A Thermoelectric Conversion System (TECS) with SCO2 as the circulating mass can effectively mitigate the fuel heat sink and electrical energy shortage problems of hypersonic vehicles. However, there is still a lack of research on the use of SCO2 in the harsh thermal conditions in scramjet. In this paper, the heat transfer mechanism of SCO2 in rectangular cooling tubes are numerically analyzed for the first time based on the actual working environment of scramjet. The effects of uneven heat flux (q) axial and circumferential allocations and circumferential and axial tilting of the tube are innovatively considered. Meanwhile, we analyze the heat transfer mechanism of SCO2 under different operating parameters. The results show that the uneven allocation of axial q can suppress the heat transfer deterioration (HTD), and the overall heat transfer coefficient (HTC) can be increased by 11.68 % when the q allocation is Gaussian. The increase of the tube inclination angle can improve its heat transfer performance, and the local HTC can be increased by up to 5.64 % when θ2 = 180°.Increasing the mass flow rate (G) and inlet temperature (Tin) can increase the overall HTC of the tube. This paper can provide guidance for the design and improvement of TECS.

中文翻译：

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大质量流量和热通量条件下非均匀加热矩形冷却管中SCO2的传热特性


以SCO2为循环质量的热电转换系统（TECS）可以有效缓解高超声速飞行器的燃料散热和电能短缺问题。然而，对于SCO2在超燃冲压发动机恶劣热条件下的应用仍缺乏研究。本文结合超燃冲压发动机的实际工作环境，首次对矩形冷却管内SCO2的传热机理进行了数值分析。创新性地考虑了热通量（q）轴向和周向分配不均匀以及管子周向和轴向倾斜的影响。同时，我们分析了SCO2在不同运行参数下的传热机理。结果表明，轴向q的不均匀分配可以抑制传热恶化（HTD），当q分配为高斯分布时，总传热系数（HTC）可提高11.68%。管倾角的增大可以改善其传热性能，当θ2=180°时，局部HTC可提高最多5.64%。提高质量流量（G）和入口温度（Tin）可以提高整体传热系数。 HTC的管子。本文可为TECS的设计和改进提供指导。