NUMERICAL SIMULATION AND FLOW FIELD MEASUREMENT OF HIGH EFFICIENCY AXIAL-FLOW PUMP

摘要

In order to analyze the flow characteristics of a high efficiency axial-flow pump, the behavior of the flow in an adjustable axial-flow pump bas been analyzed by numerical simulations of the entire stage based on Fluent software. The prediction data shows agreement with the experimental results. Numerical results show that the static pressure on pressure side of rotor blades increases slightly at radial direction, and remains almost constant in circumferential direction at design conditions, while it increases gradually from inlet to exit on suction side along the flow direction. The static pressure, total pressure and velocity at inlet, rotor blade exit and stator outlet were measured by five-hole probe. The experimental results show, inlet flow is almost axial and the prerotation is very small at design conditions. The meridional velocity and circulation distributions are almost uniform at rotor blades exit at design condition. The residual circulation still exists at downstream of stator, and the absolute flow angle at radial direction is almost consistent at design conditions, but C_u increases linearly from hub to tip at small flow rate conditions. To determine the influence of the hub leakage, a contrast experiment was accomplished. The measurement results show that hub leakage results in the decrease of efficiency, and the meridional velocity and circulation at rotor blade exit, especially near hub leakage region are influenced by the leakage.