| 摘要: |
| 为研究复杂传热条件下，低温非热平衡圆柱表面温度分布特性及相关控制手段，本文以单纯顶部送风为基础，建立了附加局部送风、附加辐射屏两种传热条件下的非热平衡圆柱体的传热模型，通过数值模拟方法分析了该柱体的径向温度梯度、体温度不均匀度、面温度不均匀度等温度特性，并通过实验验证了数值模拟结果的准确性。在此基础上定量分析了不同传热方式和运行参数对温度特性的影响规律，从传热方式、结构设计、运行参数三个角度，提供了控制柱体温度特性的方案。结果发现:相比于只有单纯顶部送风，设置局部喷口送风可使柱体平均温度的降幅提升5.1％，柱体温度不均匀度降幅提升38.3％，同时降低了柱体面温度不均匀度，并将柱体温度梯度控制在近导热面侧；附加低温辐射屏后，对流和辐射的耦合传热可使柱体平均温度降幅减少23％，柱体温度不均匀度降幅提升57.5％，同时降低了柱体面温度不均匀度。 |
| 关键词: 对流传热 辐射传热 耦合作用 温度均匀度 |
| DOI： |
| 投稿时间：2020-03-06 修订日期：2020-06-22
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| 基金项目:国家自然科学基金(51936006)资助项目。 |
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| Numerical and Experimental Study of the Temperature Distribution Characteristics of a Cryogenic Non-thermal Equilibrium Cylinder |
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Du Yicen, Cheng Ruijie, Wu Shize, Cai Aifeng, Wu Jingyi, Yang Guang
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| (Institute of Refrigeration and Cryogenics,Shanghai Jiao Tong University) |
| Abstract: |
| To study the surface temperature distribution characteristics and related control methods of cryogenic non-thermal equilibrium cylinders under complex heat transfer conditions, this study establishes two models of heat transfer enhancement methods appended to pure top ventilation: an additional local nozzle air supply and a radiation screen. The temperature characteristics, such as radial temperature gradient, body temperature non-uniformity, and surface temperature non-uniformity of the cylinder, are analyzed by numerical simulation methods. The accuracy of the numerical simulation results was verified by experiments. On this basis, the influence of different heat transfer methods and operating parameters was quantitatively analyzed. The results show that, compared with simple top ventilation, the local nozzle air supply can increase the average temperature decrease of the cylinder by 5.1%, the temperature non-uniformity of the cylinder can be increased by 38.3%, and the temperature unevenness of the cylinder surface can be reduced. The temperature gradient of the cylinder was controlled on the side near the heat-conducting surface. With the addition of a cryogenic radiation screen, the coupled heat transfer of convection and radiation can reduce the average temperature decrease of the cylinder by 2.3%, increase the temperature unevenness of the cylinder by 57.5%, and reduce the temperature unevenness of the cylinder surface. |
| Key words: convective heat transfer radiative heat transfer coupling effect temperature uniformity |
