扰流子折流杆换热器的开发研究(Ⅱ)——低粘度流体中试研究

Development of the Turbulator-Rod Baffle Heat Exchanger (Ⅱ) ——The Invenstigation of the Medium-Sized Device Experiment Using Low Viscosity Fluid

在低粘度流体下对扰流子折流杆换热器和折流杆换热器进行了传热性能和阻力性能的对比实验研究。实验以水作为传热介质，热水走壳程，冷水走管程。实验时壳程流体流动状态基本恒定，而管程流体发生变化。通过实验数据的分析关联，得到了加入扰流子后管程对流传热系数的近似计算模型。结果表明，当雷诺数的范围为１０４ ～５ ×１０４ 时，管程对流传热系数增加的幅度高于阻力增加的幅度，管程对流传热系数和换热器总传热系数分别提高５０ ％ 和１０ ％ 以上。说明对水这样的低粘度流体，在传热湍流区（ 即雷诺数大于１０４ 的范围） ，可以采用较大节距的扰流子来强化传热，以取得较佳的综合效果。

The comparative experimental invenstigation has been finished for the turbulator-rod baffle heat exchanger using the low viscosity fluid. A mathematical model of convective heat transfer coefficients in tube has been obtained by analyzing and relating of the experimental data. Results show that when 10 4< Re <5×10 4, the increasing extent of the convective heat transfer coefficient in tube is higher than that of resistance. The increasing extent of the convective heat transfer coefficient and the heat transfer coeffient is higher than 50% and 10%. This shows that for low viscosity fluid such as water, the longer section distance turbulator can be used to enhance heat transfer in the turbulence zone ( Re >10 4).