Efficient methodology for analyzing head disk interface with application to unloading process

Abstract

Head disk interfaces (HDI) and Load/Unload (L/UL) processes have been studied numerically for over a decade. Several simplified and comprehensive models have been developed to study the HDI in L/UL processes. All existing methods simulated the L/UL behaviors of a slider by iteratively obtaining the instantaneous attitude of a slider through repeatedly solving a modified Reynolds equation which is coupled with the dynamics of the suspension. Despite its relative accuracy, this approach requires huge amount of computational time and power. Hence, developing a simple and efficient model, which is capable of modeling the behavior of the head-disk interface during the L/UL processes, is desired and critical to aid the design process of slide/suspension systems. NOMENCLATURE OF VARIABLES AND SYMBOLS XVI F p total air bearing positive force F n total air bearing negative force P p positive air bearing pressure at the grid points P n negative air bearing pressure at the grid points M p total positive moment M n total negative moment M pp positive moment caused right-hand side positive force M pn positive moment caused left-hand side negative force M np negative moment caused left-hand side positive force M nn negative moment caused right-hand side negative force a, b, c, d variable coefficients changing with θ m, n constants for a slider adjusting the curvature of the fitting f, u, w, v moments curve fitting coefficients