论文标题
吉尔在夹心的多孔板上的问题
Gill's problem in a sandwiched porous slab
论文作者
论文摘要
经典g的稳定性问题是垂直的多孔平板中的固定和平行浮力流，并以不同的视角重新考虑了在不同温度下保持不可渗透和等温边界的稳定性问题。研究了三层平板，而不是吉尔问题中的同质平板。这三层具有对称配置，其中两个外层具有较高的导热率，而核心层的电导率要低得多。建立了一个简化的模型，其中将外层和内部芯之间的热导率比为无限。结果表明，夹层多孔平板中的流动不稳，可能会出现足够大的雷利数。还证明，这种不稳定性与以前对具有可渗透边界的多孔层的分析相吻合，考虑到外部层的渗透性比核心层的渗透性大得多的限制情况。
The classical Gill's stability problem for the stationary and parallel buoyant flow in a vertical porous slab with impermeable and isothermal boundaries kept at different temperatures is reconsidered in a different perspective. A three-layer slab is studied instead of a homogeneous slab as in Gill's problem. The three layers have a symmetric configuration where the two external layers have a high thermal conductivity, while the core layer has a much lower conductivity. A simplified model is set up where the thermal conductivity ratio between the external layers and the internal core is assumed as infinite. It is shown that a flow instability in the sandwiched porous slab may arise with a sufficiently large Rayleigh number. It is also demonstrated that this instability coincides with that predicted in a previous analysis for a homogeneous porous layer with permeable boundaries, by considering the limiting case where the permeability of the external layers is much larger than that of the core layer.
