Effect of disk surface asperity on statistic characteristics of air bearing films at the head/disk interface

As the spacing between the flying head/slider and the rotating disk in hard disk drives (HDDs) continues to decrease, some asperities on disk surface may lead to contacts and collisions between the magnetic head and disk, generating friction and wear which would then damage the working stability of HDD system. To investigate effect of disk surface asperity on static characteristics of air bearing films at the head/disk interface (HDI), Reynolds equation based on a linearized flow rate (LFR) model is solved by using a mesh-less method. The effects of asperity size and its location, the disk's rotating speed, the boundary pressure on the static characteristics of air bearing films are investigated. Numerical results show that the asperity's location on the disk surface has obvious effect on the pressure distribution of the air bearing film and its load carrying capacity.