Abstract: In this article,combinating Bingham fluid's constitutive equation with momentum equation,the velocity distribution of Bingham fluid's flowing in the encircle pipe is obtained by means of dimension analysis,which is under the condition of laminar flowing.Moreover the effects of some parameters such as yield stress and pressure gradient on the velocity profile have been discussed:the difference of velocity distribution between Bingham fluid and Newtonian fluid increases with yield stress,the width of flow nucleus also increases with yield stress;as pressure gradient is smaller and the velocity profile becomes flatter,it means the width of flow nucleus increases.

Key words: Bingham fluid, flowing in encircle pipe, velocity profile, yield stress, pressure gradient

摘要： 将宾汉流体的本构方程与运动方程相结合,利用因次分析方法,推导出宾汉流体在环空中作层流运动时的速度分布规律.根据速度分布规律,讨论屈服应力和压力梯度等参数对宾汉流体环空层流速度分布剖面的影响:屈服应力增加,宾汉流体环空层流流动的速度分布与牛顿流体环空层流时的速度分布之间的差异加大,且流核宽度随屈服应力增加而增加;压力梯度减小,宾汉流体环空层流流动的速度分布剖面愈扁平,即流核宽度增加.

关键词: 宾汉流体, 环空流动, 速度剖面, 屈服应力, 压力梯度