基于CSR1000的燃料堆内辐照验证试验回路试验段初步概念设计与分析

Pre-Conceptual Design and Analysis of a SCWR-FQT Loop Test Section Based on CSR1000

提出了2种基于中国超临界水冷堆(CSR1000)燃料元件的燃料验证试验回路试验段的概念设计方案——2×2组件方案、3×3组件方案;利用MCNP程序和CFX程序进行了中子学、热工水力学分析,并对不同方案进行初步评价。分析结果表明:2种方案均具备工程可行性,满足燃料验证试验需求,但两者存在显著的性能差异;2×2组件方案的燃料棒功率为23.6~25.3 k W,平均功率为24.3 k W,组件的径向功率峰因子为1.04;3×3组件方案的燃料棒功率为15.9~26.7 k W,平均功率为21.4 k W,组件的径向功率峰因子为1.25;3×3组件方案的组件功率峰因子较大,不利于功率展平,限制了组件平均功率的提高。对采用无绕丝组件的热工分析表明:2种方案的冷却水出口温度均超过25 MPa压力下的拟临界温度,燃料芯块温度、燃料包壳外表面温度均低于热工限值且留有裕量。

Two preliminary conceptual designs of test section for fuel qualification test loop based on China＇s supercritical water-cooled reactor （CSR1000） fuel element is proposed, which are the 2×2 assembly design and the 3×3 assembly design. The MCNP code and the CFX code are used to proceed the neutron, the thermal-hydraulic analysis and the preliminary evaluation of different designs. The results show that the two designs are engineering feasible and meet the requirements of fuel qualification test, but there are significant differences in performance. The fuel rod power of the 2×2 assembly is 23.6 - 25.3 kW and the average power is 24.3 kW, while these values for 3×3 design are 15.9-26.7kW and 21.4kW, respectively. The radial power peak factor of fuel assembly for 3×3 design is 1.25, which is not conducive to fuel assembly power flattening, limiting the average power of the assembly. The preliminary thermal-hydraulic analyses with wireless fuel assembly indicate that the outlet coolant temperature of the two designs exceeds the quasi-critical temperature of the pressure of 25MPa, and the fuel pellet temperature and the fuel cladding outer surface temperature are lower than the design limits, allowing certain safety margins.