| 摘要: |
| 为了探究开口结构对微肋阵矩形通道沸腾换热的影响，本文对开口水滴形微肋阵通道流动沸腾换热性能进行可视化实验，并与水滴形微肋阵通道流动沸腾换热性能对比，借助高速摄像仪对通道内不同流量下汽泡的流动和生长过程进行记录与分析。以去离子水为工质，入口温度为30 ℃，流量范围为0.2~7.2 kg/h，加热电压为60 V，拍摄频率为500 fps。实验结果表明：微肋阵的开口结构会影响流动特性；开口结构增加了换热面积，有利于汽化核心的形成，有利于换热。在较低和较高雷诺数下，开口水滴形微肋阵的对流换热优于水滴形微肋阵；开口水滴形通道II区和III区域内汽泡的等待时间和生长时间均随雷诺数的增大而逐渐增大，且汽泡的生长时间大于等待时间，此外，针肋末端II区域的等待时间和生长时间均比III区域的更短。 |
| 关键词: 微肋阵矩形通道 流动沸腾 开口水滴形 汽泡等待时间 汽泡生长时间 |
| DOI： |
| 投稿时间：2021-04-28 修订日期：2021-08-31
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| 基金项目: |
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| Effect of Open Structure on Boiling Heat Transfer and Bubble Dynamic Growth Characteristics of Micro Fin Array |
| Sun Ruirui,Zhang Jing,Hua Junye,Zhao Xiaobao,Qin Luwen |
| (School of Energy and Mechanical Engineering, Nanjing Normal University;Technology Engineering Laboratory of Energy System Process Transformation and Emission Reduction in Jiangsu Province) |
| Abstract: |
| To explore the effect of the open structure on the boiling heat transfer of a micro-ribbed rectangular channel, a visual experimental study was conducted on the flow boiling heat transfer performance of open drop-shaped micro-rib channels and compared with the flow boiling heat transfer performance of a water droplet microchannel. At the same time, the flow and growth processes of bubbles under different flow rates in the channel were recorded and analyzed using a high-speed camera. Using deionized water as the working fluid, the inlet temperature was set at 30 °C, with a flow rate of 0.2–7.2 kg/h, heating voltage of 60 V, and shooting frequency of 500 fps. The experimental results show that the opening structure of the micro-fin array affects the flow characteristics. The open structure increases the heat transfer area, which is beneficial for the formation of the vaporization core and heat transfer. At lower and higher Re, the convection heat transfer of the unclosed droplet-shaped micro-fin array is better than that of the water-droplet-shaped micro-fin array. The waiting time and growth time of bubbles in microchannels II and III increase with an increase in Re, and the bubble growth time is greater than the waiting time. In addition, the waiting and growth times of region II were shorter than those of region III. |
| Key words: micro-ribbed rectangular channel flow boiling unclosed drop shape bubble waiting time bubble growth time |
