Optimal positioning of phase change material and insulation through numerical investigations to reduce cooling loads in office buildings

Thermal comfort is inevitable in maintaining the healthy mood of the building occupants and hence increases their productivity. The main objective of this work is to identify the optimal positioning of Phase Change Material (PCM)/insulation techniques with respect to the building envelopes to enhance the thermal performance, thereby recommending effective techniques to reduce the cooling load demand of an office building located under different climates in India. Building models by integrating PCM and insulation layers at various locations of the building envelopes were developed using DesignBuilder software and investigated for summer conditions. The results were compared with that of the basic building. It is concluded that the buildings integrated with PCM or insulation at the outer walls exhibited comfortable indoor temperatures than those integrated at the innermost walls, irrespective of the building location. The selection of PCM and insulation for any location is to be made depending upon the average external temperatures of that specific location for effective and enhanced performance. Based upon the average external temperatures, appropriate techniques were recommended for buildings in different climates. Compared to basic building, the recommended buildings yielded a cooling load reduction of 64%, 61%, 57%, 63%, and 58/59% for Bangalore, Delhi, Jodhpur, Pune, and Guwahati.