大连理工大学学报2026，Vol.66Issue(1)：48-56,9.DOI:10.7511/dllgxb202601007
水平花瓣螺纹管内超临界二氧化碳换热数值研究
Numerical investigation on heat transfer of supercritical carbon dioxide in horizontal petal-ribbed tubes
摘要
Abstract
The petal-ribbed tube is proposed to enhance the heat transfer of Brayton cycle heat exchangers,and investigation on heat transfer of supercritical carbon dioxide in horizontal tubes is numerically conducted.The heat transfer mechanisms under different operating pressures and petal numbers are studied.The non-uniform heat transfer under the coupling of buoyancy and petal swirling flow is analyzed through the temperature,velocity and turbulent kinetic energy distributions.The secondary flow strength caused by swirling flow is quantitatively described.The enhanced heat transfer degree of petal-ribbed tube compared to smooth tube is evaluated based on the performance evaluation coefficient(PEC).Results indicate that the PEC is higher than 1.2,and the buoyancy leads to the distorted temperature field and velocity field.The thickness of thermal boundary layer and velocity boundary layer are circumferential non-uniform,and the turbulence enhancement and heat transfer enhancement on the upper-right side of channel are most significant.With the increasing of operating pressure,both buoyancy and swirling flow weaken,and the coupling effect between buoyancy and swirling flow weakens,resulting in a weakening of circumferential non-uniform heat transfer in petal layers.The more petals there are,the weaker the buoyancy,the stronger the swirling flow,the weaker the coupling effect,and thus the more uniform the circumferential heat transfer.关键词
花瓣螺纹管/超临界/二氧化碳/增强换热/浮升力/旋流/二次流Key words
petal-ribbed tube/supercritical/carbon dioxide/enhanced heat transfer/buoyancy/swirling flow/secondary flow分类
能源科技引用本文复制引用
王彦红,黄帅岭,东明..水平花瓣螺纹管内超临界二氧化碳换热数值研究[J].大连理工大学学报,2026,66(1):48-56,9.基金项目
国家自然科学基金资助项目(51876031). （51876031）
