Experimental and numerical studies about the effect of airflow on slider vibration with and without a disk damper

As the recording density and data transfer rate of a hard disk drive increase, TPI and rotational speed have been increased so that a single actuator alone may not be enough to control TMR budget. High-speed rotation of a disk induces airflow inside HDD cavity and the influence of airflow on HSA has become critical as TPI increases. A disk damper, which is designed to suppress the disk flutter, changes the airflow significantly so that the E-block and slider are open to the flow with relatively large pressure fluctuation. The effect of disk damper shape on the airflow field is studied numerically and experimentally from the aerodynamic point of view. Unsteady airflow in HDD cavity is simulated numerically by using a large eddy simulation method and frequency spectrum of the pressure fluctuation near the slider is obtained. Numerical results are compared with experimental results for three different-shape disk dampers and two types of E-blocks. The relationship is analyzed between the vibration of the slider and the pressure fluctuation of the airflow near the slider. A newly proposed shape of disk damper shows good characteristics on suppressing the vibration of the slider due to the airflow.