Experiments have been performed to investigate the effect of air-flow rate in clearance between the insulation and the wall on the temperature distribution, moisture accumulation, and heat flux. Glass-wool, whose thickness is 100mm and whose density is 16kg/m³, is adopted as a testing material, and the heating surface of the glass-wool and cooled-wall temperature are 25 and -15°C, respectively.
The clearance between surface of glass-wool and cooling walls is 20mm, and inlet air velocity ranges from 0.2 to 1.0m/s. A s a result of the present investigation, it is observed that an increase in both air velocity and cooled-wall temperature causes the decrease in moisture accumulation and heat flux within the glass-wool and that inlet air temperature become very important for evaluating performance of insulation.