Theoretical Analysis of Flying Characteristics for Air-Helium Filled HDD

Abstract:

This paper presents the flying characteristics of air-helium filled hard disk drive for a self-acting two rails flat slider bearing. Numerical scheme based on the finite difference with multi-grid multi-level technique were implemented for the ultra-low flying height sliders. The characteristics of air-helium filled HDD have been examined in this research work. The results shown that the change of flying height is significantly for various fraction of air-helium filled, at various operating conditions such as temperature velocity and mass of slider. Increase of velocity, flying height increase. Increase both the temperature and the mass load, flying height decrease. Increasing of fraction in helium gas, the flying height decreases rapidly for 40% to 60 % of fraction in helium filled. The flying height for air-helium filled magnetic flat slider head equal to 1.3 nm at trailing edge with mass load 12 mN and velocity 20 m/s. The spacing for helium filled hard disk drive is lower than 3 nm when compared with conventional air filled hard disk drive.

• Periodical: Advanced Materials Research (Volumes 971-973)
• Pages: 844-847
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.971-973.844
• Online since: June 2014
• Authors: Mongkol Mongkolwongrojn*, Kunchit Kuanoon
• Keywords: Finite Difference Method, Helium Filled HDD, Mean Free Path, Modified Reynolds Equation, Viscosity of Helium-Air Gas Mixture Equation

References

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