Heat transfer enhancement due to flapping flags in a heated duct flow is studied using three-dimensional (3D) fully coupled fluid–structure–thermal simulations. Following prior work, which was limited to two-dimensional models, we examine the mechanisms and the heat transfer performance for a more realistic, 3D model of a flag in a rectangular duct heat exchanger. We then examine the role of the flag aspect-ratio and spanwise confinement, which are key design parameters for this device. We find that the narrow flags do not exhibit sufficiently energetic flapping to generate any meaningful heat transfer enhancement. We also find that the wide flags significantly increase heat flux and an increase in the width of the flag can further increase the thermal enhancement factor.

中文翻译：

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由于飘动的旗帜在层流换热器中的传热增强

使用三维 (3D) 完全耦合的流体-结构-热模拟研究了由于加热管道流中的飘动标志引起的传热增强。继之前仅限于二维模型的工作之后，我们检查了矩形管道换热器中更逼真的 3D 旗形模型的机制和传热性能。然后我们检查标志纵横比和展向限制的作用，这是该设备的关键设计参数。我们发现窄旗没有表现出足够的能量扑动以产生任何有意义的传热增强。我们还发现宽旗帜显着增加了热通量，并且旗帜宽度的增加可以进一步增加热增强因子。