Analysis of static stress and vibration characteristics of the impeller in a tubular pump

Abstract The tubular pump blade vibrates due to water flow excitation force and centrifugal force, which is susceptible to damage. This will lead to the abnormal operation of pump unit. To acquire the static stress and vibration characteristics of the impeller, a unidirectional fluid-structure coupling (FSC) method is adopted for static stress analysis and modal analysis. The results indicate that under different conditions, the static stress and displacement deformation law of the impeller are the same. The static stress increases as the radius decreases, with the maximum value occurring at the intersection of pressure surface and hub. The displacement deformation increases continuously with the expanding radius, and the highest value of deformation occurs near the shroud. The values of the maximum equivalent stress (MES) and maximum total deformation (MTD) of the impeller gradually decrease as the flow rate increases from 260L/s to 380 L/s. The natural frequency of the impeller is lower in wet mode compared to dry mode, and the additional mass of the water medium has different effects on each order. The research can be used as a reference for designing tubular pumps optimally and improving their stability.