The Influence Of Swept-Curved Blade And Different Attachment On The Hydraulic Performance Of Axial Flow Pumps

Axial flow pump is widely used in every sector of the national economic.The impeller is the core component of the Axial Pump Sets, The pump in many of the water transfer and drainage-irrigation pump station that are being builded or under construction are vane pumps. So the study of the influence in pump performance by impeller detail structure that has the instructing significance.Numerical modeling and mesh generation taking into account the different radial clearance, the swept blade and Staggered blades could be realized by geometric modeling software ICEM, TurboGrid. Based on the N-S equation and stand k-ε turbulence model, with the numerical model which is created by ICEM and TurboGrid, three-dimensional incompressible flow fields numerical analysis could be simulated by commercial3D software CFX. Analysis of internal and external characteristics of axial flow pump under different design scheme.The results that is through calculation and analysis to compare radial clearance leakage concluded:With the pressure difference between the inlet and outlet increasing, the relative velocity within the clearance also increases. When the enlargement of the gap and the relative velocity within the clearance increased, the clearance expanded. The leakage of blade tip and the hub area directly affected the outlet section velocity distribution and then affect the performance characteristics. Under the same flow conditions, the greater the leakage, the greater the performance degradation. Compared the gap’s influence on the impeller chamber outlet cross-section velocity distribution under different working conditions, it showed that the existence of the hub leakage under large flow condition resulted in the hub region near the hub side formed the backflow. Under the large flow rate conditions, the hub leakage obviously affected the pump efficiency. Te blade tip with rib was calculated,the results shows that blade with rational design has little effect on the character,but could increase the clearance presure, improved he cavitation performance on blade tip.Through the calculation of swept-curved blade and the performance curve, under condition of the airfoil unchanged, the blade surface pressure value of the analysis show that swept-curved blade overall performance changed little, the rational design can improve the efficiency of leaf area scope, improve the cavitation performance. Compared the difference of the minimum pressure on blade under different sweepforward angle and form, sweepforward18°is better than sweepforward9°. With same angle, the cavitation performance of linear and arc combination is better than only for straight line form.The staggered angle blade of axial flow pump was calculated, the flow situation in the channel was analyzed, the results show that under different angle blade shaft power difference between the original consistent Angle placed, imbalance between blade had a expand tendency.