颗粒堆积多孔介质内幂律流体的流动阻力特性

摘要

Based on the Carman⁃Kozeny⁃Blake model and the contracting⁃expanding channel model, this study developed a new resistance model for predicting power law fluid flow through granular porous medium with homogeneous spherical particles. For the rheological properties of power⁃law fluid, by employing the average hydraulic radius theory, a modified Ergun type equation was expressed as a function of tortuosity, porosity, ratio of pore diameter to throat diameter, diameter of particles, and fluid rheological index. Every parameter such as A and B in the proposed model had clear physical meaning. The validity of the present model was evaluated by comparing the predicted friction factor to the published theoretical models and the experimental data correlations, the analysis results showed that the new model predictions were in good agreement with the existing documents data in a certain regime. At last, to further understand the flow resistance characteristic, the correlations of critical Reynolds number, the modified permeability and the inertia coefficient for power law fluid were also expressed.%为深入研究幂律型非牛顿流体在均匀球颗粒堆积多孔介质内流动的阻力特性，基于经典Carman⁃Kozeny⁃Blake模型及孔喉通道模型，提出一个新的预测模型。针对幂律流体的流变特性，利用平均水力半径理论，得到了于迂曲度、孔隙率、孔喉比、颗粒直径及幂律指数等重要参数修正的Ergun型方程表达式，且方程中的系数表达式A、B等各物理量都有明确的物理意义。对所建模型与文献中的理论模型及实验数据关联式比较的结果表明，新模型在一定流态区间内的阻力预测值与文献吻合较好。给出了幂律流体的临界雷诺数、修正渗透率及惯性系数的关联式。