在热湿气候风洞内,用正交实验研究了一定初始含水率下加气混凝土蒸发换热的影响因素.从对蒸发换热量影响的显著性和持久性来衡量,太阳辐射居首,其次是试件厚度,再者是风速,最后是温度,而相对湿度的影响较小,温度和相对湿度的交互作用亦不显著.太阳辐射、风速、温度及试件厚度对材料蒸发换热量影响最显著的水平分别为400 W/m2、1.5 m/s、30℃、100 mm.其原因是太高的辐射和温度导致了材料表层温度过高,表面蒸发过快而“干化”,从而阻碍材料内部水分向表层的迁移；而过高的风速和过厚的材料也对其自身蒸发换热产生负面影响.%Experiment of aerated concrete evaporation under certain initial water content was carried out in the hot-humid climatic wind tunnel. By orthogonal experiment, the influencing factors of evaporative heat transfer are analyzed. Measured from the significant and persistent of impact, solar radiation is the greatest influencing factor, then followed by the sample thickness, air velocity is in the third order, and the last is ambient air temperature. Air relative humidity and the interaction with air temperature have no statistically significant influence. It is observed that the most dramatically significant level of infrared power, air velocity, air temperature and sample thickness on the evaporative heat transfer are 400 w/m2, 1. 5 m/s, 30℃ and l00mm respectively. This is because the increase in infrared power and air temperature may have caused a rapid increase in the temperature at sample surface, resulting in excess water loss of surface layer to desiccation and thus in retarding the interior moisture migrating up to the surface for further evaporation. And over-high air velocity and over-thick material may also have negative influence on evaporation.
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