Reducing disk flutter by improving aerodynamic design of base castings

The purpose of this paper is to present two aerodynamically designed base castings that could substantially reduce disk flutter due to turbulent excitations in high-speed disk drives. The first design includes aerodynamic brackets to smooth the shroud contour and an extended shroud to reduce the shroud opening. The second design is a Velcro treatment to modify turbulence generation. Experimental results show that smoothing the shroud corners and reducing the shroud opening can reduce disk flutter by as much as 50%. Introducing a Velcro layer to the inner surface of the shroud can perturb the boundary layer and modify turbulent excitations.