剪切稠化流体在偏心圆环通道中的流动特性研究

本文以幂律因子n>1剪切稠化流体为研究对象. 针对剪切稠化流体的表观黏度随剪切速率变化呈现高阶非线性特性的问题,在非结构化网格中运用基元中心法对非线性粘性系数进行离散,并采用有限体积法对剪切稠化流体在偏心圆环通道中的充分发展层流进行数值计算. 结果表明,流体的幂律因子增大,会使基于达西摩擦因子(f)表示流体流动特性的fRe(Re为雷诺数)数值显著增大. 流体通道偏心率的增大会使流动分布不均,且fRe数值会随着通道偏心率的增大而减小,增大半径比会使流体通道的流速增大,但对fRe数值的影响却很小.

Study on Characteristics of Dilatant Fluid Flows in Eccentric Annular Channel

This paper studies dilatant fluid whose power-law factor is greater than 1. To solve the problem of the apparent viscosity changing with the shearing rate and exhibiting highly non-linear feature,a cell-based central method is used for the non-linear viscosity coefficient discretization in unstructured grids. Finite volume method(FVM)is adopted for numerical simulation of fully developed laminar flow in eccentric annular channel. The calculation results show that the increase of power-law factor results in the apparent increase of fRe. The increase of eccentricity can lead to the asymmetrical distribution of velocity and reduce the value of fRe. In addition,the increase of radius ratio brings about the increase of velocity while having little impact on fRe.