制冷技术2025，Vol.45Issue(4)：7-15,9.DOI:10.3969/j.issn.2095-4468.2025.04.102
底部带团簇微柱阵列结构的高宽深比微通道内流动沸腾实验研究
Experimental Study on Flow Boiling in High Aspect Ratio Microchannel with Chanel Bottom Covered by Cluster Micro-Pin Arrays
摘要
Abstract
Silicon-based high aspect ratio microchannels with channel bottom covered by clustered micro-pillar array structures is proposed and fabricated in this paper.The visualization study of flow boiling heat transfer is conducted using dielectric fluid HFE7100 as a working fluid.The results show that the convection heat transfer coefficient and pressure drop is increased with increasing heat flux at the stable flow boiling condition,and the flow pattern is changed from bubbly flow to churn flow.At the unstable flow boiling condition,the average wall temperature,pressure difference and their corresponding fluctuation periods are increased with the heat flux,accompanied by the periodical oscillation of flow patterns within bubbly flow,churn flow,and partial dry-out.The fluctuation period of wall temperatures is consistent with that of the flow pattern.Compared to the smooth microchannel,the heat flux transition to the flow boiling instability could be increased by about 15.8%for the microchannel with cluster micro-pin arrays,and the critical heat flux is increased by 14.8%.Comparing the onset of nucleate boiling at different mass flow rates,it is observed that confined bubbles could cover the entire microchannel at low mass flow rates,resulting in a rapid increase of the wall temperature at the downstream of the channel.At high mass flow rates,the required time transition to stable bubbly flow became shorter.Additionally,the nucleation sites primarily are appeared at the micro-pillar gap within the cluster structure.关键词
微通道/微柱阵列/流动沸腾不稳定性/表面传热系数Key words
Microchannel/Micro-pin array/Flow boiling instability/Surface heat transfer coefficient分类
通用工业技术引用本文复制引用
王志远,屈健..底部带团簇微柱阵列结构的高宽深比微通道内流动沸腾实验研究[J].制冷技术,2025,45(4):7-15,9.基金项目
国家自然科学基金(No.52276067). （No.52276067）
