考虑气体稀薄效应修正Reynolds方程的新模型及其数值分析

New Modified Reynolds Equation for Simulating the Gaseous Rarefied Effects on Gas Film Lubrication in Hard Disk Drives

硬盘中磁头和磁盘之间的气膜厚度已接近或小于分子平均自由路径,为了更精确地模拟气膜的压力分布,Reynolds方程必须要考虑气体稀薄效应的影响。基于硬盘中常用的修正Reynolds方程——FK模型,提出一种修正Reynolds方程的新模型,并且通过最小二乘有限差分法求解该Reynolds方程。分别利用FK模型和新模型,研究气膜数对承载力和压力中心的影响,并比较2种模型的计算时间。结果表明,2种模型所得的数值模拟结果具有很好的一致性,但新模型的计算效率高于FK模型。

The thickness of the air bearing film in current hard disk drives （HDDs） approximates the molecular mean free path or less. To more accurately simulate pressure distribution of the air bearing film, Reynolds equation must be modified to account for the rarefaction effect.A new modified Reynolds equation derived from FK model was proposed.The modified new model was solved by using a meshless method,called least square finite difference （LSFD） method.The effects of the bearing numbers on the load carrying capacity and the pressure center were investigated by this new model and FK model.The computational efficiencies of these two models were compared.It is found that numerical results of the new model are in good agreement with those of FK model.The new model has higher computational efficiency than that of FK model.