The role of variable viscosity on the heat transfer in non-Newtonian fluid flow has not been adequately explored in the past. Typically, non-Newtonian fluids are described by the power-law type behaviour as $\tau =K{\dot{\gamma }}^n$ ($\tau :$ shear stress; $K:$ consistency index; $\dot{\gamma }:$ shear rate; $n:$ power-law exponent). The viscosity correction factor in the form of ${\left(\frac{K_w}{K_{\infty }}\right)}^m$ ($w$: wall; $\infty$: bulk) is a function of $n$. Traditionally, the Sieder-Tate correction for Newtonian fluid, ${\left(\frac{{\mu }_w}{{\mu }_{\infty }}\right)}^{-0.14}$ was the popular choice (${\mu }_w$: fluid viscosity at the wall, ${\mu }_{\infty }$: bulk) (Metzner et al. 1957). This is the first work on postulating the viscosity correction from the fundamental boundary layer analysis in non-Newtonian fluid. The mathematical predictions are validated with the literature experimental data. Inaccurate estimation of the viscosity correction leads to under- or over-predictions of the heat transfer coefficient, consequently, affects the effective heat transfer area. The correlations developed in this work would help in improved area calculations, thus, better performance and economic benefits.

过去，尚未充分探讨可变粘度对非牛顿流体流动中传热的作用。通常，非牛顿流体通过幂律类型行为描述为$\tau =ķ{\dot{\gamma }}^{ñ}$ （$\tau ：$ 剪应力 $ķ：$ 一致性指标 $\dot{\gamma }：$ 剪切率 $ñ：$幂律指数）。粘度校正因子的形式为 ${\left(\frac{{ķ}_w}{{ķ}_{\infty }}\right)}^{米}$ （$w$： 墙; $\infty$：批量）是 $ñ$。传统上，对牛顿流体进行Sieder-Tate校正，${\left(\frac{{\mu }_w}{{\mu }_{\infty }}\right)}^{--0.14}$ 是最受欢迎的选择（${\mu }_w$：壁上的流体粘度， ${\mu }_{\infty }$：批量）（Metzner等人，1957年）。这是从非牛顿流体的基本边界层分析中推测粘度校正的第一项工作。数学预测得到了文献实验数据的验证。粘度校正的不正确估计会导致传热系数的预测过低或过高，从而影响有效的传热面积。这项工作中建立的相关性将有助于改进面积计算，从而提高性能和经济效益。