Study On Natural Circulation Characteristics Of Molten Salt Fluid

In the context of the increasingly prominent energy problems in China today and the urgent need for energy structure transformation,the development of new nuclear energy systems is one of the important means.Molten salt itself also has good thermal expansion reaction performance,and has great potential for designing and developing natural circulation molten salt reactor systems.For this purpose,the Shanghai Institute of Applied Physics,Chinese Academy of Sciences designed and built a nitrate natural circulation reactor experimental platform circuit for this purpose,and extensively conducted experiments on this experimental platform to study the natural circulation reaction characteristics of molten salt.In this paper,firstly,the experimental design is carried out for the structure and functional characteristics of the nitrate natural circulation test loop,and two rounds of the temperature response of the molten salt pool and the wind speed response of the air cooling tower are performed.Based on the Python language,an object-oriented programming method is used to establish a mathematical and physical model for the nitrate natural circulation test loop system,and a data analysis program for the nitrate natural circulation test loop is developed.Then based on the obtained experimental data,with the aid of the developed data analysis program,the transient response characteristics,steady-state flow and heat transfer characteristics of the system are studied.Studies have shown that the flow state of nitrate in the main circuit can quickly respond to changes in wind speed,but the response to changes in molten salt pool temperature is lagging.The steady-state flowresistance characteristics of natural circulation are studied through steady-state data.The theoretical derivation shows that there is a power function relationship between the steady-state natural circulation flow rate and the heating power and the total resistance of the system,which is verified by experiments,revealing the natural circulation state of nitrate for the first time Index range under.The traditional empirical formula is evaluated and revised using experimental data.Aiming at the steady-state characteristics of the natural circulation of molten salt,the conclusions obtained from the experimental analysis are applied to the design and research of the primary circuit of a small natural circulation molten salt reactor,and a modular analysis program is developed to pass the influence of the main pipe diameter on the system height and the amount of molten salt Research and use a constrained dual-objective optimization method for optimization analysis to complete the primary loop design.The research conclusions of this article can provide important references for future experimental research and the design of molten salt natural circulation system.