Investigation on Transient Thermohydraulics of a Plate Type Research Reactor

摘要

A thermohydraulic and safety analysis code has been developed with Fortran90 language to investigate the transient thermohydraulic characteristics of a plate-like fuel research reactor. For the development of this code, a series of corresponding mathematical and physical models were applied. All possible flow and heat transfer conditions during the transient were considered and the optional correlations were supplied. The usual finite difference method was abandoned and the integral technique was adopted to evaluate the temperature field of the plate type fuel elements. The reactor under research was composed of two kinds of assemblies:standard fuel assemblies (SFA) and control fuel assemblies (CFA). In order to simulate the loss of flow accident (LOFA), which was an anticipated accident of a research reactor, each fuel assembly in the whole core was modeled and simulated. The evolvement of the mass flux distribution was given out, and the variation of the temperature of fuel elements and coolant was also investigated. Furthermore, a whole SFA assembly was modeled to analysis the blockage of a channel in this assembly, which may happen during the lifetime of the reactor due to the fuel swelling. Results of coolant flow and temperature distribution under this condition were given out.