Simulation study of heat energy potential of asphalt solar collectors

Abstract

Using black asphalt pavements as solar collectors is an emerging technology for snow-melting of pavements in winter or cooling and heating of adjacent buildings. The primarily concerned issues of this technology are the heat energy potential and its critical parameters. In this paper, a transient, two-dimensional finite element model is developed to investigate the heat transfer process in both neat and conductive asphalt pavements. The results from thermal properties tests show that thermal conductivity of asphalt mixtures may increase by more than 30% due to the addition of conductive fillers. Besides, the modelling results indicate that the higher thermal conductivity may result in acceleration of the heat conduction and increase in temperature at deeper depths in asphalt pavements. According to the calculated results of heat energy potential based upon the model, the energy derived from a neat asphalt collector or a conductive one is considerable. Thermal properties of asphalt materials have no significant impact on energy absorption in asphalt pavements.

The State of the Art: Application of Green Technology in Sustainable Pavement

“…e rst pavement solar collector with embedded pipe systems was implemented by Sedgwick and Patrick with a grid of plastic pipes 20 mm underneath the asphalt surface in a tennis court, demonstrating a relatively constant temperature [60]. Wu et al proposed the use of black asphalt pavements as solar collectors for direct cooling and heating in snow removal in the winter [61]. Major problems are to maintain temperature in the pipe system and to eliminate pipe clogging over time.…”

“…As shown in Figure 7, geothermal energy is collected with pipe networks to generate electricity in many countries, such as Mexico [76] and Turkey [77]; geothermal energy is also applicable to heat pavements for deicing [78]. In the pipe networks, fluid operation parameters, such as temperature and flow rate, have a great influence on the thermal exchange [61].…”

“…Wang et al proposed a small-scale geothermal system to melt ice on concrete pavements, and experimental results showed that the melting process of ice and snow consists of a staring period, a linear period, and an accelerated period [78]. Zhou et al verified the applicability for storing thermal energy and deicing in winter [61]. Liu et al analyzed the heat transfer and snow melting of asphalt concrete pavement and paved the pavement with electric heating pipes [79,80].…”