Investigation on the Large-Scale Vortex Structures of the Complex Flow induced by Rotating Disks in a Non-Axisymmetric Enclosure

本研究的目的是澄清流动诱导振动的发病机制遇到的流动诱导的旋转盘。建立了一个实验模型，考虑到非轴对称的护罩开口和用于阅读/写入数据的臂存在于硬盘驱动器。在折射率匹配的条件下，通过流动显示研究了复杂的流动结构，其中工作流体的折射率与透明实验流动模型的折射率相吻合。特别是，研究的重点是多边形流动结构形成的大尺度涡，流动停滞在围带开口和臂尾流。其结果是，它被证实的多边形结构，可以保持即使在组合的轴对称外壳与臂插入和流动表现出强烈的三维臂插入的影响。

The present study aimed to clarify the onset mechanism of flow-induced vibration encountered at the flow induced by rotating disks. An experimental model was built taking into account of the non-axisymmetric shroud opening and the arm for reading/writing data existing in a hard disk drive. The complex flow structure was investigated through flow visualization under a matched refractive-index condition where the refractive index of the working fluid coincided with that of the transparent experimental flow model. In particular, the investigation focused at the polygonal flow structure formed by large-scale vortices, flow stagnation in the shroud opening and the arm wake. As a result, it was confirmed that the polygonal structure can be maintained even under the combination of the axisymmetric enclosure with the arm insertion and that the flow exhibits strong three-dimensionality influenced by the arm insertion.