ABSTRACT Heat transfer performance and flow characteristics in the Helically Coiled-Twisted Flat Tube (HCTFT) are studied by a numerical simulation. According to the results, the secondary flow caused by the twisted structure destroys the velocity boundary layer, decreases the thermal-conduction resistance, increase the turbulence kinetic energy. The heat transfer performance of HCTFT is greater than Helically Coiled Smooth Tube (HCST). In the range of research, the Performance Evaluation Criterion (PEC) could achieve the maximum value 1.21, 1.21, 1.35 and 1.23, respectively. New correlations of heat transfer performance and flow characteristics in the tube side are developed.

中文翻译：

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螺旋盘绕扁管传热性能及流动特性研究

摘要 通过数值模拟研究了螺旋盘绕扭曲扁平管 (HCTFT) 的传热性能和流动特性。结果表明，扭曲结构引起的二次流破坏了速度边界层，降低了热传导阻力，增加了湍流动能。HCTFT 的传热性能优于螺旋盘绕光滑管 (HCST)。在研究范围内，绩效评价标准（PEC）分别达到最大值1.21、1.21、1.35和1.23。开发了管侧传热性能和流动特性的新关联。