Determination of boundary conditions in extended thermodynamics via fluctuation theory
Determination of boundary conditions in extended thermodynamics via fluctuation theory
复制标题
通过涨落理论确定扩展热力学中的边界条件
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
Na Zhao
中科院分区：
文献类型：
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作者：
Elvira Barbera;Ingo Müller;Daniel Reitebuch;Na Zhao
摘要：本文提出了一个用于计算静止稀薄气体温度场的广义热力学方程组。数值模拟表明，在这种情况下的温度场应表现出叠加在经典傅立叶解的边界层。为了从扩展的矩热力学中导出这样的场，需要更高矩的边界值，而这在实践中是无法指定和控制的。我们建议，这样的边界数据出现的平均值的热波动，从而计算它们。结果与数值模拟定性一致，定量上也是同一数量级。
Abstract.A system of equations from extended thermodynamics is proposed for the calculation of the temperature field in a rarefied gas at rest. Numerical simulations suggest that the temperature field in this case should exhibit boundary layers superposed on the classical Fourier solution. In order to derive such a field from the extended thermodynamics of moments, one needs boundary values for higher moments, which in practice cannot be assigned and controlled. We suggest that such boundary data emerge as mean values of thermal fluctuations and thus calculate them. The result agrees qualitatively with numerical simulations and it is quantitatively of the same order of magnitude.