对超临界二氧化碳(S-CO2)在螺旋管内的对流换热性能进行模拟和试验研究.探讨了热流密度q、质量流量G、节距P、管内径d、螺旋半径R等流动、结构特性对流动传热的影响,并对各结构特性灵敏度做了量化分析;搭建了闭式循环的S-CO2测试平台,对螺旋管内S-CO2对流换热性能进行了试验研究,并基于试验工况数据验证了数值模拟的准确性;对数据进行处理,拟合出了 S-CO2的传热关联式.该研究为S-CO2螺旋管式换热器的热力设计方法奠定了基础,并在核电及光热发电领域具有一定的工程应用价值.
Numerical and experimental studies are conducted on convective heat transfer performance of carbon dioxide(S-CO2)flowing in a heated vertical helically coiled tube under supercritical pressure.The influence of flow characteristics and structural characteristics such as heat flux q,mass flow rate G,pitch P,tube inner diameter d,and spiral radius R on heat transfer are discussed,and the sensitivity of each structural parameter is studied quantitatively.A closed-loop S-CO2 test platform was built to conduct experimental research on the convective heat transfer performance of S-CO2 in the helically coiled tube,and the accuracy of the numerical simulation is verified based on the experimental data.Finally,the heat transfer correlation of S-CO2 is fitted.The research has laid foundation for the thermal design method of S-CO2 spiral-wound heat exchanger,and has certain engineering application value for the application and promotion of the spiral-wound S-CO2 heat exchangers in nuclear power and solar thermal power generations.