Experimental Analysis on Factors Influencing External Surface Evaporative Heat Transfer of Aerated Concret
LI Ning and MENG Qing-lin
DOI:10.11835/j.issn.1674-4764.2011.04.022
Received January 09, 2011,Revised , Accepted , Available online July 01, 2015
Volume ,2011,Pages 140-145
- Abstract
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 100mm 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.