管壳式换热器壳侧传热与阻力性能的实验研究与预测

设计并建立了换热器传热与阻力的综合性能实验台,对1种弓形折流板换热器和2种连续螺旋折流板换热器壳侧的传热及阻力性能进行了实验研究,实验介质管侧为水,壳侧为油;同时基于壳侧传热实验数据;应用遗传算法预测了换热器的总换热量。实验结果表明:在相同的壳侧流量下,螺旋折流板换热器的阻力要高于弓型折流板换热器,正进正出螺旋折流板换热器的阻力高于侧进侧出螺旋折流板换热器;螺旋折流板换热器的换热系数高于弓型折流板换热器,侧进侧出螺旋折流板换热器高于正进正出螺旋折流板换热器,而且流量越大这种优势越明显。预测结果表明通过遗传算法得到的传热关联式所得的换热量比采用线性回归所得的更加接近实验数据,表明遗传算法可应用于工程中换热设备性能的预测。

Experimental Study and Prediction of Pressure Drop and Heat Transfer in Shell-side of Tube-and-shell Heat Exchangers

Performances of heat transfer and pressure drop through shell-side in three types of shell-and-tube heat exchangers, of which one with conventional segmental baffles and the other two with continuous helical baffles, were experimentally carried out with water flowing in tube-side and oil flowing in shell-side. Genetic algorithm was used to predict heat transfer performances based on searching constants of correlations under limited experimental data. The experimental results show that under the same flow rate in shell-side, the heat exchangers with continuous helical baffles offer higher total pressure drop and heat transfer coefficient than that of heat exchanger with segmental baffles, especially increase with the increase of fluid flow rate. The predicted heat transfer rates based on correlations, of which their constants determined by means of genetic algorithms, enable the closer fit to experimental data than those by regression analysis in the reference, indicating that genetic algorithm may be recommended to predict performance of heat exchange devices in engineering application.