常规压力对采用非牛顿学流体润滑的光滑碟片表面的作用
陈好升，李疆，陈大荣，王佳道
1.国家摩擦学研究所，清华大学，中国北京，100084
2.北京科技大学，机械工程系，中国，100083
摘要：为了研究与分析非牛顿学流体在润滑光碟表面时常规压力所产生的影响，包含这个常规作用力的一个修正的瑞诺德公式被建立。公式中对于第一常规压力不同的表述源自于瑞林-埃里克森第二流体定律和流体冲力公式。光碟表面润滑的结果被计算从而用在了的瑞诺德分析公式之中。在持久稳定的薄层润滑作用之下，常规的压力和负载受到正常速度的限制，因此在计算中可以直接省略。当光滑流体的高度变化或者润滑膜的厚度下降时，常规的速度下降，故此此时需要在计算中考虑到第一常规压力的不同所产生的影响。
关键词：非牛顿学流体、第一常规压力差分、磁性数据存储系统。
Normal Stress Effects in Slider-Disk Interface Lubrication with Non-Newtonian Fluid
Chen Haosheng1*, Li Jiang2, Chen Darong1, Wang Jiadao1
1. State Key Laboratory of Tribology, Tsinghua University, Beijing China 100084.
2. Department of mechanology, University of Science and Technology Beijing, China, 100083
Abstract
To analyze normal stress effects of non-Newtonian fluid in lubrication of the magnetic head-disk interface, a modified Reynolds equation including the effects of normal stress is established. The expression of the first normal stress difference in the equation is derived from the Rivlin-Ericksen second order flow equation and the fluid momentum equation. Lubrication results of the magnetic head-disk interface is calculated using the modified Reynolds equation. Under the condition of steady laminar lubrication, the pressure and the load capacity of non-Newtonian fluid is increased by the effect of the first normal stress difference, but the effect is constrained by the normal velocity and can be omitted in the calculation. When the slider flying height changes or the lubricant film thickness decreases, the normal velocity increases and the effect of the first normal stress difference need to be considered.
Keywords: non-Newtonian fluid, first normal stress difference, magnetic data storage systems