Abstract
We study the internal flow of Hard Disk Drives (HDDs). The flow induced by a stack of rotating disks exhibits complex behavior, which is supposed to be responsible for the performance and reliability of HDDs. We built a HDD model consisting of non-axisymmetric enclosure equipped with arms and a shroud opening. Flow visualization was performed using a scaled experimental model with all the parts made of a transparent material. An application of refractive index matching to the working fluid enabled clear view of the whole flow field with minimum optical disturbances. Velocity fields in planes parallel to the disk surfaces were evaluated using particle image velocimetry (PIV) at a Reynolds number corresponding to a typical operating condition. We focus on the flow behavior near the arms and in the shroud opening, influenced by the insertion angles of the arms.
