Air flow around a magnetic-head-slider suspension and its effect on slider flying-height fluctuation

Flow around a Watrous-type suspension was measured using a hot-wire anemometer. Although three kinds of flow cells having characteristic frequencies are detected along the suspension span, no resonance of the suspension vibration with flow excitation having specific frequencies is observed in a uniform flow. In a rotating flow, no peak frequency component is observed, probably due to high-level upstream disturbance. Changes in the flow pattern and/or vibration of the suspension with changes in the distance between a flat plate and the flange edges of the suspension, changes in disk speed, and changes in distance between the disk and the suspension are investigated experimentally. The results suggest that not a periodic excitation but an irregular one due to separations, especially at the upper leading edge and the lower trailing edge, has a significant effect on the vibration. This is confirmed by reduction in flying-height fluctuation due to flow excitation of an aerofoil section suspension whose trailing edge is made as thin as possible and where the upper leading-edge separation reattaches before the trailing edge