Conditions for supersonic bent Marshak waves
Abstract
Supersonic radiation diffusion approximation is an useful method to study the radiation transportation. Considering the 2d Marshak theory, and an invariable source temperature, conditions for supersonic radiation diffusion are proved to be coincident with that for radiant flux domination in the early time when √(ε)x{sub f}/L≪1. However, they are even tighter than conditions for radiant flux domination in the late time when √(ε)x{sub f}/L≫1, and can be expressed as M>4(1+ε/3)/3 and τ>1. A large Mach number requires the high temperature, while the large optical depth requires the low temperature. Only when the source temperature is in a proper region the supersonic diffusion conditions can be satisfied. Assuming a powerlow (in temperature and density) opacity and internal energy, for a given density, the supersonic diffusion regions are given theoretically. The 2d Marshak theory is proved to be able to bound the supersonic diffusion conditions in both high and low temperature regions, however, the 1d theory only bounds it in low temperature region. Taking SiO{sub 2} and the Au, for example, these supersonic regions are shown numerically.
 Authors:
 Key Laboratory of Pulsed Power, Institute of Fluid Physics, CAEP, P. O. Box 919108, Mianyang 621999 (China)
 Publication Date:
 OSTI Identifier:
 22408249
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physics of Plasmas; Journal Volume: 22; Journal Issue: 3; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 36 MATERIALS SCIENCE; 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; DIFFUSION; ENERGY DENSITY; GOLD; MACH NUMBER; SILICON OXIDES; SUPERSONIC FLOW; TEMPERATURE RANGE 00650273 K; TEMPERATURE RANGE 04001000 K
Citation Formats
Xu, Qiang, Email: xuqiangxu@pku.edu.cn, Ren, Xiaodong, Li, Jing, Dan, Jiakun, Wang, Kunlun, and Zhou, Shaotong. Conditions for supersonic bent Marshak waves. United States: N. p., 2015.
Web. doi:10.1063/1.4916502.
Xu, Qiang, Email: xuqiangxu@pku.edu.cn, Ren, Xiaodong, Li, Jing, Dan, Jiakun, Wang, Kunlun, & Zhou, Shaotong. Conditions for supersonic bent Marshak waves. United States. doi:10.1063/1.4916502.
Xu, Qiang, Email: xuqiangxu@pku.edu.cn, Ren, Xiaodong, Li, Jing, Dan, Jiakun, Wang, Kunlun, and Zhou, Shaotong. 2015.
"Conditions for supersonic bent Marshak waves". United States.
doi:10.1063/1.4916502.
@article{osti_22408249,
title = {Conditions for supersonic bent Marshak waves},
author = {Xu, Qiang, Email: xuqiangxu@pku.edu.cn and Ren, Xiaodong and Li, Jing and Dan, Jiakun and Wang, Kunlun and Zhou, Shaotong},
abstractNote = {Supersonic radiation diffusion approximation is an useful method to study the radiation transportation. Considering the 2d Marshak theory, and an invariable source temperature, conditions for supersonic radiation diffusion are proved to be coincident with that for radiant flux domination in the early time when √(ε)x{sub f}/L≪1. However, they are even tighter than conditions for radiant flux domination in the late time when √(ε)x{sub f}/L≫1, and can be expressed as M>4(1+ε/3)/3 and τ>1. A large Mach number requires the high temperature, while the large optical depth requires the low temperature. Only when the source temperature is in a proper region the supersonic diffusion conditions can be satisfied. Assuming a powerlow (in temperature and density) opacity and internal energy, for a given density, the supersonic diffusion regions are given theoretically. The 2d Marshak theory is proved to be able to bound the supersonic diffusion conditions in both high and low temperature regions, however, the 1d theory only bounds it in low temperature region. Taking SiO{sub 2} and the Au, for example, these supersonic regions are shown numerically.},
doi = {10.1063/1.4916502},
journal = {Physics of Plasmas},
number = 3,
volume = 22,
place = {United States},
year = 2015,
month = 3
}

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