ABSTRACT The effect of helix angle and pitch ratio of helical surface disc turbulators on the thermal performance of double pipe heat exchanger are discussed in this study. Tests are performed with air as working fluid for different pitch ratios, numerous helix angles, and various Reynolds number. Water and air are allowed to flow along inner tube and through annulus, respectively. In each case, the thermal enhancement factor is observed to be higher than unit value. Smallest pitch ratio and highest helix angle yield highest thermo-hydraulic performance of 1.39 at Re = 3,500. Correlations are developed for various parameters.

中文翻译：

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螺旋面盘式湍流器对双管水气换热器热摩擦特性的影响

摘要 本研究讨论了螺旋面盘式湍流器的螺旋角和螺距比对双管换热器热性能的影响。针对不同螺距比、多种螺旋角和各种雷诺数，使用空气作为工作流体进行测试。允许水和空气分别沿内管和通过环形空间流动。在每种情况下，观察到的热增强因子都高于单位值。在 Re = 3,500 时，最小螺距比和最大螺旋角产生 1.39 的最高热液压性能。为各种参数开发了相关性。