Research On Optimal Design Of Hydraulic Performance Of Nuclear Pump Based On Agent Model

The nuclear pumps are the only rotating equipments in the nuclear power plant.The reactor core is mainly provided with circulating coolant through the nuclear pumps,and its performance stability is closely related to the safety of entire nuclear power plant.In order to prolong its service life and improve work efficiency,it is necessary to optimize the performance of the nuclear pump structure.The nuclear pumps are classified into nuclear main pump,nuclear class pump and nuclear class ? pump according to its safety level.Nuclear main pump is to provide energy for the reactor coolant to overcome the viscous resistance generated in the reactor,steam generator and pipeline.Nuclear class pump is the auxiliary pump second only to the nuclear main pump.Hydraulic performance is the main content of hydraulic machinery design,mainly including efficiency,head,cavitation and operating stability under partial conditions.With the rapid development of computer technology,the study of hydraulic performance automatic optimization of nuclear-pump flow-through components has become the focus of current research.The impeller and vane are important working parts of the nuclear pumps.This article focuses on the impeller and vane of nuclear main pump and nuclear class pump.The parametric model is built and hydraulic performance analysis is performed through CFX flow field simulation software.Data connection is done and the entire optimization process is carried out in software MATLAB.The main contents of this paper's work are as follows:One-dimensional hydraulic design and parametric modeling of the pump are finished at first.A one-dimensional design algorithm is written using the velocity coefficient method.Based on the basic performance parameters,the calculation of the main geometric parameters is realized.The parametric model of the impeller and vane of the nuclear pump is construct.A series of basic structural parameters can be used to quickly update the overcurrent components,and the influence of parameter interference can also be avoided.Based on the parametric model and initial design,single point and multi-point hydraulic performance optimization of nuclear main pump are realized.First,the parametric modeling of the impeller and vane is completed in the workbench through the meridian shape,blade placement angle and thickness,and the important shape parameters are extracted as optimization parameters.The hydraulic performance of single and multi-operating conditions is analyzed in CFX to obtain performance indicators such as efficiency and head.Finally,the head under the design conditions is the constraint condition,the hydraulic efficiency under the design condition and the hydraulic efficiency under multiple operation conditions are optimized for the two options.Finally,the multi-objective optimization of the hydraulic efficiency and cavitation performance of the nuclear secondary pump was studied under the constraint of head.A refined parameterized model of blade leading edge is established.The shape of blade leading edge is the research object.The optimal solution based on RBF proxy model is used to obtain the optimal Pareto frontier.Two-phase flow calculation is performed to prove that the cavitation optimization effect is obvious.