A thermal model for phase change materials in a building roof for a tropical and humid climate: Model description and elements of validation

• Published in: Energy and buildings 2014-02, Vol.70, p.71-80
• Main Authors: Guichard, Stéphane, Miranville, Frédéric, Bigot, Dimitri, Boyer, Harry
• Format: Article
• Language: English
• Subjects: Applied sciences; Buildings; Buildings. Public works; Ceilings; Climate; Engineering Sciences; Exact sciences and technology; External envelopes; Materials; Mathematical analysis; Mathematical models; Mechanics; Miscellaneous (including polymer concrete, repair and maintenance products, etc.); Outdoor; Phase change materials; Physics; Roof; Roofs; Sensitivity analysis; Strength of materials (elasticity, plasticity, buckling, etc.); Structural analysis. Stresses; Thermal modeling; Thermics; Validation methodology
• ISSN: 0378-7788
• DOI: 10.1016/j.enbuild.2013.11.079

•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. This article deals with a numerical model of the thermal behavior of a building roof equipped with phase change materials (PCM). The study puts in evidence the first results of the proposed model based on the apparent heat capacity method. A backward Euler scheme and a finite difference discretization method have been used. The model was integrated in a multizone building simulation code and is able to predict both the whole temperature of each building component and the thermal impact of PCMs installed in buildings for several configurations. A first experimental study has been conducted for a tropical and humid climate, using a full-scale outdoor test cell equipped with PCMs installed as a component of the ceiling. It allowed to give elements of validation for the numerical model, through a validation process including comparisons with measurements A sensitivity analysis has also been run to highlight the influencing parameters of the thermal model. The first results from comparisons between model predictions and measurements are encouraging and show a convenient agreement for the given configuration under field conditions.