Oriented heat induction of phase change asphalt pavement for improving heat transfer efficiency

The low thermal conductivity of phase change material limits its heat storage and cooling effect in asphalt pavement. Considering the multi -layer structure of asphalt pavement, conducting orientated heat induction in the asphalt layer outside the phase change asphalt layer is a novel approach to improve the temperature regulation ability of phase change asphalt pavement. As a result, this paper designed a heat storage and heat induction structure (HS -HIS) by combining the heat -storage top layer and the heat -induction middle and bottom layer. A finite element model was established to study the thermal behavior of HS -HIS and an indoor irradiation test was designed to verify the simulation results. The simulation results show that compared with control structure (CS), the heat storage in the top layer of HS -HIS increased by 14.9 %, while the heat accumulation in the middle layer decreased by 8.7 %, resulting in a decrease in heat flow and temperature inside the pavement. The peak temperature on the surface and at 4 cm depth was 0.5 degree celsius (11: 00 a.m.) and 2.6 degree celsius (13: 00 p.m.) lower than those of CS. Meanwhile, there was a good correlation between the indoor irradiation results and the simulation results. The above results indicate that HS -HIS can be used to effectively enhance heat directional transfer and improve the cooling effect of phase change asphalt pavement.