Numerical Simulations of the Head-Disk Interface in Hard Disk Drives

This monograph is based on the Doctoral thesis of theauthor at the University of California Berkeley(2008). Over the past few years hard disk drives(HDD) have become viable for many consumer productsthat require large storage capacities. Theseapplications subject the HDD to adverse conditionswherein the reliability and performance of the drivebecomes critical. This book presents a Finite Elementbased simulation methodology which is used to studydynamic events such as load/unload and shock of the HDD.The dynamics of the HDI are governed by thestructural components of the HDD as well as theair-bearing which is formed between the spinning diskand the flying head. A new numerical scheme ispresented to solve the resulting nonlinear coupledset of equations using stabilized finite elementsfirst for the steady state case and then for the timedependent case. Meshing/refinement strategies areexplored in order to obtain accurate results with asfew degrees of freedom as possible. Finally themethodology is applied to simulate the shock andload/unload processes in HDDs and carry outparametric studies on the performance of a 1 HDD.