Abstract:In order to predict the stress and deformation of blades in an axial-flow pump, a coupled solution of flow field in the pump and structural response of the blades was established by using two-way coupling method on Ansys platform-Workbench where CFX was used to compute the flow field, and Ansys dynamic structure code was applied to analyze the stress. The flow field prediction was based on the Reynolds-averaged N-S equations and the RNG two equation k-ε turbulence model; the structure response was handled by the elastic structural dynamic equations. Not only the deformation and stress distribution characteristics caused from fluid-structure interaction were identified, but also the influence of the interaction on the head and efficiency of the pump was analyzed. The results indicated that the maximum displacement occurs on the blade leading edge at impeller tip, but a smaller displacement appears on the blade trailing edge and in the blade root. A significant stress concentration occurs in the inlet side and the contact area of the blade root and the hub. All the stress level and deformation in the blades reduce steadily with increasing flow rate. The head and efficiency predicted by fluid-structure interaction model are lowered compared with those by the rigid structure model.However, this reduction in stress and deformation is very small.
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