Modal Analysis Of Impeller Rotor And Research On Axial Force Measurement System Of A Certain Type Of Pump

Pump is an important equipment in the process of hydroelectric power generation.The reasonable and reliable design of pump is very important for the safe and stable operation of the whole hydraulic system.Cracks or even breaks in impeller blades of water pumps,as well as excessive axial force of water pumps,greatly affect the safe and stable operation of water pumps.Therefore,the static and modal analysis of pump components and the study of pump axial force measurement system are very important.In this paper,the finite element model of the core components of a pump is established,and the static analysis of the impeller is carried out.The influence of prestressing force in dry state(air)on the natural frequency of the impeller is analyzed,and the influence of pre-tightening force and geometric parameters of the end teeth on the structural modal performance of the impeller rotor is also analyzed.The axial force produced during the operation of the pump is studied,the causes and influencing factors of the axial force are analyzed,the model of the axial force measuring device is established,the design of the elastic disk is optimized,and the rationality of the overall design structure is verified.(1)The finite element analysis model of impeller is established,and the stress and deformation of impeller are calculated.The inherent modal analysis and prestress modal analysis of impeller are compared.The stress and deformation values of the impeller under different rotational speeds and the stress and deformation trends of the impeller are obtained.The first six natural frequencies of the impeller under natural and prestressing modes are calculated.(2)A simplified meshing model of end-face teeth is established,and the relationship between stiffness correction factor and dimensionless factor is established.The influence of geometric parameters of end-face teeth on stiffness characteristics is obtained.(3)A simplified model of Impeller-Rotor structure is established by using end-tooth meshing as the connection mode of impeller-rotor.The natural frequencies of Impeller-Rotor structure under different pretightening forces and geometric parameters of end-tooth are obtained.(4)The model of axial force measuring device is established,and the elastic disc is optimized according to the yield limit and sensitivity parameters.The stress,strain and deformation of the elastic disc under different numbers and thickness of the elastic disc and the stress and deformation of the whole device under the maximum axial force are obtained.