Mechanical And Integrlty Analysis Of The Flywheel In Reactor Coolant Pump

Reactor coolant pump (referred to as the main pump) is the only continuous power source of the nuclear islands. It needs 60-year long causative time withstanding the test of extreme working conditions. As for the main pump flywheel, it still needs to provide coolant forced circulation under the power-off accident to avoid reactor core damage. Integrity of storage system plays an important role in the security of the reactor under power-off accident. Therefore, it is necessary to conduct the integrity analysis of the flywheel. Moreover, to ensure the pump supply quantity of flow under the power-off accident, it is also need to have the analysis of running down of the main pump.In this paper, ANSYS is used to build three-dimensional solid model of flywheel. Then ANSYS is used to have mechanical analysis, and proved the accuracy of the finite model via comparing with the result of analysis method and the result of finite element method. Stress distribution analysis of canned-motor pump of the reactor and influence of flywheel security is conducted via changing interference quantity and structure size. The analytical result shows interference quantity should be chosen between 0.4mm-0.6mm, and reasonable structure size is that the thickness of internal hub,Tungsten alloy and external hub is 0.149m,0.117m,0.055m respectively. Conducting mechanical analysis considering the preload force,centrifugal force,shearing force and pressure of the flow, the stress and displacement distribution is obtained in this paper. The result of the analysis is assessed according to RG1.14. It shows that the result meet requirements of specification.The result of the analysis by conducting ductility analysis shows the stress intensity factor is less than critical stress intensity factor, the flywheel won't appear ductile rupture. And the critical failure speed is 4344r/min through calculating, which is more than design speed (2250r/min). Appearing hypothesis of the worst damage of the assembly of the flywheel event, the structure is able to accommodate the flywheel fragments of energy. ANSYS-DYNA is used to conducting integrity analysis of pressure boundary. The result shows that motor shell can accommodate the flywheel broken pieces and the pressure border can't be destructed. Rotor deflection analysis under condition of earthquake and running down time is analyzed, the result shows the jam shaft accident won't happen.In this paper, the research approach, which is used on flywheel mechanical analysis is mastered and conducting the integrity analysis meanwhile. The result provides the basis for the integrity of the flywheel, and the study of rotor deflection also provides the reference to the study of the security of the main pump during the running down time.