多微通道内两相流动阻力特性及气泡行为

发布时间：2018-01-31 00:23

本文关键词： 微通道两相流可视化压降 OFI点气泡动力学　出处：《化工学报》2017年S1期 　论文类型：期刊论文

【摘要】：采用去离子水作为实验工质,对14条水力直径为187.5μm的平行矩形微通道内两相流动阻力特性及气泡行为进行可视化实验。研究发现,当质量流速一定时,随着热通量增大,汽相逐渐增多,平行多微通道内压降相应增加;当热通量一定时,随着质量流速减小,压降出现先减小后增大的趋势,该曲线中的最低点被认为是静态流动不稳定性起始点(OFI点)。结合可视化图像并利用气泡动力学理论对4种不同的汽相行为特征进行分析,发现汽核受限、倒流等堵塞流道现象的出现导致系统阻力增大,压降增加。通过压降实验值与KimMudawar关系式在不同质量流速下进行比较发现,KimMudawar关系式仅能对本实验压降变化趋势进行预估,而无法对压降数值进行有效预测。
[Abstract]:Using deionized water as experimental medium, the flow resistance characteristics and bubble behavior of 14 parallel rectangular microchannels with hydraulic diameter of 187.5 渭 m were studied. When the mass flow rate is constant, the vapor phase increases gradually with the increase of heat flux, and the pressure drop in parallel multi-microchannels increases accordingly. When the heat flux is constant, the pressure drop decreases first and then increases with the decrease of mass flow rate. The lowest point of the curve is considered as the OFI point of static flow instability. Combined with visual images and using bubble dynamics theory, four different characteristics of vapor phase behavior are analyzed. It is found that the system resistance increases and the pressure drop increases due to the phenomenon of blocked flow channel such as confined steam core and reverse flow. The comparison between the pressure drop experimental value and the KimMudawar formula at different mass velocity is carried out. The KimMudawar relation can only predict the variation trend of pressure drop in this experiment, but can not predict the pressure drop value effectively.
【作者单位】：重庆大学动力工程学院;中国航天科技集团公司七三0四厂;河南中烟漯河卷烟厂;
【基金】：国家自然科学基金面上项目(51376201,51676020)~~
【分类号】：O359
【正文快照】： 3河南中烟漯河卷烟厂,河南漯河462000)Characteristics of two-phase flow resistance and bubble behaviorin microchannelsYAN Rungang1,2,PAN Liangming1,HE Hui 1,HUANG Haojie1,LI Pengfei 3(1 School of Power Engineering,Chongqing University,Chongqing400044,China;

【相似文献】