A stochastic model for high-Rayleigh-number convection
A stochastic model for high-Rayleigh-number convection
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DOI：
10.1017/s0022112004003258
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发表时间：
2005-03
影响因子：
3.7
通讯作者：
S. Wunsch;A. Kerstein
中科院分区：
文献类型：
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作者：
S. Wunsch;A. Kerstein
制定了热对流的随机一维模型并将其应用于高瑞利数对流。通过与瑞利-贝纳德池传热实验数据的比较来估计两个模型参数。在广泛的物理参数值（瑞利数的六个数量级，普朗特数的五个数量级）上获得了与实验结果的合理一致性。利用该模型，研究了对流单元核心波动的统计。与现有的实验数据取得了良好的一致性。两个不同的 p.d.f.形状被看见；一个处于低普朗特数，与实验观察相匹配，另一个处于高普朗特数，但不存在实验数据。模型结果根据产生核心波动的两种不同机制进行解释。
A stochastic one-dimensional model for thermal convection is formulated and applied to high-Rayleigh-number convection. Comparisons with experimental data for heat transfer in Rayleigh–Bénard cells are used to estimate two model parameters. Reasonable agreement with experimental results is obtained over a wide range of physical parameter values (six orders of magnitude in Rayleigh number, five orders of magnitude in Prandtl number). Using the model, the statistics of fluctuations in the core of the convection cell are studied. Good agreement with available experimental data is obtained. Two distinct p.d.f. shapes are seen; one at low Prandtl number which matches experimental observations, and another at high Prandtl number for which no experimental data exists. The model results are interpreted in terms of two distinct mechanisms for the production of core fluctuations.