The Research Of Experiment And Numerical Calculation Of The Axial Force On Floating Impeller In The Centrifugal Pump

In the production practice, the axial force of pump is usually very large, especially for severe running conditions or high-lift multi-stage centrifugal pump. If the design of pump is severe and operation conditions is bad can lead to bearing burned, seal of shaft is damaged or even break the shaft and cause some other accidents. In many cases, problems caused by axial force is more than caused by efficiency and wear. It becomes the determinant factor to affect the pump running well or not. Therefore, trying to eliminate or balance the axial force can not only improve the service life and efficiency of the submersible well pump, but also contribute to make the pump get a higher lift. The main contents of this paper are as follows:While the amount of the axial movement of impeller was0,2,4,6,8mm, corresponding the axial clearance of the rear pump cavity was14.5,12.5,10.5,8.5,6.5mm by artificially changing the axial position of the impeller. Respectively drawing out the curves of head, shaft power, efficiency, impeller axial force produced by pressure in the balance cavity and the axial movement of impeller when the range of flow rate varies from0.8to1.2. The result of this experiment as follows:in the range of flow rate varies from0.8to1.2,with the increase of the axial movement of impeller, head and efficiency were reduced, shift power was increased. Under the working condition of1.0Q, head and efficiency at x=4mm were reduced by1.19%and1.84%compared with x=0mm. When x>4mm, with the increase of the axial movement of impeller, head and efficiency rebounded. And the axial force could be effectively reduced by increasing the movement of the impeller.With water as the medium, standard k-ε turbulence model in multiple reference frames was used to simulate the whole flow field for unsteady incompressible condition on IS80-50-315centrifugal pump when the front and back sealing ring diameter of the impeller are equal, thus the performance and numerical calculation of axial force were got, and simulative curves of performance and axial force with head were drawn.The performance test of the centrifugal pump were made and measure the pressure of balance cavity. The simulative curves were compared with the test curves on performance and axial force. The result showed that these curves were close with each when the movement of the impeller is zero.Under the condition of parameters consent, while the amount of the axial movement of impeller was0,2,4,6,8mm. Simulating the full flow field numerical simulation of the centrifugal pump,analysis and calculate axial force.Drawing the pump performance and axial force along with the floating impeller shaft to move quantity change curve in different running conditions. The result showed that these curves were close with each other under working condition from0.8Q to1.2Q.