Abstract: In order to compute and analyze the blade stress in reactor coolant pump of a 300 MWe nuclear power plant in China , from the viewpoint of safety performance, the fluid-solid coupling technique is adopted to solve the fluid and solid coupling equation. Theoretical analysis shows that the blade stresses mainly include tensile stress caused by centrifugal force, bending and torsional stresses induced by flow-field pressure, and thermal stress brought by temperature field. From the analysis results, it is concluded that the max equivalent (Von-Mises) stress exists in fixed supports and the blade stress does not have strict periodicity, and the disordered distributions of blade stress lies in the complex internal flow. The differences between impeller and guide vane are proved by comparison of theory and simulation and the main factors are explained. Lastly the intensity examination proves that the intensity of the reactor coolant pump meets the requirement of ASME. This could be used for improving aerofoil design and ensuring performance and intensity.

Key words: Equivalent(Von-Mises) stress, Fluid-solid coupling, Intensity examination, Reactor coolant pump