板式换热器换热特性及压降的实验研究

为了研究强化板式换热器的换热性能及压降特性，利用小型R32制冷系统，基于钎焊式板式换热器，进行了一系列实验。实验结果表明：板式换热器出口制冷剂由过热到两相态时，制冷剂侧换热系数先急剧增大后缓慢降低，传热温差快速减小后缓慢降低，压降只有小幅度的变化；随着换热器的效能逐渐增大，平衡换热器效能和系统性能后，蒸发器出口干度接近1时，换热效果最好。研究可为强化板式换热器的设计提供参考。

Experimental Study on Heat Transfer Characteristics and Pressure Drop for Plate Heat Exchanger

In order to study the heat transfer performance and pressure drop characteristics of plate heat exchanger,based on the brazed plate heat exchanger,a series of experiments were carried out by using small R32 refrigeration system. The experimental results show that: the refrigerant outlet state from overheat to the two phase state, the heat transfer coefficient on refrigerant side increases rapidly initially and then decreases slowly, the temperature difference of heat transfer decreases quickly and then decreases slowly, the pressure drop only has a small decline.As the effectiveness of plate heat exchanger increases gradually, balance the effectiveness of plate heat exchanger and system performance, the evaporator outlet dryness is close to one, the heat transfer performance reaches the best. This study can provide reference for the design of plate heat exchanger.