摘要
为了探究相分离结构对微细通道流动沸腾传热性能和均温性的影响,对三种相分离孔数(10孔N1型、20孔N2型、30孔N3型)和三种布置位置(中下游A型、上下游B型、上中下游C型)开展了研究。实验采用乙醇作为工质,在热通量15.05~124.89 kW/m^(2)、工质入口温度40℃、质量流率102.50 kg/(m^(2)·s)条件下,对2 mm×2 mm矩形逆流微细通道进行流动沸腾实验,通过脉动压力实现气相分离。引入强化传热因子、沿程壁温分布、壁面平均温度和温度标准差等参数分析相分离结构的影响。结果表明,跨膜压力一定时,相分离孔数为20时传热系数最大,孔数增加至30对传热提升有限。与无相分离工况相比,相分离结构使传热强化因子最大达1.92,沿程壁温标准差最大降低44%。这表明,相分离微细通道有效提升了传热效率和均温性。
Phase separation structure microchannels have attracted considerable attention due to their high heat transfer efficiency and minimal pressure fluctuations.The effect of phase separation structure on the heat transfer property and temperature uniformity of microchannel was studied,this paper conducts research on three types of phase separation hole counts:10-hole N1 type,20-hole N2 type and 30-hole N3 type,as well as three types of phase separation arrangement positions:midstream and downstream(Type A),upstream and downstream(Type B),and upstream,midstream,and downstream(Type C).Ethanol is used as the working fluid,and flow boiling experiments are conducted in a rectangular counterflow microchannel with a cross-section of 2 mm×2 mm under conditions of heat flux density ranging from 15.05 to 124.89 kW/m^(2),inlet temperature of 40℃,and mass flow rate of 102.50 kg/(m^(2)·s).Pulsating pressure is applied to the forward channel to achieve gas phase separation.The effects of the phase separation structure were analyzed by introducing parameters such as the heat transfer enhancement factor,along-line wall temperature distribution,average wall temperature,and temperature standard deviation.The research results indicate that,at a constant transmembrane pressure,the heat transfer coefficient reaches its maximum when the number of phase separation holes is 20,and further increasing the number to 30 does not significantly enhance the heat transfer effect.In comparison with the non-phase-separation operational conditions,the maximum heat transfer enhancement factor in the microchannel with phase separation structures reaches 1.92,while the maximum standard deviation of two-phase wall temperature along the path is reduced by 44%.This suggests that phase separation microchannels can effectively improve the heat transfer efficiency and temperature uniformity in microchannels.
作者
罗小平
肖岚
张嘉宇
LUO Xiaoping;XIAO Lan;ZHANG Jiayu(School of Mechanical and Automotive Engineering,South China University of Technology,Guangzhou 510640,Guangdong,China)
出处
《化工学报》
北大核心
2025年第11期5877-5889,共13页
CIESC Journal
基金
国家自然科学基金项目(22178118)。
关键词
脉动压力
相分离结构
逆流
微细通道
强化传热
均温性
pulsating pressure
phase separation structure
counterflow
microchannels
heat transfer enhancement
temperature uniformity
