Thermal properties of phase change thermal storage foam concrete

In order to seek building materials with energy-saving effect, a phase change thermal storage foam concrete with thermal storage and temperature regulation capabilities was prepared by means of experimental design and numerical simulation. Its dry density grade is 700 kg/m3, the content of shaped composite phase change material accounted for 0%, 3%, 6%, 9%, 12% and 15% of the mass of the cementitious material, respectively. The influence of shaped composite phase change materials on the dry density, compressive strength and thermal properties of foam concrete was explored, and the finite element software ABAQUS was used to establish the wall model of phase change thermal storage foam concrete, and the heat storage and temperature regulating performance of phase change thermal storage foam concrete wall was studied. The experiment results show that the dry density, compressive strength and thermal conductivity of the phase change thermal storage foam concrete gradually decrease with the increase of the content of the shaped composite phase change material. When the content of the shaped composite phase change material is 15%, the dry density, compressive strength and thermal conductivity reach the minimum values, which are 661 kg/m3, 2.18 MPa and 0.144 W/(m·K), respectively. With the increase of the content of shaped composite phase change material, the phase change temperature, phase change latent heat and specific heat capacity of foam concrete also increase. When the content of shaped composite phase change material is 15%, the phase change temperature is 24.83℃, the phase change latent heat is 12.320 J/g, and the specific heat capacity is 1 462 J/(kg·℃). The finite element simulation results show that when the content of the shaped composite phase change material is 15%, the temperature fluctuation range of the inner surface of the phase change thermal storage foam concrete wall is 25.37-26.57℃, and the maximum temperature difference is 1.20℃, which is 0.46℃ lower than that of pure foam concrete, the time to the highest temperature is delayed by 1.83 h, and the time to reach the lowest temperature is delayed by 1.16 h compared with the pure foam concrete wall. When the phase change thermal storage foam concrete is arranged inside the wall, its thermal storage and temperature regulation effect are the best. © 2023 Beijing University of Aeronautics and Astronautics (BUAA). All rights reserved.