EXPERIMENTAL AND COMPUTATIONAL STUDY ON THERMAL PERFORMANCE OF WOOD-PLASTIC COMPOSITES IN BUILDING ENVELOPE

Abstract

Wood-plastic composites (WPCs) are attractive material for enhancing thermal performance of buildings by acting as an insulation surface. A fast and reliable experimental method was devised using a simple quasi-steady heating film (QSHF) method to measure the thermal conductivity of locally manufactured WPCs in Kuwait. QSHF used two blocks of standard materials compared with the classic methods, although it does not require a fixed constant heating source nor a cooling source. QSHF had a 10 cm × 10 cm × 0.5 mm silicon heating film controlled by a temperature controller and several transparent acrylic square blocks of the same size with 10 mm thickness as the standard materials. The top surface of the WPC samples was the cold side of the system, which is open to indoor temperatures of 22-23°C. The bottom layer can be maintained at any desirable temperature ranges from 25° to 55°C using the heating film to simulate the real outdoor environment. The thermal conductivities of locally manufactured WPCs type, namely FB16, FB18W, CD, and TD, were 0.0912, 0.1174, 0.3453, and 0.3078 W/m.K, respectively, obtained within 1 to 3 hours, which all fall below the standard value of 0.414 W/(m².K) for composite walls and 0.1-0.2 W/m.K for wood. Multiphysics CFD simulation for DP45 sample and TRNSYS simulation for FB18W WPC in the building envelop were conducted which showed strong 2D effects and 3.3&#37: reduction in maximum cooling load in Kuwait, respectively.