无短路区新型螺旋折流板换热器换热性能的实验研究

为了消除目前在工业过程中大量使用的螺旋折流板换热器壳程的三角区漏流,首次采用折面折流板代替平面折流板,对其进行了结构改进.通过采用折面折流板,封闭了相邻两块平面折流板在搭接处产生的三角形豁口,消除了由于豁口导致的壳程短路流道,从而改进了换热器壳侧的流场.实验结果表明,用折面折流板代替平面折流板后,换热器的总传热系数增加了7.9％～9.7％,有效地提高了换热器的换热性能.虽然换热器壳程的阻力损失有所增加,但泵耗功率的增量小于2W,相对于换热量的增加可以忽略不计.此项研究对于换热器的节能优化设计具有重要的指导意义.

Experiment on Heat Transfer Performance of Helical Baffled Heat Exchanger Without Short Circuit Flow

In order to eliminate the shell-side leakage flow in triangle zones,the configuration of helical baffled heat exchanger widely used in industrial processes was improved by using fold baffles.The triangle leakage zone near the joint point between two plain baffles is blocked by the fold baffles,which eliminates the short circuit flow and improves the flow field.The experimental results show that the overall heat transfer coefficient of the heat exchanger increases by 7.9%-9.7%,which effectively improves the heat transfer performance of the helical baffled heat exchanger.Although the shell-side pressure drop correspondingly increases,the increment of the pump power consumption is less than 2 W,which can be ignored compared with the increment of heat exchange.The results of the investigation are valuable to the energy saving optimum design of helical baffled heat exchangers.