热管堆固态堆芯典型栅元设计优化

Design and Optimization of Typical Cells of Solid Core for Heat Pipe Reactor

热管堆固态堆芯设计是影响堆芯传热性能和结构完整性的关键问题。为避免固态堆芯设计中间隙热阻导致的温度和应力过大,本文建立了四种堆芯典型栅元的三维热力学模型,对不同填充物下间隙尺寸和栅元截面尺寸等关键参数进行了优化分析。结果表明,尽管高热导率的液态钠填充装配间隙能够有效降低燃料包壳和芯块温度,但热应力反而可能增大;圆管插入液态钠方案的热力学性能最优;固态堆芯方案中,六角管拼接氦气填充方案的热力学性能最优。

The solid reactor core design is a key problem in heat pipe reactor,which can affect the reactor heat transfer performance and structural integrity.To avoid the over high temperature and excessive stress caused by the gap thermal resistance,the three-dimensional thermodynamics models for typical cells of four reactor core designs have been established for optimal calculation with different fillings under the key parameters about gap size and cell section size.The result showed that,the fuel cladding and pellet temperature decrease effectively with filling the assembly clearance with liquid sodium which has high thermal conductivity,but the thermal stress increases instead.The thermodynamic performance of tubes with liquid sodium is the best;Among the solid core solutions,the thermodynamic performance of hexagonal tubes filling with helium is best in solid reactor core designs.