Experimental Study And Wet Modal Response Analysis Of Reactor Coolant Pump Impeller

Wet modal response analysis of the impeller of reactor coolant pump has great significance for guaranteeing the reactor coolant pump in a stable and reliable operation conditions. Calculating the natural frequency of the impeller of reactor coolant pump accurately during the design section, those are the foundation of reliability analysis on the reactor coolant pump. Since the effect of water, there are significant differences of the impeller natural frequency in water or air. The surface of the impeller in water will generate the added mass, and will change the mass matrix, stiffness matrix and damping matrix of the impeller. So, the natural frequency of the impeller is varied in water.The impeller of reactor coolant pump in complex boundary conditions with high-speed rotation during operation conditions. The complex boundary conditions cause some impact on the natural frequency of impeller. To solve the problem, the article will simplify the complex boundary conditions as the cylinder with water, and change size of the cylinder to obtain the natural frequency of impeller in different size of cylinder. The results show that, the natural frequency of the impeller is reduced when the distance decreases.In this paper, the influence of the nearby rigid distance B on the natural frequencies of a submerged disc is evaluated when the gap is very small. Moreover, the effects of the free surface distance A on the natural frequencies of the submerged disc are studied. In this paper, we mainly study the natural frequency of a submerged structure under the influence of the nearby rigid surface and the free surface by a disc. Finally, we will have some investigations on submerged disc, and compare the numerical results with the experimental results. The results show that the error experimental results and the numerical results of less than 10%to meet the requirements of precision engineering, and proved that the simulation result is reasonable.The content and conclusions of this paper will lay a good foundation and provide useful guidance for further study of reliability design of the reaction coolant pump and strength check of the impeller.