablation regimes for porous TPS materials.
AB - Numerical methods are developed to simulate high temperature gas flow and coupled surface reactions, relevant to porous thermal protection systems used by hypersonic vehicles. Due to the non-continuum nature of these flows, the direct simulation Monte Carlo (DSMC) method is used, and the computational complexity of the simulations presents a number of unique challenges. Strategies for parallel partitioning, interprocessor communication, complex microstructure geometry representation, cutcell procedures, and parallel file input/output are presented and tested. Algorithms and data structures are developed for a microstructure generation tool called FiberGen that enables realistic microstructures to be constructed based on targeted fiber radius, orientation, and overall porosity, with user defined variations about these values. The data structures and algorithms associated with FiberGen are robust and efficient enough to enable DSMC simulations where the microstructure geometry changes to directly simulate ablation problems. Subsonic boundary conditions are described and validated, and a number of example solutions are presented. The example problems demonstrate the difference between surface ablation and in-depth volume ablation regimes for porous TPS materials.
KW - Ablation
KW - Numerical simulation
KW - Porous media
KW - Rarefied flow
KW - Thermal protection systems
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U2 - 10.1016/j.jcp.2017.09.011
DO - 10.1016/j.jcp.2017.09.011
M3 - Article
AN - SCOPUS:85037041715
SN - 0021-9991
VL - 380
SP - 408
EP - 426
JO - Journal of Computational Physics
JF - Journal of Computational Physics
ER -