As one of the important aerodynamic problems of magnetic disk drives for microcomputers, a flow between shrouded corotating disks and its instability have been investigated. The four-decker circular disk pack is enclosed in a cylindrical container to endure the axial symmetry. Mean and fluctuating velocity fields induced by the disk rotation has been obtained by employing fine scale multi-sensor hot-wire probes. First, the velocity distributions of 2D axisymmetric base flow field are reported. The occurrence of 3D non-axisymmetric flow will then be discussed, where the rotational speed as well as the number of cells will be discussed and compared with the existing data.
