Heat protection by different phase change materials

Different types of phase change materials (PCMs) were compared for the use in heat protective clothing. For that purpose, flexible blister foils containing the PCMs were prepared. The samples were irradiated with a heat flux of 1.5 kW/m(2) in order to simulate a typical industrial setting like working in front of a hot oven. The temperature evolution behind the foils indicated the performance of each PCM, which was dependent on the duration of the exposure. For irradiation times up to 9 min, sodium acetate trihydrate lead to the lowest temperature increase and thus the best protection. When irradiating more than 9 min, a zeolite type was found to be more suitable, which lead to a lower temperature increase of up to 36 degrees C compared to a reference with no PCM. We developed a simple heat transfer model, taking account of the latent heat of the PCM, of the heat capacity of the foil and of the radiant and natural convective heat flow, which could be applied to predict the effect of PCM containing foils and will be used for further optimizations. (C) 2013 Elsevier Ltd. All rights reserved.