Research On Modeling And Simulation Of Thermal Fluid Network In The Secondary Loop

The fluid network system(FNS)plays an important role in the overall efficiency quantification for both nuclear power plants(NPPs)and conventional power generation facilities.Nowadays,study on the FNS shows significance for improving the overall efficiency of various power generation facilities.The focus of this thesis is on the development of mathematical model for modeling and simulating the fluid network system.Also the mathematical models of equipments which are commonly involved in the NPPs are reasonably transformed for coupling with the FNS.Then the linear system of equations for the coupling system could be resolved numerically by introducing appropriate algorithms such as Lower Upper(LU)decomposition algorithm.In this thesis,the graphical modeling interface of the FNS is designed and developed by using the secondary development component of SVG and C sharp programming language.All kinds of fluid network components are set in the developed platform.The components are automatic numbered when builtin the platform for the topology identification of the connection between the fluid network components.The identified FNS partition in network when modeling completed.After the network is partitioned,a new calculation number is generated.A calculation matrix of different orders is generatedby the new calculation numbers and the topological relation between the components.Analysts can input and modify the parameters of the calculation numbers in the platform for the calculation of the fluid network.Also,the FNS start and pause controlled the analysis process,and the data real-time displayed in the platform.The simulation results show reasonableaccuracy in predicting the characteristicsfor the FNS of a typical NPP's secondary loop in steady state.And the transient performance of the fluid network mathematical system is perfectly conformed to the practical situation.Both of the steady-state and transient-state analysis provide the good confidence of the proposed modeling method and joint solution approach for predicting the performance of NFS in different situations.