微液层模型预测过冷沸腾的临界热流密度

本文利用微液层模型对过冷沸腾的临界热流密度（CHF）进行了理论预测。过冷沸腾的强化换热主要是通过单个气泡的形成和消失造成的对流换热强化而引起的。对等热流面,CHF在高过冷区趋近于常数;对等温面,CHF随过冷度的增加而增加。过冷度增加时,蒸发换热量减少,总热流密度主要由蒸发区外的导热引起。

CRITICAL HEAT FLUX PREDICTION OF SUBCOOLED BOILING BASED ON THE MICROLAYER MODEL

The critical heat flux (CHF) of subcooled boiling is theoretically predicted by using the microlayer model. The enhancement of heat transfer for subcooled boiling is mainly contributed by the augmented heat convection caused by the forming and collapsing of individual bubbles. For uniform heat flux surface, the CHF approaches a constant at high subcooling region. For uniform temperature surface, the CHF increases with the subcooling. The evaporative heat transfer becomes small and the total heat flux is mainly contributed by the heat conduction outside the evaporating area as the subcooling is increased.