进料流量对深海矿石输送设备内流特性影响分析

为研究进料流量对深海矿石水力输送设备内固液流体流动规律及工作性能的影响,建立了由储料罐、钟阀与分离器所组成的设备的三维流场模型,应用计算流体力学理论和Fluent仿真软件对矿石水力输送设备内固液两相流场进行数值模拟,比较不同进料流量对矿石水力输送设备内颗粒浓度、速度、压力分布的影响,进而分析进料流量对矿石颗粒流入储料罐的速度、矿浆分离效率等工作性能的影响.结果表明:进料流量在200 ~320 m³/h内变化,储料罐不同截面处颗粒平均浓度稳定在8 kg/m³左右,最大浓度增大明显;随着进料流量增大,流体运动趋势更加复杂,流动愈加混乱,局部短路回流更加严重,储料罐内浆体压力逐渐增大,不同截面处静压力增大梯度相近,最大动压力变化幅度明显;随着进料流量增大,矿浆分离效率下降,分离器底部矿石颗粒堆积量增加,矿石颗粒流入储料罐的效率下降,实际工作过程应控制进料流量在280 m³/h以下.

Analysis on influences of feeding flow rate on flow characteristics in deep-sea ore hydraulic transport equipment

A three-dimensional fluid domain model of deep-sea ore transport equipment, which consists of a storage tank, a bell valve and a separator, was established, then the solid-liquid two-phase flow field in the equipment was simulated based on the computational fluid dynamics software-Fluent to study effects of feeding flow rate on solid-liquid flow pattern and operational performance of the equipment. Specially, influences of feeding flow rate on ore particle concentration, velocity and pressure distribution in the equipment were compared, and then ore particle velocity and slurry separation efficiency were analyzed. The results show that the average concentration of ore particles in different sections of the storage tank keeps being around 8 kg/m³, but the maximum concentration increases obviously when the feeding flow rate varies in the range of 200-320 m³/h. With increasing feeding flow rate, the fluid motion is more complicated, and the flow becomes even more chaotic, and the local reverse flow is more significant. The slurry pressure in the storage tank increases gradually, and the static pressure gradient is similar to each other in different sections, but the maximum dynamic pressure varies considerably. with the increase of feeding flow rate, the efficiency of ore slurry separation decreases, i.e. less ore particles flow into the storage tank and more particles deposit on bottom of the separator. In consequence, the feeding flow rate should be controlled at less than 280 m³/h under actual operational conditions of the equipment.