摘要
表面微结构化是强化沸腾传热的重要手段,研究微结构尺寸对沸腾传热特性的影响规律意义重大。本文采用选择性激光熔化技术(SLM)制备了不同宽度的槽道结构试样,并对其进行了常压下池沸腾传热特性实验研究。结果表明,相比于光滑铜面,槽长2.3mm,槽宽0.5~2.3mm槽道结构的传热系数(HTC)与临界热通量(CHF)均有显著提升。槽道结构的CHF随着槽道宽度的增大先增加后减小,HTC随着槽道宽度的增大而减小。槽道宽度为0.9mm时CHF达到最大值331.5W/cm^(2),为光滑铜面的3倍,同时HTC为光滑表面的1.7倍。较小的槽道宽度增加了试样的传热面积,限制了气泡脱离直径进而增加气泡的脱离频率,是HTC提升的关键因素;而槽道内气液流动阻力限制与水动力不稳定性,是槽道结构CHF提升的关键控制因素。
Surface microstructure is an important means to enhance boiling heat transfer,and it is significant to study the influence of microstructure size on boiling heat transfer characteristics.In this paper,selective laser melting(SLM)technology was used to fabricate channel structure samples with different widths,and the experimental study of pool boiling heat transfer characteristics under atmospheric pressure was carried out.The results showed that compared with the smooth copper surface,the heat transfer coefficient(HTC)and critical heat flux(CHF)of the groove structure with the groove length of 2.3mm and the groove width of 0.5-2.3mm were significantly improved.CHF of channel structure first increased and then decreased with the increase of channel width,and HTC decreases with the increase of channel width.CHF reached a maximum of 331.5W/cm^(2) at a channel width of 0.9mm,which was 3 times that of a smooth copper surface,and the HTC was 1.7 times that of the smooth surface.Smaller channel widths increased the heat transfer area of the specimen,limited the bubble departure diameter,and then increased the bubble separation frequency,which was a key factor for HTC enhancement.The gas-liquid flow resistance limitation and hydrodynamic instability in the channel were the key control factors for CHF enhancement in channel structure.
作者
刘厚励
顾中浩
阳康
张莉
LIU Houli;GU Zhonghao;YANG Kang;ZHANG Li(School of Mechanical and Power Engineering,East China University of Science and Technology,Shanghai 200237,China)
出处
《化工进展》
EI
CAS
CSCD
北大核心
2023年第5期2282-2288,共7页
Chemical Industry and Engineering Progress
基金
国家自然科学基金(51776074)。
关键词
传热
池沸腾
相变
3D打印
气液两相流
槽道结构
heat transfer
pool boiling
phase change
3D printing
gas-liquid flow
groove structure
作者简介
第一作者:刘厚励(1990-),男,博士研究生,研究方向为多孔结构强化沸腾传热。E-mail:flyli5@126.com;通信作者:张莉,教授,博士生导师,研究方向为强化相变传热技术。E-mail:lzhang@ecust.edu.cn。
