回転二重円筒間を旋回する二液流体の界面の振動と混合現象（第1報，流れの可視化による二つの液体界面の基礎研究）

摘要

回転二重円筒間を旋回する流れはテイラー渦流れrn（最近ではテイラー・クエツト流れ，またはクエツrnト・テイラー流れ，ここでは簡明のため，テイラー渦rnと呼ぶ）として知られており，非線形力学系の代表的rnなモデルとして，活発に研究成果が報告されていrnる．一般的なテイラー渦における幾何学的境界rn条件は，円筒の上下端面が固定であるが，条件を拡張rnして上端を自由表面にして非対称条件としたテイラ山rn渦も研究されている．これには，Cole，の研究を始rnめ，Toyaら，Watanabeら，がある．%This work studies wave motions and mixing phenomena in an interfacial surface of two immiscible fluids between rotating cylinders, the inner cylinder is rotating and the outer cylinder is fixed. This report clarifies a series of waving and mixing phenomena by flow visualization technique. When the Reynolds number was increased, the interfacial surface became unstable due to the centrifugal force and consequently the surface swelled up around the inside wall of the outer cylinder. At last the swelled part of the surface was torn off and a droplet of a liquid penetrates into the other liquid. It was clarified that the amplitude of the swelled film of surface in axial direction was increased up to a certain value with the Reynolds number. The critical Reynolds number for the onset of the mixing was decreased with aspect ratio. However it was not depended on the ratio of the viscosities of the two-liquids.