Modeling and Simulation of the Interaction between 3-D Lubricant Droplets on the Slider Surface and Air Flow within the Head/Disk Interface of Disk Drives

Abstract

In this paper, 3D modelling of the interaction between lubricant droplets on the slider surface and air flow within the head/disk interface of disk drives is presented. A very strong coupling between the lubricant droplet motion and air flow is discovered for ultra low flying slider design. The lubricant droplet is driven to migrate towards the slider's trailing edge by a net effect of air shearing, air bearing pressure gradient and disjoining pressure gradient. The droplet simultaneously undergoes significant shape deformation. The moving and deforming droplet in turn modifies the effective air bearing surface profile and induces a corresponding air flow adjustment. Our results based on the new 3-D droplet model show that the lubricant droplet and air flow interaction may induce nonnegligible air bearing force, pitch moment and slider's flying attitude change for low flying slider design.