粗颗粒由于沉降太快,不容易输送。通过试验发现,其在管道中存在四种运动形式,其中,连续式推移可以实现连续输送,且能耗不大,是其最佳输送形式。在分析比较已有研究结果基础上,提出了管道中粗颗粒水力输送的最佳输送速度的影响因素,并利用试验结果,基于量纲分析法得到了粗颗粒输送临界速度的计算公式。该公式的平均误差在15%以下,可以用作粗颗粒管道水力输送临界速度计算的依据。
Among four typical movement status of large particles,observed in horizontal pipeline transport experiments,the best transport status of continuous movement is observed as bedload. On the bases of existing results,influence factors of velocity in the best transport status were founded by force analyzing and experimental study,which including volume concentration and particle size of large particals. On the base of theoretical analysis and existing research,with experimental results,a new calculation formula of transport velocity was suggested for large partical transport pipeline projects. Result shows that the average error of the formula is below 10%,which meets the requirement.