基于叶片翼型负荷的螺旋离心泵叶轮域能量转换机理

Energy Conversion Mechanism on Impeller Domain of the Screw Centrifugal Pump Based on Vane Airfoil Load

为了研究螺旋离心泵叶轮做功原理以及能量转换机理,应用计算流体力学原理对100LN-7型螺旋离心泵进行数值模拟,由此获得螺旋离心泵叶轮域速度参数,在引入动静扬程和负荷系数基础上,将欧拉方程用速度表示,建立试验方案。在叶片负荷翼型理论下,应用欧拉方程将螺旋离心泵的能量转换与叶轮几何形状、尺寸联系起来,分析沿叶轮包角的能量变化,揭示螺旋离心泵叶轮域能量转换特性。结果表明叶轮作为泵内做功核心部件,其螺旋段螺旋推进作用提供了能量传递,离心段完成能量转换,叶轮的螺旋段螺旋推进作用和离心段的能量转换相互配合,构成了螺旋离心泵工作的过程。其中,叶片翼型负荷中的升力对叶片做功贡献最大,这一结论对于提高螺旋离心泵叶轮水力设计具有重要的意义。

In order to study the work principle and the energy conversion mechanism of the impeller of screw centrifugal pump, the screw centrifugal pump of type 100 LN-7 is simulated by using the theory of computational fluid mechanics. Thus, the parameter of velocity on impeller domain of screw centrifugal pump is obtained. On the basis of introduction of the head movement and the load factor, experimental program is established through expressing Euler equation with velocity. With the theory of the airfoil blade loading, Euler equation is used to connect the energy conversion of screw centrifugal pump with the geometric shapes and the size of impeller. The energy change along the angle of impeller is analyzed to reveal the energy conversion characteristics on impeller domain of screw centrifugal pump. The results show that the energy transfer is provided by the propulsion function of screw segment while the energy conversion is accomplished by centrifugal section. The two parts cooperate with each other and make up the working process of screw centrifugal pump. In particular, the lift of blade airfoil loading leaves the largest contribution to the work, which has the vital significance for improving the hydraulic design of the impeller of screw centrifugal pump.