Reduction of flow-induced vibration and noise of an optical disk drive

With the increased demands in performance, the optical disk drive needs to have high speed, be more stable and less noisy. However, the disk vibration and the associate noise induced by the rotating flow caused by fluid-structure interactions become more severe as the rotating speed of the disk drive increases. The purpose of this research is to design a disk cover of an optical disk drive that can effectively improve the flow-induced disk vibration and the associate noise as the rotating speed of the disk increases. Numerical results from the finite-element analysis show that altering the shape of disk top cover influences the rotating flow and the corresponding secondary recirculating vortex, and then affects the disk vibration. With a proper design of a disk cover, the flow-induced disk vibration can be reduced substantially as compared to the original shape of the top cover at a rotating speed of 8000 rev/min. Furthermore, experimental results show that the associate noise that includes the flow noise and structure-borne noise of disk can be reduced at least 10dB at the same rotating speed. (C) 2008 Elsevier Ltd. All rights reserved.