Field evaluation of the effects of air convection in energy harvesting asphalt pavements

Abstract

In this article, the performance of a convection-powered air flow through an asphalt prototype pavement is investigated in a field test. An asphalt prototype pavement with pipes buried in its aggregate layer was connected to a constant temperature heat source and installed at the University of Nottingham, UK. In the experimental configuration chosen, air at 15°C was free to flow through the prototype pavement by natural convection and exit through a vertical chimney. The natural convection flow was meant to cool down or heat up the pavement based on the temperature gradient between the pavement surface and the air in the pipes. The experimental setup included a weather station and aimed to analyse the effect of the heat fluxes from and to the air in the pipes on the development of the surface temperature.The experimental results produced a large dataset, which was analysed based on physical and statistical principles to provide guidance for future studies in the field. The system designed was able to provide pavement heating and cooling effectively in a real life environment. The maximum extent of the heating and cooling effects was quantified as ±5°C.