轴流式核主泵卡转子事故下压力波特性OA

In order to accurately reflect the transient process and pressure wave propagation in an axial-flow nuclear main pump under accident conditions,a three-dimensional closed equivalent flow field model of the reactor primary circuit system was established.Based on computational fluid dynamics(CFD)methods,the transient pressure waves and hydraulic loads within the piping system during a main pump rotor seizure accident were investigated.The results indicate that rotor seizure in-duces a significant water hammer effect,causing local sudden pressure changes that propagate as pres-sure waves along the pipeline.The highest pressure peak(16.60 MPa)is monitored at the main pump inlet,while the lowest pressure trough(14.61 MPa)occurs at the pump vessel outlet.The pressure waves propagate from these locations along the pipeline and gradually dissipate.Significant hydraulic loads are generated at locations with changes in flow cross-section or direction changes.The maximum load 3.22×106 N occurs at a bend near the main pump inlet and the minimum load 8.94×105 N occurs at a bend near the reactor pressure vessel inlet.Spatially,the steam generator outlet exhibits higher pressure due to its proximity to the main pump inlet,and the top of the U-tube shows further increased pressure due to flow direction change.In contrast,the inlet section and resistance components expe-rience lower pressure,and the reactor pressure vessel inlet shows a more pronounced pressure drop due to its closeness to the main pump outlet.This study reveals the spatiotemporal evolution of pressure waves and hydraulic loads within the system under rotor seizure conditions,providing important engi-neering insights for safety design and transient dynamic analysis of reactor primary circuits.