Stability of double-diffusive convection induced by selective absorption of radiation in a fluid layer
Stability of double-diffusive convection induced by selective absorption of radiation in a fluid layer
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DOI：
10.1007/s00161-012-0234-0
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发表时间：
2012-02
影响因子：
2.6
通讯作者：
Thomas J. Wicks;A. A. Hill-A.
中科院分区：
文献类型：
--
作者：
Thomas J. Wicks;A. A. Hill-A.
对具有基于浓度的内热源的流体层进行了线性和非线性稳定性分析。清楚的双峰行为的中性曲线（固定和振荡模式）中观察到的振荡对流，这是一个以前未观察到的现象，在辐射诱导对流的发病区域。线性不稳定性分析的数值结果表明，当γ>γc时，振荡对流被抑制，γ c是内热源强度的一个临界值。线性不稳定性分析的影响，改变盐浓度的比例在上，下边界的结论是，该比例有一个显着的影响稳定边界。使用能量方法的非线性分析证实，当γ使得线性理论预测大多数静止对流的开始时，线性理论最准确地描述稳定性边界。然而，线性和非线性稳定性阈值之间的协议恶化的溶质瑞利数的任何值的值。
Linear and nonlinear stability analyses were performed on a fluid layer with a concentration-based internal heat source. Clear bimodal behaviour in the neutral curve (with stationary and oscillatory modes) is observed in the region of the onset of oscillatory convection, which is a previously unobserved phenomenon in radiation-induced convection. The numerical results for the linear instability analysis suggest a critical valueγcofγ, a measure for the strength of the internal heat source, for which oscillatory convection is inhibited whenγ>γc. Linear instability analyses on the effect of varying the ratio of the salt concentrations at the upper and lower boundaries conclude that the ratio has a significant effect on the stability boundary. A nonlinear analysis using an energy approach confirms that the linear theory describes the stability boundary most accurately whenγis such that the linear theory predicts the onset of mostly stationary convection. Nevertheless, the agreement between the linear and nonlinear stability thresholds deteriorates for larger values of the solute Rayleigh number for any value ofγ.