Computational Models and Stochastic Model Updating for the Design and Development of Recording Heads

Friday, March 23, 2012 - 2:25pm - 3:25pm
Lind 305
Ajaykumar Rajasekharan (Seagate Technology)
The hard disk drive industry is replete with mathematical applications. Design and manufacturing of recording heads relies on applied mathematical applications ranging from fundamental derivation of governing equations, development of efficient numerical techniques to obtain accurate solutions, optimization algorithms for fine tuning design features and analyzing of manufacturing data (to name a few). These tasks derive knowledge from various branches of mathematics like differential equations, linear algebra, applied probability, signal processing etc.

This first part of the presentation will give an overview of computational models developed to perform coupled multi-physics simulations of the slider air-bearing suspension system. This would include the numerical methods employed to obtain various fluid and thermal solutions, surrogate models for efficient faster computation and sensitivity analysis procedures for shape optimization. The second part of the presentation addresses the problem of characterizing uncertainty using these models to predict variation in experimental results. Stochastic collocation and standard Latin-Hypercube sampling procedures are compared. Experimental results are then used to update the unknowns in the model through a Bayesian updating procedure and hence obtain a predictive computational model. Potential problems with these methods and additional applications will be discussed.

Dr. Rajasekharan graduated with a PhD in Mechanical Engineering and an MS in Financial Mathematics from Stanford University in 2008 and since then has been working as a Staff Development Engineer in the Mechanical R&D division of Seagate Technology. His primary research has been in the area of Computational Mathematics and its applications in Fluid Dynamics as well as Finance. At Seagate Dr. Rajasekharan's work has focused on developing physical models and numerical methods to understand and enable mechanical aspects of magnetic disc recording