Research on Axial-Flow Pump Inlet Velocity Field and Pump Flow at Different Operating Condition

Abstract

Abstract:The impeller inlet velocity field of axial-flow pump under the long straight pipe inlet was tested by using LDV technology. The axial velocity distributions of impeller inlet at three measuring lines, and origin interpolation integral flow measurement accuracy under three working conditions were analyzed. The results show that under the three working conditions of 0.8 Q opt , 1.0 Q opt and 1.2 Q opt , axial velocity backflow does not exist at three measuring lines, and distribution trend is more consistent. The axial velocity of measuring line one appears parabolic distribution, and the distribution under the two working conditions of 1.0 Q opt and 1.2 Q opt is more uniform than that under the working conditions of 0.8 Q opt ; The axial velocity at the hub side of measuring line two and three is greater, and increasing trend is faster. Error analysis shows that at the three measuring lines of 0.12 D, 0.22 D, 0.32 D axial distance from the impeller center, the maximum error of flow integration is 1.58% under the three working conditions. The flow can be measured accurately via the origin interpolation integral tool with the operability and applicability. Keywords