Experimental and simulation analyses of the hydraulic complex internal flow characteristics in an axial pump based on varying frequency vibration ranges technique

Using computational fluid dynamics method, it was studying the effects of varying flow conditions on internal an axial-flow pump’s main flow characteristics and dynamics. The distribution of mean velocity, turbulent kinetic energy, and pressure variations at various flow rates are analyzed to examine the flow patterns in different flow structures. The simulation outcomes indicate that the vortex’s flow structure and transportation are heavily reliant on the flow, particularly for the extension of a vortex, the emergence of an induced vortex, and the portion of the flow that divides on the tip. At a small flow rate, no tip separation vortex exists. However, as the flow rate increases, and the intensity of tip flows increases. A vortex appears near the leading edge of the blade for an augmented flow rate. Additionally, as the flow rates increase, the leakage vortex core’s radial position moves inward. The main-stream characteristics are also influenced by large flow conditions, especially near the shroud, since more energy is exchanged between main flows as well tip. When flow condition is low, the pump’s head decreases due to greater energy loss. Increasing the flow of pump rises head lift by different times of design flow condition. Consequently, curves of Q-H have obvious positive curvatures. The frequency of the pressure fluctuations observed under high flow conditions is 50 Hz at different monitoring points. Development and evolution laws for the vortex core region are essentially the same as those for the vanes’ streamline figure. Under a design flow rate, the efficiency relative variation was less than 4%.