霜形成对翅片管换热器空气侧表面传热系数影响的实验研究

在空冷系统中,换热器空气侧的表面结霜问题是影响其应用和发展的主要问题。通过对结霜条件下翅片管换热器空气侧换热性能的实验研究,得出了空气湿度、翅片间距、风速等参数变化对空气侧当量表面传热系数的影响;结果表明在一定的范围内,结霜前期h0值随结霜时间τ急剧下降,在结霜后期,这些参数对h0值的影响大为削弱。

An experimental investigation on the effect of the frosting on surface heat transfer coefficient of finned heat exchanger

In an air-cooled system,the frosting of heat exchanger at air side is a main problem to limit its application and development.Heat transfer performance of finned-tube heat exchanger at air side was investigated experimentally at the condition of frosting.The effect of the variation of air humidity,fin space and wind speed on equivalent surface heat transfer at air side was obtained.The results showed that at the initial stage of frosting,h0 decreases sharply with increasing frosting time τ;at the later stage of frosting,these parameters have little effect on h0.