Research on real-time simulation of heat exchanger in low temperature nuclear heating reactor

The heat transfer characteristics of the heat exchanger in 200 MW low temperature nuclear heating reactor were analyzed by efficiency-number of transfer units and the mean temperature difference method, respectively. Based on the reasonable mathematic and physical model for the coupled three natural circulation cross flows, the code of the real-time simulation of the heat exchanger was developed. Compared the Adams method with Gear method adopted to solve the stiff differential equations, the temperature distributions of two sides in the heat exchanger were obtained. In addition the interrelationship of coupling change of power, flux, and temperature in two sides of the heat exchanger was investigated. The results indicate that the error of both two calculation methods is less than 5% and the Adams method is faster and more suitable for the real-time simulation process. The results could be used to the accident analysis and design for 200 MW low temperature nuclear heating reactor.