筒装料管道水力输送动边界流压力特性

为深入探讨筒装料管道水力输送过程中同种型号双车运行时所产生的动边界条件下有压管道内部断面压力分布以及压降特性问题,对型号100 mm×60 mm、荷载750 g的管道双车在30,40,50,60,70 m³/h等不同流量作用下两车车身环隙断面、车间断面的压力分布以及车组沿程压降特性进行试验研究和分析,两车运行时车间距离条件为10 cm.研究表明:当流量增大时各测试断面压力值增大;双车车体沿程压力呈现先减小后增大的趋势;沿水流方向,后车引起的压降值明显高于前车;后车环隙断面内,自固定边壁向动边界压力值呈现“降-升-降”趋势,前车环隙内则为总体下降趋势,且后车环隙压力梯度高于前车;不同流量条件下,车间断面内压力分布基本为管道边壁附近值较大,内部值较小,且分布不均匀,压力梯度随流量增大而增大.

Pressure characteristics of flow induced by moving cylindrical capsules in hydraulic capsule transportation

To explore pressure drop in a hydraulic capsule transportation pipeline and pressure between two moving capsules extensively, the pressure distribution in the annular gap between a capsule and the pipe, the pressure distribution between two capsules as well as the pressure drop across capsules were measured and analyzed by using two capsules(length-100 mm, diameter-60 mm, weight-750 g)in 10 cm apart at 30, 40, 50, 60 and 70 m³/h flow rates. It is shown that the pressure in each test section increases with increasing flow rate. At a certain flow rate, the pressure on the capsule body presents a minimum. The pressure drop across the second capsule is substantially higher than that across the first one. In the annular gap, the pressure is low on the pipe wall and capsule body, but is the highest in the middle of the gap. The pressure shows a decline downstream in the gap of the first capsule, further the pressure gradient in the gap of the second capsule is higher than that in the first one. Under various flow conditions, the pressure distribution between two capsules is uneven in some degree, but the maximum pressure is achieved on the pipe wall and the minimum one is nearly at the pipe centre. The pressure gradient between two capsules increases with flow rate.