掺气非牛顿浆体圆管轴对称层流的理论分析

A Theoretical Analysis of Axial Symmetric,Laminar Pipe Flow of Non-New-tonian Slurry-Gas Mixtures

本文分析了圆管中宾汉浆体和伪塑性浆体与气体混合物的轴对称层流。结果表明,由于掺入气体改善了浆体的流动性,浆体的流速和流量增加,而压力损失减小。该减阻效果随着宾汉屈服准数增大(或伪塑性幂指数减小)而更显著。同时由于掺气减少了静压差,管道上升坡度促使掺气浆体的总压降进一步减小,而当下降坡度超过某限度时,掺气反而使总压降增大。

In this paper, the axial symmetric laminar pipe flow of the mixtures of gas and Bingham/pseudoplastic slurries is analysed theoretically. The results show that the injection of gas into slurry increases the velocity and flow rate of slurry and reduces the frictional pressure loss and total pressure gradient,due to the lubricating effect of gas and the reduction of static pressure gradient. The drag reduction is more remarkable with the increment of yield number of Bingham slurry or the decrement of flow behaviour index of pseudoplastic slurry. The pipe inclination enhances the reduction of total pressure gradient, and while its declination surpasses a certain limit,the injection of gas leads to the increment of total pressure gradient.