Performance analysis and comparison of different corrugated structures and a novel alternative elliptical twisted tube in supercritical CO2 tower solar receivers

The concentrated solar power generation system with supercritical CO2 as working medium has high cycle ef-ficiency, which can effectively reduce the volume of heat exchange equipment and reduce the investment cost. However, there is no systematic comparative study on the effect of tube structure on the performance of su-percritical CO2, but the structure of tubes has a significant effect on the heat transfer performance of supercritical CO2, so it is necessary to study it. In this contribution, we firstly analyze the effects of different structures of tubes on the performance of supercritical CO2. Then, we design a novel alternative elliptical twisted tube. Finally, we further analyze the effects of the novel tube on the heat transfer performance of supercritical CO2 by using the field synergy principle. The results show that the novel alternative elliptical twisted tube is the best structure. When the mass flow is 0.08 kg s-1, the heat transfer coefficient of horizontal arrangement is 1625 W m- 2 K-1, which is 107% higher than that of horizontal tube. And the heat transfer coefficient of vertical arrangement is 1620 W m- 2 K-1, which is 116% higher than that of vertical tube. These results will provide a guidance for the structural optimization of practical receivers.

Automated summary

This study investigates the effect of tube structure on the performance of supercritical CO2 in a concentrated solar power generation system. A novel alternative elliptical twisted tube is designed and its impact on heat transfer performance is analyzed using the field synergy principle. The results show that the novel tube structure exhibits superior heat transfer performance compared to traditional tube structures, providing guidance for structural optimization of practical receivers.