相分离结构与电场协同作用下微细通道流动沸腾传热
Study on flow boiling heat transfer in microchannel under synergistic effects of phase separation structure and electric fields
罗小平 1李晓婷 1杨书斌1
作者信息
- 1. 华南理工大学 机械与汽车工程学院,广东 广州 510640
- 折叠
摘要
为研究相分离结构与电场协同作用下微细通道内流动沸腾传热特性,以质量分数为 30%的甘油水溶液为试验工质,在入口温度为 70℃、质量流率为 121.25 kg·m-2·s-1、热流密度为 90.31～151.23 kW·m-2 的工况下,针对 0、800、1600 V不均匀电场,在截面为 2 mm×2 mm的不同相分离结构逆流微细通道内开展流动沸腾试验,研究不同电场和不同相分离结构协同作用下微细通道内局部饱和沸腾传热系数及影响规律,结合可视化结果分析相分离结构与电场协同作用下受限气泡长径比变化以及强化机理.利用平均传热综合性能评价指标评估相分离结构与电场协同作用下微细通道的传热综合性能.结果表明,相较于无电场无相分离结构,相分离结构与电场协同作用下,局部饱和沸腾传热系数和受限气泡单位时间长径比变化比率ζ分别最大提高了 61.22%、605.5%;平均传热综合性能评价指标最高可达 1.50.
Abstract
In order to study the flow boiling heat transfer characteristics in microchannels under synergistic effects of phase separation structure and electric fields,30%glycerol aqueous solution was used as the working fluid under conditions of inlet temperature 70℃,mass flow rate 121.25 kg·m-2·s-1,heat flow density 90.31-151.23 kW·m-2 and non-uniform electric fields of 0,800 and 1600 V.Flow boiling tests were carried out in countercurrent microchannels with different phase separation structures(cross-section of 2 mm×2 mm)to study local saturated boiling heat transfer coefficients and mechanism under the synergistic effect of electric fields and phase separation structures.The change of length diameter ratios of confined bubbles and the strengthening mechanism based on the visual results under the synergistic effects were analyzed.The average heat transfer performance evaluation index was used to evaluate the heat transfer performance of microchannels under the synergetic effect.The results show that compared with the non electric field and non phase separation structure,the maximum local saturated boiling heat transfer coefficient and the maximum change ratio of the length diameter ratio of confined bubbles per unit time ζ increased by 61.22%and 605.5%respectively,the average comprehensive performance evaluation index of heat transfer can reach 1.50.
关键词
微细通道/相分离结构/电场/流动沸腾/可视化Key words
microchannel/phase separation structure/electric field/flow boiling/visualization引用本文复制引用
基金项目
国家自然科学基金(22178118)
广东省自然科学基金(2019A1515011053)
出版年
2024
国家科技期刊平台
NSTL
万方数据