竖直狭缝通道中液氮沸腾强化换热的实验研究

实验表明，狭缝间隙对液氮自然对流核态沸腾换热有明显的影响，在低热流密度下，间隙小的狭缝沸腾换热比间隙大的狭缝明显增强，当狭缝间隙小于实验压力下气泡的脱离直径时，对于同样的热流密度，传热温差减小一个数量级以上，沸腾换热系数提高十几倍到二十倍以上，当热流密度增加一定程度（＞4W/cm^2)时，间隙小的狭缝沸腾换热比间隙大的狭缝有所减弱。

EXPERIMENTAL RESEARCH ON THE ENHANCEMENT OF BOILING HEAT TRANSFER OF LIQUID NITROGEN IN VERTICAL NARROW CHANNEL

The experiment indicated that the gap of narrow channel obviously affected the natural convection nucleate boiling heat transfer For low heat flux,the boiling heat transfer of small channel gap is more obviously enhanced than that of big channel gap When the channel gap is smaller than departure diameter of bubble at experimental pressure,for the same heat flux,the temperature difference decreases in the order of more than 1,but the boiling heat transfer coefficient increases by 10 to 20 times When heat flux increases to a certain degree(>4 W/cm 2),heat transfer in small gap channels becomes weaker than in channels with wide gap