文档介绍：中国工程热物理学会传热传质学
学术会议论文编号:123354
单面加热垂直矩形窄通道流动沸腾换热理论和实验研究
黄理浩陶乐仁芮胜军郑志皋薛维超高立博
(上海理工大学制冷及低温工程研究所上海 200093)
(Tel:**********,E-mail:huanglihao1208@)
摘要建立单面加热垂直矩形窄通道流动沸腾换热实验装置,针对截面为250mm×5 mm的竖直矩形窄缝通道,对水流动沸腾换热特性进行实验研究。通过实验分析可知:①流体处于泡状流时,主导机理为饱和核沸腾,其局部换热系数存在一个最大值;②质量流量对通道出口顶端测点局部换热系数的影响主要体现在两个方面:流量的增大会使流动流体的紊流度增加,加强了液膜的对流换热;流动流体流速的增大会减小液膜的厚度,增强了液膜的导热和蒸发换热;③当所取测点靠近汽化核心处时,流量增大会使过冷液体预热不充分直接进入饱和主流液体中,汽化核心产生的汽泡遇到过冷液体被冷凝而湮灭,导致换热系数的降低。
关键词窄通道;饱和核沸腾;液膜;汽化核心
中图分类号:TK124 文献标识码:A
Theory and Experimental Studies on Flow Boiling Heat Transfer in Single-side Heated Vertical Rectangular Narrow Channel
Huang Li-hao Tao Le-ren Rui Sheng-jun Zheng Zhi-gao Xue Wei-chao Gao Li-bo
(Institute of Refrigeration and Cryogenic Engineering of University of Shanghai for Science and Technology Shanghai 200093)
Abstract: A single-side heating apparatus is set up to study the flow boiling and heat transfer in vertical narrow rectangular channel, experiment research on flow boiling and heat transfer characteristics in a vertical narrow rectangular channel with the section of 250mm×5 mm is carried out. According to the experimental analysis: ①when the fluid is in bubbly flow, the dominant mechanism is Saturated nucleate boiling, and the local heat transfer coefficient exists a maximum; ②two main influences for local heat transfer coefficient in the channel top points: Increasing mass flux will make the fl