Oscillatory buoyant thermocapillary flow
Oscillatory buoyant thermocapillary flow
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振荡浮力热毛细管流
DOI：
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发表时间：
1994
期刊：
影响因子：
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通讯作者：
A. Zebib
中科院分区：
文献类型：
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作者：
M. Mundrane;A. Zebib
在Grashof数（Gr）、Reynolds数（Re）、纵横比和Prandtl数（Pr）参数空间中，对二维浮力热毛细流的特征和稳定性进行了计算研究，毛细数（Ca）为最大阶数。低Pr流体的热毛细对流的计算通常产生稳定的结果。纯浮力对流（Re=0）的计算表现出一个Hopf分叉Grcr（没有热毛细现象），这是很好理解。因此，结合热毛细浮力问题进行了研究，以调查在极限Gr→0振荡对流的开始。当Re较小时，固定Gr = Grcr时的非定常自然对流模式仅略有改变。当热毛细作用与浮力（Re = 0）一起起作用时，它是稳定的，因为在Gr = Grcr处发生向非定常流的过渡，正如严格浮力问题所定义的那样。当热毛细作用与浮力相反时（Re<0），热毛细作用对相对温度是不稳定的。
A computational study of the character and stability of two‐dimensional buoyant thermocapillary flows, valid to leading order in capillary number (Ca), is conducted in the Grashof number (Gr), Reynolds number (Re), aspect ratio, and Prandtl number (Pr) parameter space. Calculations of thermocapillary convection for low Pr fluids have generally produced steady results. Calculations of pure buoyant convection (Re=0) exhibit a Hopf bifurcation at Grcr (no thermocapillarity) that is well understood. Thus, the combined thermocapillary buoyant problem is studied to investigate the onset of oscillatory convection in the limit Gr→0. The unsteady natural convection pattern at fixed Gr≳Grcr is modified only slightly for low values of Re. When thermocapillarity acts in conjunction with buoyancy (Re≳0) it is stabilizing, in that the transition to unsteady flow occurs at Gr≳Grcr, as defined for the strictly buoyant problem. When thermocapillarity acts in opposition to buoyancy (Re<0), it is destabilizing for relativel...