分离型热管蒸发段流动特性和传热特性的试验研究

A test investigation on the flow and heat transfer characteristics of the evaporation section in a separating type heat pipe.

对分离型热管管内蒸发段流动特性和传热特性进行了试验研究 :在保证热管工作效率及安全性的前提下 ,分离型热管蒸发段工质流动形式除单相液流和泡状流 (低热流密度时为弹状流 )外 ,在蒸发段上部约有 42 %～ 50 %的不稳定飞溅降膜区 ;合理充液率随热流密度的增加而减少 ;随着热流密度的增加 ,核态沸腾区及飞溅降膜区的换热系数均增加 ,蒸发段总换热系数也增加。

A test investigation was made of the flow and heat transfer characteristics of the evaporation section in a separating type heat pipe. Under the condition of guaranteeing the work rate and safety of the heat pipe, there was an unstable, splashing falling film zone of about 42%～50% in the top of the evaporation section besides the single-phase liquid flow and bubble liquid flow in the evaporating section of the separating type heat pipe (or elastic flow in the low heat flow density). The reasonable filling-liquid rate was reduced with the increase of the density of the heat flow; and with the increase of the density of the heat flow, the heat transfer coefficients in the nucleated boiling zone and the splashing falling film zone were increased, the total heat transfer coefficients in the evaporation was also increased.