Numerical simulation of slider air bearings based on a mesh-free method for HDD applications

This paper focuses on the development of a computational method to be used as a tool for air bearing simulation and design in modern hard disk drive. A data density of 100 Gb/in.2 has already been achieved in today’s production. The hard disk drive industry’s next goal is to increase the data density to 1 Tb/in.2 . New features in air bearing designs include shaped rails, multiple etching depths and negative pressure pockets. Thus, mesh generation is a difficult task in the air bearing simulation. This, in turn, demands the development of an accurate and easy-to-use computational method to solve Reynolds equations based on various flow models. Least square finite difference scheme, one of mesh-less methods, is presented to solve the slider air bearing problems of hard disk drives. For each specified attitude, the air bearing pressure is obtained by solving the Reynolds equation using the mesh-free method. The discretized nonlinear systems of equations are solved by successive over-relaxation (SOR) implementation, and the results of the numerical solutions are compared with other numerical and experimental data.

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