新型规整填料换热器传热的理论与实验研究

Theoretical and experimental study on heat transfer performance of novel structured packing heat exchanger

提出了一种用于制冷供暖的新型规整填料室外换热器。基于Poppe传热传质数学模型,构建了新型换热器的三维数学模型,并对其进行了实验验证。用水作为热泵系统模拟工质,考察了该换热器在干填料状态下的传热性能,并通过喷淋水辅助的方法提升换热器的换热效果。在华北夏季的真实工况下,考察了包括工作介质温度、空气流量、喷淋水量、空气温度及湿度等一系列因素对实验系统传热性能的影响。实验确定了该新型换热器能在较宽的工质温度范围内保持较稳定的总传热系数,传热速率随喷淋水量及空气流量的增大而增大。综合考虑确定了0.588 L/(m2·s)的最优喷淋密度。不同空气条件下的传热实验结果表明,较低的空气湿度更有利于夏季喷淋水辅助的传热过程。

A novel structured packing heat-exchanging device for space cooling was presented. A three dimensional heat transfer model was proposed based on the Poppe method to simulate the heat transfer process of this equipment,and the experiments were conducted to validate the model. Using water as working medium in the heat pump system,heat transfer performance of this heat exchanger under dry condition was tested and heat transfer efficiency was greatly improved with the assistance of sparkling water. In the summer of north China,a series of experiments were conducted to investigate the effects of the factors including working medium temperature,air and sparkling water flowrates,air temperature and humidity on the heat transfer performance of this experimental system. The results reveal that the overall heat transfer coefficient of the heat exchanger can be nearly constant in a wide range of the working medium temperatures. Heat transfer rate increases constantly with the increases of air and sparkling water flowrates and a balanced sparkling density of 0. 588 L/（ m2· s） was determined for this heat exchanger. The testing results under different air conditions indicate that a relatively lower humidity is good for the heat transfer processes with the assistance of sparkling water.