化工学报2019，Vol.70Issue(12)：4590-4598,9.DOI:10.11949/0438-1157.20190377
PCHE内轴向导热对局部换热性能的影响研究
Investigations of axial conduction effect on local heat transfer performance in PCHE
摘要
Abstract
Numerical investigations of the axial conduction effect on the local heat transfer performance of the printed circuit heat exchanger (PCHE), which has straight channels and use supercritical pressure carbon dioxide (SCO2) as working fluid, were conducted under laminar conditions. Variations of local heat flux, heat transfer coefficient, heat effectiveness and entropy generation due to heat transfer in PCHEs were obtained under the conditions with or without axial conduction, when the wall thickness, diameter as well as the inlet temperature difference between the two sides get changed. Then, the effect of the axial heat conduction could be analyzed by comparing the results with/without the axial conduction. It was found that the axial conduction could greatly impact the temperature distributions in both solid and fluid domains and lead to significant changes to the convective heat transfer of SCO2 in PCHEs. When the axial conduction exists, the local heat flux variations get more even along the flow direction, and smaller heat transfer coefficient of the cold side as well as larger heat transfer coefficient of the hot side in the region of T<Tpc are also observed. The axial conduction would enlarge the peak heat effectiveness slightly and bring it to a lower bulk temperature. The heat transfer entropy production mainly occurs in the high temperature region, and the axial heat conduction can effectively reduce the local heat transfer entropy. Increasing the wall thickness and diameter can increase the influence of axial heat conduction, while increasing the inlet temperature difference, the influence of axial heat conduction does not change much.关键词
印刷电路板式换热器/超临界压力CO2/传热/轴向导热/层流/数值模拟Key words
printed circuit heat exchanger/ supercritical pressure carbon dioxide/ heat transfer/ axial conduction/laminar flow/ numerical simulation分类
能源科技引用本文复制引用
张海燕,郭江峰,淮秀兰,崔欣莹..PCHE内轴向导热对局部换热性能的影响研究[J].化工学报,2019,70(12):4590-4598,9.基金项目
国家自然科学基金项目(51676185) （51676185）
