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通过实验方法测试了横纹管和光管的传热与阻力性能,拟合出了所测的参数范围内横纹管和光管传热和阻力实验关联式。为了研究横纹管结构对管内平均传热系数的影响,探讨了其强化传热机制,采用数值模拟的方法比较了对强化传热起关键作用的湍流强度、热边界层厚度、协同角及局部努谢尔数Nu的变化规律。分析结果表明,横纹管传热性能优于光管的原因在于边界层薄且扰动强,而且横纹管强有较好的场协同作用,全场速度和温度梯度之间的平均夹角减小。
The heat transfer and resistance performance of the transverse tube and the light pipe were tested by the experimental method, and the experimental correlation between the heat transfer and the resistance of the transverse pipe and the light pipe was fitted out. In order to study the influence of transverse tube structure on the average heat transfer coefficient in the tube, the mechanism of heat transfer enhancement was discussed. The numerical simulation was used to compare the effects of turbulence intensity, thermal boundary layer thickness, Nusselt Nu number of changes. The analysis results show that the reason why the transverse tube heat transfer performance is better than that of the light pipe is that the boundary layer is thin and strong disturbance, and the transverse tube has strong field synergy, mean angle between the total field velocity and temperature gradient minus small.