Three-dimensional modeling and thermal hydraulic analysis of high temperature gas-cooled reactor core

The high temperature gas-cooled reactor (HTR) is an advanced reactor with the characteristics of Generation IV nuclear energy system which has attracted wide attention due to the excellent performances of inherent safety, economy, high efficiency and low carbon environmental protection. Accurate and reliable thermal hydraulic analysis is of great significance for studying the flow and heat transfer in the core of HTR. Based on the coolant flow and heat transfer process in the core of HTR, this study establishes a three-dimensional coupled model by using CFD (Computational Fluid Dynamics) software firstly, and the flow and heat transfer process of helium coolant is simulate in the core. The temperature variation in the reactor is calculated under the conditions of steady-state operation of the HTR core, and the calculation results by the present models were compared with calculated results from the benchmark software of Thermix and the related published results. The results showed that the average temperature of the outlet section is 759.6℃, and the maximum relative error with the published data is 1.25%. The steady-state results under the full power conditions based on the three-dimensional model are in good agreement with the calculation data from those of THERMIX. It stated that the three-dimensional model can be employed to simulate the thermal hydraulic analysis for HTR. On this basis, the heat transfer characteristics of core is simulated under 50% full power, and the are result helpful for the operation and design of HTR. (author)