The Impact of Using Phase Change Materials for Enhancing Thermal Performance of Residential Building Walls in The Extreme Conditions of Mediterranean Region

Abstract

Increasing of energy consumption in residential buildings recently has received a significant concern on the thermal performance of buildings. Reducing energy consumption resulting from the heating and cooling demands of a building and limiting heat loss or gain can play a main role in buildings' saving energy. The thermal insulation of building walls has a significant impact on energy conservation. In this study, a group of models was developed to achieve the best thermal performance for the external walls of residential buildings. Composite wall models enhanced with selected insulation materials have been thermally examined in the extreme conditions in the Mediterranean region to determine the impact of the used materials on the thermal performance of buildings envelopes and energy consumption, with validating results through FLUENT software. The study’s methodology is based on two main stages, analyzing the wall models, and evaluating the most effective thermal performance and the developed ones using FLUENT software based on the location of the insulation layer, thickness, and thermal behavior. The second is investigating heating and cooling loads during winter and summer via DesignBuilder software. The study showed that using Phase Change Material (PCM) insulation materials in the building wall composition has a significant impact on the thermal performance of the building envelope, thermal heat transfer, temperature distribution, and on heating and cooling loads. The heat transfer calculations appeared that the average temperature of the internal surface of the wall can be reduced significantly by almost (1.5-3.5) °C in the summer and by almost (2-6.5) °C in winter when applying Paraffin in an appropriate thickness and location within extreme conditions compared to the system without an insulation layer. The energy calculations of heating and cooling loads obtained showed a reduction in energy demand when using PCM. The saving of heating energy in January was 35.5%, whereas the saving of cooling energy in August was 41.9%. Moreover, the reduction amount of annual energy load was 3013.57kWh with a saving of 40.1% and the payback period was 2.5 years.