余热利用是实现“碳达峰”与“碳中和”双重目标的重要举措。基于热电热效应的温差发电技术可直接将热能转化为电能，因其具有无污染、耐候性强、维护方便等优点，可对回收难度较大的高温余热进行有效利用。高温余热最突出的特点是其在流动过程中自身携带的剩余热量占比较大，因此提升此部分热量的利用率已成为该技术发展的一个重要方向。本文设计了一种针对高温烟气的圆筒式温差发电装置，并搭建了实验平台，重点分析了不同集热器类型和集热器结构参数对装置换热效果和输出特性的影响，旨在通过增强换热提升装置的热电性能，主要研究工作如下：

（1）系统阐述了热电效应的相关理论，确定了温差发电装置性能优劣的评价标准，建立了温差发电系统的传热模型，理论分析了装置热端、冷端以及热电模块之间的传热流程，依据热阻网络图及传热方式对集成后温差发电系统的热量转换进行理论计算。

（2）建立了翅片式集热器和分流桶式集热器的强化换热模型，对不同类型集热器进行仿真分析，结果表明：增加翅片导热面积对装置换热效果的提升有限，热电模块的冷热端温差沿烟气流向逐渐降低；分流桶式集热器可以增强烟气的湍流强度，改变了烟气沿流向热能耗散过程中热电模块温差逐渐降低的缺点，其结构参数变化对换热效果的提升较为灵活。

（3）数值模拟研究了分流桶式集热器结构参数对装置性能的影响，结果表明：分流桶端盖未开孔下热电模块冷热端温度、温差显著大于端盖开孔结构。分流孔直径和分流桶直径对热电模块冷热端温差和温度分布均匀性的敏感度较高，分流孔直径最小（2mm）且分流桶直径适中（130mm）条件下装置的换热性能较好。分流孔排间距和分流孔数量对排气压降的敏感度较大，排间距为10mm、每排分流孔数量为24时装置的排气压降较低。分流桶直径最大时（140mm），渐变分流孔直径下（2.9mm-2.5mm-2.2mm-2.0mm），装置的换热性能进一步提高，排气压降也相对减小。

（4）实验测试与仿真结果的对比分析验证了分流桶式集热器强化换热的有效性，实验结果表明：换热较优的分流桶结构下装置的发电性能也较强。分流桶直径为130mm，分流孔直径为2mm时热电模块的平均温差为138℃，装置的最大输出功率为85.4W，热电转换效率为2.9%；分流桶直径为140mm时，分流孔渐变直径下（2.9mm-2.5mm-2.2mm-2.0mm）热电模块的平均温差进一步升高，为151℃，最大输出功率达到89.1W，热电转换效率提升至3.2%。

The recycling of waste heat is an important measure to achieve the dual goals of "carbon peak" and "carbon neutrality". The technology of thermoelectric power generation based on thermoelectric conversion effect which can directly convert heat energy into electric energy. Because of its advantages of no pollution, strong weather resistance, convenient maintenance and so on, the high temperature waste heat which is difficult to collect can be effectively utilized. The most prominent characteristic of high temperature waste heat is that the residual heat carried by itself in the flow process accounts for a large proportion. Therefore, improving the utilization rate of this part of heat has become an important direction for the development of this technology. In this paper, the device of a cylindrical thermoelectric power generation for high temperature flue gas is designed, and the experimental platform is built. The influence of different collector types and collector structure parameters on the effect with heat transfer and output characteristics of the device is analyzed, aiming to improve the thermoelectric performance of the device by enhancing the heat transfer. The main work of research is as follows:

(1) The theory of thermoelectric conversion effect is expounded systematically and the evaluation standard of the performance about the device of thermoelectric power generation is determined. The model of heat transfer on the thermoelectric power generation system is established, the heat transfer process between hot end, cold end and thermoelectric module of thermoelectric power generation is analyzed theoretically. According to the thermal resistance network diagram and heat transfer mode, the heat transfer of integrated thermal power generation system is calculated theoretically.

(2) The enhanced heat transfer models of finned collector and shunt bucket collector are established, and different types of collectors are simulated and analyzed. The results show that: Increasing the heat transfer area of fins has limited improvement on the heat transfer effect, and the temperature difference between hot and cold ends of the thermoelectric module decreases gradually along the flue gas flow direction. The shunt bucket collector can increase the turbulence intensity of the flue gas and change the disadvantage that the temperature difference of the flue gas decreases gradually in the heat dissipation process along the flow direction. The change of its structural parameters is more flexible to improve the heat transfer effect.

(3) The influence of structure parameters on the performance of the shunt bucket collector is studied by numerical simulation. The results show that the temperature and temperature difference of the hot and cold end of the thermoelectric modules under the end cover without holes of the shunt bucket are significantly greater than the open structure of the end cover. The diameter of the shunt hole and the diameter of the shunt bucket have high sensitivity to the temperature difference and the uniformity of temperature distribution at the hot and cold end of the thermoelectric modules, and the heat transfer performance of the device is better under the condition that the shunt hole diameter is the smallest (2mm) and the diameter of the shunt bucket is moderate (130mm). The spacing between the shunt holes and the number of shunt holes are more sensitive to pressure drop of exhaust, and the pressure drop is lower when the spacing between the rows is 10mm and the number of shunt holes per row is 24. When the diameter of the diverter bucket is the largest (140mm), under the diameter of the gradient shunt hole (2.9mm-2.5mm-2.2mm-2.0mm), the heat transfer performance of the device is further improved, and the exhaust pressure drop is also reduced.

(4) The comparison between the experimental test and the simulation results verifies the effectiveness of the shunt bucket collector in enhancing heat transfer. The experimental results show that the device with better heat transfer of shunt bucket has stronger power generation performance. When the diameter of the shunt bucket is 130mm and the diameter of the shunt hole is 2mm, the average temperature difference of the thermoelectric modules is 138℃, the maximum output power of the system is 85.4W, and the efficiency of thermoelectric conversion is 2.9%. When the diameter of the shunt bucket is 140mm, the average temperature difference of the thermoelectric modules further increases to 151℃ under the gradient diameter of the shunt hole (2.9mm-2.2mm-2.2mm-2.0mm), the maximum output power reaches 89.1W, and the efficiency of thermoelectric conversion rises to 3.2%.

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