基于多物理场的TFC磁头热传导机理及其影响因素仿真研究

为了利用微尺度热效应的热致飞高控制(TFC)磁头技术实现磁头飞行高度的精确控制,分析了工作状态下TFC滑块在多物理场综合作用下所呈现出来的传热特性及其主要影响因素,考虑了磁头磁盘间超薄气膜的稀薄效应,建立滑块导热、空气轴承表面传热、气膜流动等模型,利用有限元法,对磁头热变形作用机理及热传导特性对滑块动力学特性影响进行了仿真研究,结果表明,建立的传热模型及对雷诺方程的修正适用于求解磁头磁盘界面气膜传热问题和磁头滑块的动力学问题;影响滑块热力学性能的因素主要可以归结为加热器高度、热生成率以及材料的传热系数;空气轴承力及工作表面热变形的双重作用决定了滑块飞行高度的改变.仿真结果为磁头滑块加热器的设计及空气轴承动力学特性分析提供了依据.

Multiphysics-based simulation on heat conduction mechanism of TFC head and its influencing factors

In order to precisely control the flying height of TFC head with consideration of microscale thermal effect, the thermal conducting characteristics and the influencing factors on TFC slider which is in an operation and multi-physics field condition were analyzed. In consideration of rarefaction effect of ultra-thin film at the head/disk interface, the models of slider heat conduction, air bearing surface heat transfer, and gas flow were established; the thermal deformation mechanism and the effect of thermal conduction on dynamic characteristics of slider were analyzed by using finite element method. Results show that the thermal conducting model and the proposed modification of Reynolds equation in this study are suitable for solving the problems of thermal deformation and dynamic characteristics of head slider. The main parameters that influence the thermal property of slider can be considered to be the heater height, heat generation rate, and the heat conductivity coefficient of the material. The change of the slider flying height is determined by the air bearing force and the air bearing surface thermal extrusion at the head/disk interface. Simulation results provide a basis for the design of heater in head slider and analysis of dynamic characteristics of air bearing.