@article{62b052e95e804537a75e82f3cd391a76,
title = "Gas–surface interactions in lightweight fibrous carbon materials",
abstract = "We investigate reactive and non-reactive scattering of hyperthermal beam of gas particles within highly porous carbon-fiber preform using particle-based numerical simulations. High-resolution X-ray tomography images of the microstructure is used to resolve its complex fiber network. The gas–surface interaction is studied at material temperatures up to 2000 K, typical of hypersonic aero-thermal environments. We extended a detailed surface chemistry model for oxidation of vitreous carbon to carbon-fiber materials. The model agrees well with experiments and predicts increasing oxidation product flux with larger porosities. Higher porosities lead to a larger fraction of thermalized argon atoms and greater mole fraction of CO for the oxygen beam due to greater penetration of the beam into the microstructure. It is found that a 6% porosity increase results in higher mole fractions of CO and lower amounts of O, with differences of around 10% of the total product flux. Furthermore, we construct an effective oxidation model with porosity-dependent rates that inherently accounts for the characteristics of the material microstructure and its varying porosity. Comparison of full microstructure simulation results and the effective model applied to a flat surface showed excellent agreement, thus suggesting that the model can be used directly in computational fluid dynamics codes.",
keywords = "Ablation, Carbon fibers, Gas–surface interaction, Oxidation, Tomography",
author = "{Swaminathan Gopalan}, Krishnan and Arnaud Borner and Ferguson, {Joseph C.} and Francesco Panerai and Mansour, {Nagi N.} and Stephani, {Kelly A.}",
note = "Funding Information: This work is supported through contract NNA15BB15C to AMA, Inc. from the Entry Systems Modeling project (Michael D. Barnhardt project manager, Aaron M. Brandis principal investigator) as part of the NASA Game Changing Development (GCD) program of NASA's Space Technology Mission Directorate. Part of this work was performed at the Stanford Nano Shared Facilities (SNSF), supported by the National Science Foundation, United States under award ECCS-1542152. KAS also acknowledges support from the NASA Space Technology Mission Directorate through the Presidential Early Career Award for Scientists and Engineers. FP is supported by the Air Force Office of Scientific Research, United States under award number FA9559-19-1-0050. The authors thank Prof. Minton and his group at MSU for providing the data and useful discussions. The authors would also like to thank F. Semeraro and Dr. M. Haw for their review of the manuscript and useful feedback. Funding Information: This work is supported through contract NNA15BB15C to AMA, Inc. from the Entry Systems Modeling project (Michael D. Barnhardt project manager, Aaron M. Brandis principal investigator) as part of the NASA Game Changing Development (GCD) program of NASA{\textquoteright}s Space Technology Mission Directorate. Part of this work was performed at the Stanford Nano Shared Facilities (SNSF), supported by the National Science Foundation, United States under award ECCS-1542152 . KAS also acknowledges support from the NASA Space Technology Mission Directorate through the Presidential Early Career Award for Scientists and Engineers. FP is supported by the Air Force Office of Scientific Research, United States under award number FA9559-19-1-0050 . The authors thank Prof. Minton and his group at MSU for providing the data and useful discussions. The authors would also like to thank F. Semeraro and Dr. M. Haw for their review of the manuscript and useful feedback. Publisher Copyright: {\textcopyright} 2022 Elsevier B.V.",
year = "2022",
month = apr,
day = "1",
doi = "10.1016/j.commatsci.2022.111190",
language = "English (US)",
volume = "205",
journal = "Computational Materials Science",
issn = "0927-0256",
publisher = "Elsevier",
}