In order to identify transitional flow, the linear stability of inward flow in a narrow gap between co-rotating disks is studied. Two methods are developed. The local approach assumes periodic nature of the flow in radial and circumferential direction, whereas the computationally more expensive biglobal variant only requires periodicity in circumferential direction. Stability maps are provided for a single set of operating conditions spanning a range of Reynolds numbers at fixed rotor geometry and rotational speed. The theoretical findings are compared to a set of experimental velocity profiles that includes the transitional region according to profile shapes. Apart from some explainable inconsistencies, the determined stability limits agree with each other and with results from previous studies.

为了识别过渡流，研究了在同向转盘之间的狭窄间隙中向内流的线性稳定性。开发了两种方法。局部方法假定流体在径向和圆周方向上具有周期性，而计算上更昂贵的双全局变量仅要求在圆周方向上具有周期性。针对在固定的转子几何形状和转速下跨越一系列雷诺数的一组运行条件提供了稳定性图。将理论发现与一组根据轮廓形状包括过渡区域的实验速度轮廓进行比较。除了一些可以解释的不一致之外，确定的稳定性极限彼此一致并且与先前研究的结果一致。