Abstract
Phase change materials (PCMs) offer significant potential for reducing cooling energy demand and improving thermal comfort in hot climates by increasing the thermal inertia of building envelopes. This study presents a comprehensive evaluation of PCM-enhanced building envelope systems through experimental testing and numerical simulation under extreme hot climate conditions. A prototype wallboard incorporating a bio-based PCM with a melting point of 28°C was fabricated and tested in a controlled environmental chamber replicating summer conditions in a hot arid region. Thermal performance metrics—including peak temperature reduction, time lag, decrement factor, and energy savings—were measured and compared against a conventional wall assembly. Additionally, a validated computational fluid dynamics (CFD) model was employed to parametrically assess the influence of PCM layer thickness, placement, and phase change temperature on overall performance. Results indicate that the PCM-enhanced envelope reduced peak indoor surface temperatures by up to 4.5°C, increased time lag by 2.3 hours, and decreased the decrement factor by 0.18. Annual cooling energy simulations showed a 12–18% reduction in cooling load depending on PCM configuration. The optimal PCM melting temperature was found to be 2–3°C above the average indoor setpoint. These findings demonstrate that strategic PCM integration can substantially enhance building envelope thermal performance in hot climates, contributing to both energy efficiency and occupant comfort.
Keywords
phase change materials, building envelope, thermal performance, hot climate, energy efficiency, thermal comfort, PCM integration, cooling load reduction