Multi-objective Optimization And Dynamic Performance Simulation Of Marine Steam Generator

Compared with conventional power plants,nuclear power plants have the advantages of high energy density and no oxygen.However,the large space occupied by nuclear power plants has become one of the main problems restricting the development of nuclear-powered ships.How to effectively reduce the size of nuclear power plant and make its layout more compact has become an important indicator to reflect the technical level of nuclear power plant.As an effective means,multi-objective optimization can reduce the space occupied by nuclear power plants and improve the maneuverability of ships under the premise of keeping the output power of steam generators unchanged.In addition,the steam generator is the key hub connecting the primary and secondary sides of the nuclear power system,and its dynamic characteristics can directly reflect the performance of the whole secondary loop system to a large extent.The high difficulty and high risk of field test can be avoided by simulating the dynamic characteristics of steam generator and optimizing design and comparative verification of different operation strategies.The independent research and development of Marine steam generator and its dynamic characteristics are of great significance for promoting the application of Marine nuclear power and improving the maritime defense capability of China.In this paper,the Marine steam generator for thermal design,volume weight of the steam generator,an important structural parameters,selection of the pipe diameter,pitch diameter ratio,the circuit of coolant flow velocity,the circuit work pressure,primary circuit cooling agent import and export temperature and main steam pressure and so on seven secondary circuit optimization variables,and the steam generator circuit resistance,circulation ratio,the number of the pipe and with constraints on parameters such as total height,volume weight of the steam generator is realized by using particle swarm optimization(pso)double objective optimization.Simulation platform based on GSE steam raw dynamic simulation model is established,including the steam generator of ontology,primary circuit coolant regulator,water supply system,and the reactor power control module,the steam generator water level control module,for jelly or decreasing the load of pipe pressure control module,control module,integrated to build nuclear power system,the secondary circuit on the circuit coolant average temperature and temperature operation and the two kinds of operation policy control,the dynamic characteristics of a steam generator is studied,analysis the advantages and disadvantages of different operation strategies.According to the research results,the weight and volume of the steam generator can be optimized by 30.92% and 21.69% respectively.The optimized results meet the actual working needs of the steam generator,but the cycle rate of the steam generator decreases after optimization,which is not conducive to the stable operation of the steam generator.Both the coolant average temperature constant temperature operation control scheme and the variable temperature operation control scheme can realize the steady state and variable condition operation of the steam generator.The saturated steam pressure in the load reduction process of the constant temperature control scheme is up to 1.28,which reduces the safety and stability of the secondary loop equipment operation.Under the variable temperature control scheme,the maximum saturated steam pressure is 1.22 during the load reduction process.Under the variable temperature control scheme,the load reduction from the second working condition to the third working condition shortened by 50 S,but the parameters of the first and secondary sides fluctuated to a certain extent.In the process of load reduction,the higher the load corresponding to the selected switching point,the shorter the load reduction time of the system,the smaller the disturbance of the power system,and the smaller the fluctuations of the main parameters of the primary and secondary sides of the steam generator.