深海扬矿泵内部非定常流体径向力研究

Study on unsteady fluid radial force in deep-sea lifting pump

基于深海扬矿泵是深海采矿系统的关键设备,泵内部流动较复杂,无法用公式对流体径向力进行理论计算等,采用试验和数值模拟方法对其作用规律以及产生机理进行研究。首先,对泵内流场进行定常数值计算。然后,进行非定常数值计算,得到泵内压力和径向力的时域和频域图。研究结果表明:在对泵内流场进行定常数值计算时,发现扬程、功率和效率的模拟值与试验值较吻合,从而验证了数值模拟方法的可行性;叶轮和导叶的动静干涉是泵内产生压力脉动和不平衡径向力的重要原因;泵内压力和径向力均呈周期性脉动;叶轮内的压力脉动周期和主频与导叶的叶片数相关,导叶内的压力脉动周期和主频与叶轮叶片数相关,而两者的径向力脉动周期和主频则均与叶轮叶片数相关。

Considering that deep-sea lifting pump is the key equipment of deep-sea mining system, the internal flow is complex, and the radial force of the fluid can not be calculated theoretically by formulas, the experimental and numerical simulation methods were used to study the regular and the production mechanism. Firstly, the steady flow field in the pump was calculated. Then, the unsteady flow field in the pump was calculated, and the time-domain and frequency-domain diagrams of pressure and radial force in the pump were obtained. The results show that the simulated values of the external characteristic curve agree well with the experimental values, which verifies the feasibility of the numerical simulation method. The dynamic and static interference between the impeller and the guide vane is an important cause of pressure pulsation and unbalanced radial force in the pump. The pressure and radial force in the pump have periodic pulsation characteristics. The pressure pulsation period and the main frequency in the impeller are related to the number of vanes during the pressure pulsation period and the main frequency in the vane are related to the number of impeller blades. The radial force pulsation period and the main frequency of them are only related to the number of impeller blades.