Thermal behaviour of a wall-lining containing phase change materials

In temperate climates like UK, buildings constructed with high thermal mass materials have the intrinsic capacity to alleviate the effect of overheating in the summer. Phase change materials (PCMs), which have a high latent heat capacity to volume ratio is a potential effective means to improve the thermal capacity of light-weight or existing buildings. The feasibility of applying PCMs in buildings was investigated through a research and development collaboration between University of Brighton and OMNOVA Wallcoverings (UK) Ltd. The aim was to develop a PCM wall-lining which can reduce energy consumption of buildings, by minimising the use of air-conditioning, and improve the thermal comfort during periods of extreme climate conditions. This paper reports on the measured experimental findings of the thermal performance of a prototype phase change wall-lining developed and manufactured. Samples of the prototypes were tested using Differential Scanning Calorimeter (DSC) in the laboratory which provided evidence of the projected and actual sensible-latent heat transfer behaviour of the micro-encapsulated PCM. In order to evaluate the thermal performance in actual installed conditions, the prototype wall-linings were subject to a regime of cyclic environmental conditions in a 13.8m3 chamber. The results were compared with a control chamber that was subject to the same conditions but without the phase change wall-lining. The experiments provided measured data on the effect of different supply air conditions to the charging and discharging behaviour of the wall-lining, the amount of energy stored and the moderation of peak temperatures. These experimental results enabled the evaluation of the effectiveness of the latent heat storage by the PCMs within the wall-lining and are analysed and discussed.