伴有滑动床的水砂浆体倾斜管道流动研究

为进一步研究伴有滑动床的倾斜浆体管道砂颗粒输送规律，应用力平衡理论，研究了悬浮层、滑动床层速度以及滑动床厚度求解方法，由此给出了倾斜管道淤积临界速度迭代求解方法。同时，应用悬浮层剪应力线性分布假设，并借助普朗特经验公式，给出了滑动床上方速度分布模型。粗砂管道水力输送实验数据表明:（1）淤积临界流速与颗粒粒径和输送浓度负相关，输送浓度不变时，淤积临界流速与管道倾角大小正相关。与模型计算结果对比表明淤积临界速度计算值和实测值最大偏差为13%；（2）随着管道倾角增加，最大速度点位置有向上偏移的趋势。与计算结果对比表明上层速度分布理论模型计算值和实测值偏差不超过10%。结果表明力平衡理论和剪应力线性分布假设能够较好地用于伴有滑动床的倾斜粗砂浆体管道淤积临界速度和滑动床上方速度分布预测研究。

Study on the flow of water sand slurry with sliding bed in inclined pipe

In order to further study sand particles' transport rules in the inclined slurry pipe associated with the sliding bed, force balance theories are used to study the method for evaluating the suspended layer and sliding bed velocities as well as the sliding bed thickness, and an iterative method for computing the deposit critical velocity is given. Meanwhile, the shear force linear distribution assumption is used and with the aid of prandt empirical formula, a velocity distribution model above the sliding bed is given. Experimental data of coarse sand pipe hydraulic transportation show that the deposit critical velocity is negatively correlated with the particle size and concentration, and it is positively correlated with the pipe dip angle when the transportation concentration is kept constant. The comparison between the calculated results and the measured results show that the maximum deviation of the calculated value from the measured value is 13%. The experimental data also shows that with the increase of the angle of the pipe, the maximum velocity point position has an upward trend. The comparison between the calculated and measured results shows that the deviation of the theoretical velocity distribution model and the measured value is not more than 10%. Results show that the force balance theory and the linear hypothesis of the shear stress distribution apply well in the research of deposition critical velocity and velocity distribution above sliding bed in the inclined coarse sand slurry pipe accompanied with the sliding bed.