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以管程扰流雷诺数、努塞尔数和达尔西阻力因数中的特征长度为切入点,结合各特征数的物理意义提出管程扰流特征长度选取准则。指出管程扰流有动态扰流和静态扰流之分,应选取不同的特征长度。进而结合管程转子组合式强化传热与自清洁装置“洁能芯”的传热和阻力实验,将不同特征长度条件下的实验数据处理结果进行比较讨论,验证管程扰流特征长度选取准则,同时也阐述转子组合式强化传热装置“洁能芯”的强化传热与阻力特性。实验表明,当21 000≤Re≤56 000,与光滑圆管相比,“洁能芯”使得管程努塞尔数提高15%～20%,总传热系数提高约20%,达尔西阻力因数约为光管的3倍～5倍。实验中特征速度和定性温度分别为管程平均流速和平均温度。所提出的管程扰流特征长度选取准则对于内插件管程扰流强化传热技术具有普遍的参考价值。
Based on the characteristic length of pipe-flow Reynolds number, Nusselt number and Dresdner resistance factor, the criterion for selection of pipe-length spoiler feature length is proposed according to the physical meaning of each characteristic number. It is pointed out that there are two kinds of dynamic turbulence disturbances and static turbulence disturbances in the turbulent flow field of pipelines. Different feature lengths should be chosen. Combining with the heat transfer and resistance experiment of combined heat transfer and self-cleaning device of pipe-rotor combined heat-cleaning and self-cleaning device, the experimental data processing results under different characteristic lengths are compared and discussed to verify the characteristic length Selection criteria, but also describes the rotor combined heat transfer enhancement device “Jie Nengxin ” enhanced heat transfer and resistance characteristics. Experiments show that when 21 000≤Re≤56 000, compared with the smooth tube, “JENENG” can increase the Nusselt number by 15% ~ 20% and the total heat transfer coefficient by about 20% Western resistance factor is about 3 times the light tube ~ 5 times. In the experiment, the characteristic velocity and the qualitative temperature are the average flow velocity and the average temperature of the tube. The proposed criterion for choosing the length of the spoiler flow has the universal reference value for the inter-pipe spoiler enhancement heat transfer technology.