CIESC Journal ›› 2020, Vol. 71 ›› Issue (4): 1502-1509.DOI: 10.11949/0438-1157.20190982

• Fluid dynamics and transport phenomena • Previous Articles     Next Articles

Experimental investigation on flow boiling heat transfer in sinusoidal wavy copper microchannels

Xinyu YAO(),Xiao CHENG,Han WANG,Hong SHEN,Huiying WU,Zhenyu LIU()   

  1. School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
  • Received:2019-08-30 Revised:2020-01-04 Online:2020-04-05 Published:2020-04-05
  • Contact: Zhenyu LIU

铜基正弦波微通道内流动沸腾传热特性试验研究

姚鑫宇(),程潇,王晗,沈洪,吴慧英,刘振宇()   

  1. 上海交通大学机械与动力工程学院,200240,上海 200240
  • 通讯作者: 刘振宇
  • 作者简介:姚鑫宇(1994—),男,硕士研究生, yaoxinyu@sjtu.edu.cn
  • 基金资助:
    国家自然科学基金项目(51676124);上海市国际科技合作基金项目(18160743900)

Abstract:

In this work, the sinusoidal wavy (SW) copper microchannel with triangular cross section is manufactured with the ultrafast laser micromachining approach, which is a promising technique for the fabrication of metallic microchannels due to its high accuracy and high processing efficiency. The experimental setup is established to study flow boiling heat transfer process in SW microchannel and the deionized water was utilized as the working fluid. The flow boiling phenomena in SW microchannel are experimentally investigated under different mass and heat fluxes. Based on obtained experimental results (temperature/pressure data and flow pattern images), it is found that the local heat transfer coefficient experiences a sharp increase and then decreases to a stable value with the increase of outlet vapor quality. The SW microchannel achieves a 127.7% increase of heat transfer coefficient and a 14.4% increase of pressure drop compared to the straight one. The wavy channel structure can significantly inhibit the instability in flow boiling. The dominant heat transfer mechanism gradually changes from nucleate boiling to thin film evaporation.

Key words: sinusoidal wavy microchannel, ultrafast laser micromachining, flow boiling, flow instability

摘要:

基于超快激光技术加工铜基正弦波弯曲型微通道,以去离子水为流动工质,在不同质量流量和热通量条件下,对弯曲型微通道内流动沸腾特性进行试验研究。基于温度/压力数据和流动可视化结果,发现通道传热系数随出口干度增大,呈迅速增大后减小并趋于稳定趋势,正弦波微通道相较直微通道具有更好的换热性能,传热系数最大提高127.7%,压降仅增加14.4%。波状通道结构能明显抑制流动沸腾中不稳定现象发生。通过可视化试验发现,随热通量增大,流型经历泡状流-弹状流-环状流的转变,换热主导机制由核态沸腾逐渐过渡到薄液膜蒸发。

关键词: 正弦波微通道, 超快激光微加工, 流动沸腾, 流动不稳定性

CLC Number: