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The use of phase change materials (PCMs) as a building integrated thermal storage may contribute to improving building energy performances. This article focuses on the integration of PCMs in the roof with a non-ventilated air layer, in order to assess thermal performances of a dedicated test cell, especially for thermal comfort. An experimental equipment was set up at Reunion Island under tropical and humid climatic conditions. A mathematical model, based on the apparent heat capacity method is used to predict the actual impact of PCMs on energy consumption as well as thermal comfort. Once the comparisons are performed with simulations, the use of the psychrometric chart, Predicted Mean Vote and Predicted Percentage of Dissatisfied indexes, shows that in the tested configurations, thermal comfort can be improved. Indeed, as well as to enhance the thermal energy storage, the given configuration also reduce the solar radiation through the roof, due to the reflective properties of PCMs panel surfaces. A positive effect on inside air temperature of the full-scale experimental test cell is particularly observed. [ABSTRACT FROM AUTHOR]

This paper deals with the empirical validation of a building thermal model of a complex roof including a phase change material (PCM). A mathematical model dedicated to PCMs based on the heat apparent capacity method was implemented in a multi-zone building simulation code, the aim being to increase the understanding of the thermal behavior of the whole building with PCM technologies. In order to empirically validate the model, the methodology is based both on numerical and experimental studies. A parametric sensitivity analysis was performed and a set of parameters of the thermal model has been identified for optimization. The use of the generic optimization program called GenOpt® coupled to the building simulation code enabled to determine the set of adequate parameters. We first present the empirical validation methodology and main results of previous work. We then give an overview of GenOpt® and its coupling with the building simulation code. Finally, once the optimization results are obtained, comparisons of the thermal predictions with measurements are found to be acceptable and are presented. [ABSTRACT FROM AUTHOR]

This article deals with a new configuration of a complex roof using a phase change material (PCM) installed on a dedicated test cell. For the first time and in field conditions, an experimental device using phase change material was set up at Reunion Island, location having a tropical and humid climate. Results show that in the tested configurations and for a non-ventilated air layer, the measured temperatures were on either side of the PCM's melting point. It means that the PCM is able to store thermal energy in the daytime and release it at night. Furthermore, this study allowed to determine the thermal resistance of the roof via a mean method meeting international standards (ISO 9869) using dynamic data. The method was implemented in a multi-zone building software, named ISOLAB, in order to automatically determine the thermal indicator. [ABSTRACT FROM AUTHOR]

Highlights: [•] A model phase change materials (PCMs) integrated in a complex roof of building is presented. [•] The first two steps of the validation methodology of numerical model of thermal behavior of phase change materials are highlighted. [•] The model is able to predict thermal behavior of PCM. [•] The thermal impact of PCM on the inside air temperature of building is discussed. [ABSTRACT FROM AUTHOR]