Modeling of Thermal Hydraulic Characteristics for a LBE-Cooled Fast Reactor Helical Coiled Type Steam Generator

Lead and Bismuth Eutectic (LBE) cooled fast reactor is attracting attention due to its advantages in safety. A thermal hydraulic analysis model is developed for an LBE cooled fast reactor helical coiled type steam generator, which could be used for predicting thermal hydraulic parameters distribution along the length of the tube. Based on two fluid model, the mathematical heat transfer model includes six regions: single water and vapor, subcooled boiling, saturated boiling, transition boiling and film boiling. In order to describe the heat and mass transfer between phases, the interphase model is presented. The steam generator is simplified with single tube concept and all the flow variables are evaluated at each point of the grid in which the domain is discretized. Full load condition and a postulated scenario, such a flow rate step changed in secondary side, is calculated in this study. The results showed that the changing process of the thermal hydraulic parameters of helically coiled steam generator conforms to the qualitative mechanism analysis results of thermal hydraulic analysis.