Analysis of Rarefied Effects of a Nano-scale Magnetic Head/Disk

作     者：WANG Yazhen GYIMAH Glenn Kwabena HUANG Ping 

作者机构：School of Mechanical andAutomobile Engineering South China University of Technology Guangzhou 510640 China Guangdong College of Industry and Commerce Guangzhou 510640 China 

出 版 物：《Chinese Journal of Mechanical Engineering》 (中国机械工程学报（英文版）)

年 卷 期：2009年第22卷第3期

页      面：336-340页

核心收录：

学科分类：07[理学] 0817[工学-化学工程与技术] 08[工学] 0807[工学-动力工程及工程热物理] 080203[工学-机械设计及理论] 0802[工学-机械工程] 0811[工学-控制科学与工程] 0801[工学-力学（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：supported by National Basic Research and Development Program of China (973 Program  Grant No. 2003CB716205) 

主　　题：rarefied region rarefied effect magnetic head/disk 

摘      要：When the decrease in the space between magnetic head and disk arrived at 10 nm or less, which is much lower than the mean free path of gas molecules, the gas flow presents distinctive features against the macro features because of the rarefied effects. The modified Reynolds equation considering rarefied gas effect is used to calculate the rarefied region of a negative pressure magnetic head working in the distance of 10 nm. Inverse Knudsen number was adopted to calculating the ratio of the rarefied area. According to the numerical resuks, discussions and analyses are then presented to reveal the rarefied effect on the working performances of a magnetic head. The results show that the magnetic head works in the slip-flow and transition regions and moves to the transition region with the increase in velocity. Furthermore, the maximum rarefied effects occur at the side edges where the flying height is thinner and pressure is lower, rather than in the minimum flying height on the rear. The results also show that with considering the rarefied effects, the load-carrying capacity of the magnetic head and the maximum pressure decrease significantly, but the minimum pressure slightly changes.