CIESC Journal ›› 2014, Vol. 65 ›› Issue (12): 4749-4754.DOI: 10.3969/j.issn.0438-1157.2014.12.014

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Direct contact condensation of steam bubbles with non-condensable gas

QU Xiaohang1, TIAN Maocheng1, ZHANG Guanmin1, LUO Lincong2   

  1. 1. School of Energy and Power Engineering, Shandong University, Jinan 250061, Shandong, China;
    2. National Urban Energy Measurement Center, Chongqing Academy of Metrology and Quality Inspection, Chongqing 401123, China
  • Received:2014-06-03 Revised:2014-08-11 Online:2014-12-05 Published:2014-12-05
  • Supported by:

    supported by Shandong Province Key Scientific and Technological Project (2008GG10007009) and the Science and Technology Development Planning of Shandong Province (2012GGX10421).

含不凝气体蒸汽泡直接接触冷凝

屈晓航1, 田茂诚1, 张冠敏1, 罗林聪2   

  1. 1. 山东大学能源与动力工程学院, 山东 济南 250061;
    2. 重庆计量质量检测研究院国家城市能源计量中心, 重庆 401123
  • 通讯作者: 田茂诚
  • 基金资助:

    山东省科技攻关项目(2008GG10007009);山东科技发展计划项目(2012GGX10421).

Abstract: The condensation behavior and heat transfer characteristics of steam bubbles with air were investigated by visual experiments, with steam mass fraction between 0.5 and 0.8. Bubbles of gas mixture were injected into cool water at two different temperatures through nozzles of diameter 1.5 and 3 mm. The condensing processes of bubbles were recorded by high speed camera and the thermodynamic parameters of bubbles were obtained by the variation of bubble volumes, from which the condensing heat transfer coefficients were calculated. The results show that the bubble deforms continuously when it condenses and a hollow forms in the middle of the bubble at the beginning of the condensing process. The condensing heat transfer coefficient decreases as cool water temperature decreases and bubble volume increases, while it is not affected by the nozzle diameter. The condensing heat transfer is deteriorated by the noncondensing gas. A correlation to predict the heat transfer coefficients is established using all the 65 data obtained in this experiment.

Key words: bubble condensing, non-condensable gas, heat transfer coefficient, visual experiment

摘要: 通过可视化实验研究了含空气蒸汽泡的冷凝行为和传热特性,气泡中蒸汽质量含量在0.5~0.8之间.在两种不同的过冷水温度下,混合气体气泡分别由直径1.5 mm和3 mm的喷嘴以不同的速度喷入静止的过冷水空间中.通过高速摄像机记录气泡冷凝过程,通过气泡体积变化状况计算气泡热力学参数,进而计算气泡的冷凝传热系数.结果表明,气泡在冷凝过程中不断变形,且在冷凝开始时,气泡出现中空现象;冷水温度越低,冷凝传热系数越低;气泡体积越大,冷凝传热系数越低;喷嘴直径对冷凝传热影响不明显;不凝气体的加入恶化了冷凝传热.对实验中65个气泡传热系数的数值进行了拟合,获得了传热系数关联式.

关键词: 气泡冷凝, 不凝气体, 传热系数, 可视化实验

CLC Number: