鳍片管束分离器气固两相流动特性的PDA试验研究

<正>引言 惯性分离器与旋风分离器相比具有结构简单、易于布置、运行费用低等优点,因此广泛应用于循环流化床锅炉中。现有的许多惯性分离器都占据一个很大的水平烟道,使过热器布置不便,且对材质要求高,不能很好地满足大型化循环流化床锅炉的需要。浙江大学开发的新型鳍片管束撞击式分离器,其分离元件是由鳍片焊在锅炉中垂直布置的过热管束或对流管束上构成,从而将分离与强化传热相结合,分离性能试验研究表明其具有高效、低阻、结构紧凑、能强化传热、降低磨损等优点。为进一步研究鳍片管束分离器的分离、传热、磨损等特性,本文用三维粒子动态分析仪（3D-PDA）对其流动特性进行了冷态试验研究,并考虑了来流风速和鳍片结构对流动特性的影响。本文对测试结果进行了分析讨论,这些结果为鳍片管束分离器的优化设计以及气固分离机理的研究奠定了良好的基础。

EXPERIMENTAL STUDY OF TWO - PHASE FLOW INSIDE FINNED - TUBES SEPARATOR USING 3-D - PDA

By using a three-dimension particle dynamics analyzer (PDA), cold model experimental study on the characteristics of gas-solid two-phase flow around the finned-tube, the element of impact separator used in circulating fiuidized bed boiler (CFBB), was conducted. The distributions of velocity, turbulent intensity, particle size and solid concentration of gas-solid two-phase flow around finned tube were obtained. The effects of upstream velocity and finned tube structure on fluid characteristics were also considered. The measured results built a sound base for gas-solid separating mechanism research and structure optimization design of finned-tube separator.