Dynamic Thermal Performance and Economic Optimization of Building Walls with Phase Change Material

Abstract

This study presents a comprehensive analysis of transient heat transfer in sustainable building walls, focusing on optimising the thickness of the phase change material (PCM) to enhance the thermal performance of building walls. The investigation employs advanced numerical simulation techniques to get accurate and efficient analysis. We applied Dirichlet boundary conditions on both sides of the wall for one full year while considering the heat transfer by convection and radiation to represent the realistic boundary with a range of PCM thickness. The research aims to identify the optimal thickness that offers the most efficient thermal regulation within the enclosed space. The study findings are presented in terms of yearly energy load, yearly energy storage, yearly energy cost, yearly cost saving, net life saving, and energy saving percentage. The optimal case combinations were selected based on higher energy-saving percentages and higher net cost-life savings. In brick-based solutions, the optimal combination achieved an energy-saving percentage of 71.861%, corresponding to net cost-life savings of 164.896 USD/m2. Similarly, for concrete-based solutions, the optimal combination resulted in an energy-saving percentage of 87.545%, corresponding to net cost-life savings of 571.066 USD/m2. The results offer valuable insights into designing environmentally sustainable building walls with improved thermal performance, emphasising the strategic integration of the PCM for optimal energy efficiency.

Keywords

• Transient Heat Transfer, Phase Change Materials, Heat Storage, Effective Heat Capacity model, optimisation based on savings