Unsteady flow-induced vibration of the slider in a commercial hard disk drive

• Main Author: Toh, Jeffrey See Ren.
• Other Authors: Huang Xiaoyang
• Format: Final Year Project
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering::Mechanical engineering::Fluid mechanics
• Online Access: http://hdl.handle.net/10356/54105
• Institution: Nanyang Technological University

The Flow-Induced Vibration (FIV) of Head Gimbal Assembly (HGA) occurred as a result of turbulent airflow within the commercial hard disk drive HDD. Therefore, this project aims to conduct an investigation through numerical simulation to determine the characteristics of FIV of the HGA. To perform the simulation, a simplified 2-dimensional Large Eddy Simulation (LES) model was constructed, by having channel flow around a rectangular block with the use of FLUENT in ANSYS Workbench. The variation in pressure and velocity over several nodes of around the HGA was then observed by consolidating the data with the aid of MatLab. From the results obtained and analyzed in the frequency domain, high activities in pressure and x-velocity fluctuations were observed at locations directly above and beneath the HGA plate. This was due to high turbulence in these regions. The results had also shown that pressure fluctuations around the HGA plate were highly related with FIV, with principle peaks occurring at approximately 1.5 kHz, 2.8 kHz, 4.3 kHz. Similarly, principle peaks of velocity fluctuations occurred at the frequencies corresponding to those of pressure fluctuations. Based on the corresponding drag force which was calculated by having the difference of transient pressure between two nodes, it was observed that the drag force had a direct aerodynamic excitation of the FIV on the HGA plate. In conclusion, the characteristics of FIV of the HGA plate could be analysed through the studying the behaviour of pressure and x-velocity fluctuations around the HGA plate.