Pattern formation of Rayleigh-Bénard convection of cold water near its density maximum in a vertical cylindrical container.
Pattern formation of Rayleigh-Bénard convection of cold water near its density maximum in a vertical cylindrical container.
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DOI：
10.1103/physreve.86.046323
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发表时间：
2012-10
期刊：
影响因子：
--
通讯作者：
You-Rong Li;Y. Ouyang;Yupeng Hu
中科院分区：
文献类型：
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作者：
You-Rong Li;Y. Ouyang;Yupeng Hu
为了解立式圆柱形容器内冷水在密度极大值附近浮力驱动对流的对流不稳定性和多种稳定对流模式，进行了一系列三维数值模拟。容器的长径比为2，冷水的普朗特数为11.57。侧壁被认为是完全绝热的，密度反转参数固定为0.3。结果表明，冷水中的密度反转现象对对流开始的临界瑞利数和较高瑞利数时的斑图形成有重要影响。当瑞利数从3×10(3)到1.2×10(5)变化时，在不同的初始条件下得到了8种稳定、稳定的对流型。在瑞利数的某些特定范围内，还观察到多种稳定定常流型共存。
In order to understand the onset of convective instability and multiple stable convection patterns of buoyancy-driven convection of cold water near its density maximum in a vertical cylindrical container heated from below, a series of three-dimensional numerical simulations were performed. The aspect ratio of the container was 2 and Prandtl number of cold water was 11.57. The sidewall was considered to be perfectly adiabatic, and the density inversion parameter was fixed at 0.3. The result shows that the density inversion phenomenon in cold water has an important effect on the critical Rayleigh number for the onset of convection and the pattern formation at higher Rayleigh numbers. When the Rayleigh number varies from 3×10(3) to 1.2×10(5), eight stable, steady convection patterns are obtained under different initial conditions. The coexistence of multiple stable steady flow patterns is also observed within some specific ranges of the Rayleigh number.