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为研究颗粒粒径对深海采矿提升泵工作性能影响,采用RNGκ-ε湍流模型和Hinze-Tchen颗粒湍流粘性系数模型,运用Fluent软件对采矿提升泵内固液两相流进行数值模拟,比较不同的颗粒粒径对采矿提升泵内颗粒浓度、速度、压力分布的影响,进而分析颗粒粒径对扬程、效率等工作性能的影响,指导深海采矿提升泵的设计。研究结果表明:在转速、流量、颗粒体积分数不变情况下,随着颗粒粒径增大,泵的扬程和效率都逐渐下降;叶轮叶片中前部流道内浆体的颗粒浓度大幅上升,叶轮流道内颗粒动态沉积更加严重,叶轮流道过流面积随之减小,反而加大了叶轮流道内贯流的相对速度,从而有效地抑制了边界层分离的发生,但在叶轮叶片中后部压力面上浆体压力下降幅度较大,泵内浆体总压逐渐下降,扬程随之减小;在叶轮出口处,流道内固液两相流的速度差异增大,在叶轮出口处形成的射流-尾迹结构增强,并在空间导叶流道内形成更加明显的二次流及漩涡,从而加大水力损失,降低效率。实验证实了数值模拟方法的可行性及准确性。
In order to study the effect of particle size on the working performance of deep sea mining lift pump, RNGκ-ε turbulence model and Hinze-Tchen particle turbulent viscosity coefficient model were used. Fluent software was used to simulate the solid-liquid two-phase flow in mining lift pump. The effect of particle size on particle concentration, velocity and pressure distribution in mining lift pump is analyzed. Then the influence of particle size on working performance such as lift and efficiency is analyzed to guide the design of deep sea mining lift pump. The results show that the head and efficiency of the pump decrease gradually with the increase of the particle size when the rotation speed, flow rate and particle volume fraction are constant. The particle concentration of the slurry in the front runner of the impeller blade increases sharply. The dynamic deposition of particles in the runner is more serious, the flow passage area of the impeller decreases with the increase of the relative velocity of the flow in the impeller runner, which effectively restrains the boundary layer separation. However, The pressure on the surface slurry pressure drop larger, the total pressure of the slurry pump gradually decreased, the head decreases; at the impeller exit, the flow channel solid-liquid two-phase flow velocity increases, the jet formed at the exit of the impeller - The wake structure is enhanced, and the more obvious secondary flow and vortex are formed in the space guide vane flow path, so as to increase the hydraulic loss and reduce the efficiency. The experiment proves the feasibility and accuracy of the numerical simulation method.