垂直管水力提升临界淤堵流速的实验

Experiment on Critical Velocity in Vertical Pipes for Hydraulic Lifting

通过试验分析研究垂直管水力提升临界淤堵流速,推导垂直管水力提升临界淤堵流速的半理论半经验公式。颗粒向上运动主要受颗粒周围水流流速影响,当管壁处的流速与此位置的颗粒沉速基本一致时,垂直管处于临界淤堵状态。垂直管水力提升临界淤堵流速不仅随粒径增大而增大,而且随提升浓度增加而增大。所推公式反映了影响临界淤堵流速的主要因素,能够较好的预测临界淤堵流速,对于管路系统设计和运行有较大实际意义。

The critical lifting silt velocity for vertical hydraulic lifting is investigated by experiments, and the partly theoretical and partly experienced formula on the critical lifting silt velocity calculation for vertical hydraulic lifting is derived. The upward movement of the particles in the vertical hydraulic lifting system is mainly effected by the flow rate of the surrounding water, while the flow rate near the tube wall is almost same as the particle settling velocity in static fluid, the vertical tube will be in the silt situation. The critical lifting silt velocity for vertical hydraulic lifting is not only increased with the increase of the partiCle size, but also increased with the increase of the pulp concentration. The developed formula can represent the dominant factors impacting on the critical lifting silt velocity, and well predict the critical lifting silt velocity, it has great practical importance for pipeline design and operation.