Abstract A numerical study of the forced convection of a two-dimensional laminar air flow through a rectangular pipe with a shoulder is presented. The profiles and contours of velocity and temperature were analyzed in detail. The effects of the location of this shoulder on the insulation and on the absorber, and its height on the variations of the temperature and the velocity at the exit of the collector were also studied and compared with the case without shoulder, for a flow rate varying between 20 and 80 m3/h. The results show that the use of a shoulder placed on the insulator or on the absorber contributes to increasing the dynamic and thermal performance of the flow compared to the simple case; an average temperature gain of 25.52 °C at 56.6 °C is obtained for the low and high flow rates, respectively. The study also revealed that the use of the largest height h3 rated absorber can significantly increase the velocity (of the order of 222%) compared to the simple case. In addition, this location allows to direct the flow at the entrance of the drying chamber downwards, which leads to better evacuation of moist air at the chimney outlet.

中文翻译：

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肩部的存在对飞机太阳能集热器中层流的热和动力学结构的影响

摘要 提出了二维层流气流通过带台肩矩形管强制对流的数值研究。详细分析了速度和温度的轮廓和轮廓。还研究了这个肩部的位置对绝缘体和吸收器的影响，以及它的高度对收集器出口处温度和速度变化的影响，并与没有肩部的情况进行了比较，对于不同的流速20 至 80 立方米/小时。结果表明，与简单情况相比，使用放置在绝缘体或吸收器上的肩部有助于提高流动的动态和热性能；对于低流速和高流速，分别在 56.6 °C 和 56.6 °C 下获得了 25.52 °C 的平均温度增益。该研究还表明，与简单情况相比，使用最大高度 h3 额定吸收器可以显着增加速度（大约 222%）。此外，该位置允许将干燥室入口处的气流向下引导，从而更好地排出烟囱出口处的潮湿空气。