Content area
Full Text
Introduction
Residual heat removal pumps (RHRPs) are key equipment of residual heat removal (RRA) system in 1000-MW nuclear power plants, and their level of safety requirements is second only to nuclear reactor coolant pumps. They circulate coolant through RRA heat exchangers and the reactor vessel when no reactor coolant pumps are operating to maintain the plant in cold shutdown condition. Their reliability plays an important role in the stable operation of nuclear power plant. The RHRPs are used for the following purpose: first, circulating primary coolant through RRA heat exchangers to remove residual heat, thereby achieving and/or maintaining cold shutdown of unit; second, draining the coolant in the reactor cavity (only unloading fuel entirely). They are brought into operation at pressure and temperature in reactor coolant system of 28 bar absolve and 180°C, respectively. In order to ensure the safety of nuclear power plants, the RHRPs should have low vibrations under different operating conditions. Clearly, it is very important and significant to investigate the RHRP performance based on the fluid-structure interaction (FSI).
In some multi-physics problem cases, the flow encompasses a body and affects the structure strongly, which may lead to the deformation of that body, and at the same time, the flow is influenced obviously by the change in shape of the body. Consequently, in many mechanical engineering systems, FSI was considered as an effective numerical method to solve these problems. Some researchers applied FSI to study the structure vibration induced by turbulent flow in Francis hydro-turbine, the hydrodynamic torque on oscillating hydrofoil, and the aeroelastic behavior of an oscillating blade row.[1]-[7] The temporal and spatial features of the turbulence in complex configuration can be obtained effectively using a coupling calculation model with the finite element formulations of fluid and solid dynamics.[8],[9] Eladi et al.[10] predicted the performance of valveless micropump considering FSI between a membrane and the working fluid. Pei et al.[11] investigated the characteristics of transient flow in a single-blade centrifugal pump using a partitioned FSI solving strategy. Jiang et al.[12] used the FSI method to study the critical speeds and unbalanced responses of rotor systems which considers annular seals in multi-stage pumps. RL Campbell and EG Paterson[4] developed a quasi-steady response FSI solver model...