Heat Transfer Analysis And Calculation Of The Passive Residual Heat Removel Heat Exchanger In Advanced Pwr Nuclear Power Plant

Passive Residual Heat Removal Heat Exchanger (PRHR HX) is a key safety equipment of advanced PWR nuclear power plant, which provides decay heat removal for postulated LOCA and non-LOCA events. The PRHR HX is a C-tube heat exchanger located in the in-containment refueling water tank (IRWST) above the core promoting natural circulation heat removal between the reactor cooling system and the tank. The PRHR HX will keep the reactor coolant sub cooled and prevent coolant relief from primary circuit.In my research project, the Westinghouse AP1000 PRHR HX have been studied in detail, based on the studies, some of innovative theories on heat transfer have been developed. All these achievements will help to realize our own PRHR HX design technology with independent intellectual property rights. Theoretical calculations and analysis, Numerical simulation studies have been conducted in this project. The work principles, heat transfer performance and its calculation method of the PRHR HX have been studied at length.Firstly, based on the PRHR HX transfer mechanism, the heat transfer modes have been established. The different correlations of heat transfer coefficient under different heat transfer modes have been obtained as well. Secondly, we have put forward the calculation method (Element Method) innovatively and realized it using VB codes. Thirdly, the PRHR HX heat transfer process have been simulated by using FLUENT software, the flow field distributions and temperature field distributions of the water in IRWST have been achieved, and some of their change rules have been analyzed.The achievements of this project could provide theoretical supports for the design of PRHR HX of advanced PWR nuclear power plant. It will push the localization of Westinghouse AP1000 in China greatly, at the same time, improve the CAP 1400 research and development, which is a larger capacity nuclear power plant with independent intellectual property rights of China.