Whittington R B, Harkness J
Biorheology. 1982;19(1/2):175-84. doi: 10.3233/bir-1982-191-220.
The viscometers used were: (a) a proprietary rotational coaxial-cylinder instrument; and (b) a Harkness capillary-tube viscometer. In (a), the mean shear-rate is selected by the choice of rotational speed. In (b), the wall shear-stress is selected by the choice of driving-pressure. If the viscosity is varied, the mean shear-rate varies, at constant wall shear-stress. The present paper attempts to show how, in principle, a complete family of "constant-rate" (rotational) curves can be computer-plotted from two suitably-spaced capillary-tube measurements. The reverse process, involving the correction of "playback" errors, is touched upon. A variable "Einstein coefficient" is derived from the principal parameters in the computer solution; and the basic problems of compatibility in "rates of shear" are discussed.
(a) 一种专利旋转同轴圆柱仪器；以及 (b) 哈克尼斯毛细管粘度计。在 (a) 中，通过选择转速来选定平均剪切速率。在 (b) 中，通过选择驱动压力来选定壁面剪应力。如果粘度发生变化，在壁面剪应力恒定的情况下，平均剪切速率也会变化。本文试图说明，原则上如何根据两次适当间隔的毛细管测量结果，通过计算机绘制出一整套 “恒定速率”（旋转）曲线。文中还提及了涉及 “回放” 误差校正的反向过程。从计算机解决方案中的主要参数推导出一个可变的 “爱因斯坦系数”；并讨论了 “剪切速率” 兼容性的基本问题。
