使用一种新提出的用以确定Eyring流体有效黏度η*的算法，针对润滑油流变特性研究中一个常用假设，即γ=△u/h进行了深入探讨，给出润滑油牛顿黏度η、Eyring流体有效黏度η*和剪应变率γ与重载热弹流润滑副的摩擦因数μ之间的关系。结果表明：在润滑副尺度很小或类似的低温场合，传统假设γ=△u/h能够近似成立，摩擦因数主要取决于润滑油的有效黏度。然而，在润滑副尺度很大或类似的高温场合，γ=△u/h不能成立，此时摩擦因数不但与有效黏度有关，还取决于剪应变率的变化，故之前关于此类问题的摩擦因数的研究是不准确的。
Using a new proposed algorithm for the effective viscosity η* of an Eyring fluid, a common assumption γ=△u/h is discussed in the analysis of lubricant rheology, the relations of the friction coefficient μ of heavily loaded line contact thermal elastohydrodynamic lubrication with the Newtonian viscosity η, the effective viscosity η*, and the shear-strain rate γ of the Eyring fluid are studied theoretically through a strict numerical solution of a thermal elastohydrodynamic lubrication problem. Results show that, when the size of a contact is very small or in other similar cases with low temperatures, the traditional assumption of γ=△u/h can hold approximately, the friction coefficient, therefore, is dominated by the effective viscosity of the lubricant. However, when the size of the contact is very large or in other similar cases with high temperatures, γ=△u/h can no longer hold, the friction coefficient is mainly controlled not only by the effective viscosity but also by the change of the shear-strain rate, so the previous studies are inaccurate.
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