Experimental evaluation of optical absorption coefficient of insulated vehicle sandwich panel at the sun radiation

The energy consumption of refrigerated vehicles depends on dispersions of the insulated boxes; during loading and unloading of goods there is an additional thermal load due to the doors opening and the incident solar radiation. The main purpose of this study is to show the experimental setting in order to determine the radiative absorption coefficient of the sandwich panel constituted by GFRP (Glass Fibre Reinforced Plastic), polyurethane and GFRP, by the use of IR thermocamera. The result is fundamental to evaluate the thermal load of an insulated vehicle, when it is stopped and the sun is shining. This phenomenon is now neglected by the international standards (ATP, above all). On the other side, the sun thermal load is fundamental in the evaluation of the power consumption of a refrigerated vehicle. Also the future projects of energy labelling of refrigerated vehicles must take into account the sun radiation contribution (van Gerwen et al.,1999).