文献类型：期刊文献

英文题名：Investigation of flow deceleration effect on heat transfer characteristics of carbon dioxide during cooling in a horizontal double pipe at supercritical pressures

作者：Fu, Jian Liu, Hanyi An, Zhoujian Ding, Yong Du, Xiaoze Yang, Ting Wang, Yan

第一作者：Fu, Jian

通信作者：Wang, Y[1]

机构：[1]Lanzhou Univ Technol, Sch Green Energy & Storage, Lanzhou 730050, Peoples R China;[2]Lanzhou Univ Technol, Sch Energy & Power Engn, Lanzhou 730050, Peoples R China;[3]Guizhou Inst Technol, Sch Aerosp Engn, Guiyang 550025, Peoples R China;[4]Jiu Quan Ok Seed Machinery Co Ltd, Jiuquan 735000, Peoples R China

第一机构：Lanzhou Univ Technol, Sch Green Energy & Storage, Lanzhou 730050, Peoples R China

通信机构：corresponding author), Lanzhou Univ Technol, Sch Green Energy & Storage, Lanzhou 730050, Peoples R China.

年份：2026

卷号：172

外文期刊名：INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER

收录：;EI(收录号：20255119749843);Scopus(收录号：2-s2.0-105025051422);WOS:【SCI-EXPANDED(收录号:WOS:001644154900002)】；

基金：This work was supported by the National Natural Science Foundation of China (Grant No. 52276197) , Gansu Special Project for Science and Technology Commissioners (Grant No. 25CXGA072) , Guizhou Provin-cial Major Scientific and Technological Program (XKBF(2025)031) and Guizhou Science and Technology Innovation Leading Talent Workstation (KXJZ(2025)024) .

语种：英文

外文关键词：Supercritical carbon dioxide; Cooling process; Horizontal double pipe; Numerical simulation; Abnormal heat transfer; Flow deceleration effect

摘要：The supercritical carbon dioxide (SCO2) Brayton cycle is a promising technology for renewable thermal power generation, recognized for its compact layout and high thermodynamic efficiency. Achieving higher cycle efficiency requires cooling the working fluid near its critical point, where the thermophysical properties of SCO2 undergo drastic changes near the pseudo-critical temperature, leading to abnormal heat transfer. It poses a critical challenge for cooler design in SCO2 systems. The present study investigates the heat transfer characteristics of SCO2 during cooling in a horizontal double pipe through numerical simulation. The effects of key boundary conditions (mass flux, heat flux, and operating pressure) are examined, and the mechanisms underlying abnormal heat transfer phenomenon, including heat transfer enhancement (HTE) and deterioration (HTD), are analysed. Results reveal that these phenomena are primarily induced by the flow deceleration effect. A new heat transfer correlation considering the effect is developed, which predicts 87.23 % of the numerical data within a +/- 20 % error band, outperforming existing models. The findings provide a theoretical basis for the optimized design of cooler in SCO2 Brayton cycle.