热力发电2023，Vol.52Issue(11)：1-9,9.DOI:10.19666/j.rlfd.202301010
竖直上升直肋管内超临界二氧化碳换热特性与肋结构优化
Heat transfer characteristics of supercritical carbon dioxide and structural optimization in vertical straightly-ribbed-tube
摘要
Abstract
The high-performance supercritical CO2 heat exchanger is the key core equipment to realize the efficient and compact S-CO2 Brayton cycle system.S-CO2 has a low heat transfer coefficient in the smooth channel,and seeking high heat transfer performance and low-resistance heat transfer structure is the key to the development of efficient and compact heat exchangers.Five-axis EDM was used to fabricate the straightly ribbed tube,and the heat transfer behaviors of S-CO2 in the four-headed straight rib tube was experimentally studied,the effect of flow parameters on the heat transfer characteristics of the straight rib tube was systematically analyzed,and the difference in the heat transfer performance between the straight rib tube and the smooth tube was quantitatively evaluated.The influence of structural parameters on the enhanced heat transfer and resistance characteristics was studied by numerical simulation method,and the optimal straight rib tube structure was obtained.The results show that increasing the pressure and mass flow rate can reduce the wall temperature,improve the convective heat transfer coefficient,and the average heat transfer capacity of straight rib tube is about 1.96 times that of smooth tube.Compared with smooth tubes,straight ribbed tubes can effectively delay the occurrence of heat transfer deterioration,the ability to delay the occurrence of heat transfer deterioration by using straightly-ribbed tubes is increased by 0.3～1.8 times.When the fixed rib width W=0.5 mm and the rib height H=2.5 mm,the PEC is the best,and the value of PEC is 1.58.However,the fixed rib height is H=0.5 mm,ε=0.33,and PEC of the straightly-ribbed tube is the best,with the value of PEC is 1.22.关键词
直肋管/超临界二氧化碳/结构参数/强化传热/优化设计Key words
straightly ribbed tube/supercritical carbon dioxide/structural parameters/enhancing heat transfer/optimal design引用本文复制引用
王亚慧,雷贤良,刘云帆,方寅,李雨声..竖直上升直肋管内超临界二氧化碳换热特性与肋结构优化[J].热力发电,2023,52(11):1-9,9.基金项目
国家自然科学基金项目(U1867218) （U1867218）
中国华能集团有限公司总部科技项目(HNKJ20-H87-04)National Natural Science Foundation of China(U1867218) （HNKJ20-H87-04）
Science and Technology Project of China Huaneng Group Co.,Ltd.(HNKJ20-H87-04) （HNKJ20-H87-04）
