Article

Harvesting heat energy from asphalt pavements: development of and comparison between numerical models and experiment

International Journal of Sustainable Engineering 06/2012; 5(2):159-169. DOI: 10.1080/19397038.2011.574742

ABSTRACT

The use of flowing water in embedded pipes to harvest heat energy from asphalt pavements and thereby reducing its temperature and the urban heat island effect has been proposed. A successful use of such an approach would require a complete understanding of the effect and the interaction of various mechanisms such as conduction, convection and radiation and factors such as solar radiation, diameter of pipe and rate of flow. A large-scale experiment was conducted to understand such effects, and numerical modelling was conducted for prediction of temperature. The experiment was modelled using finite element method, and a good match was obtained between predicted and experimentally obtained results. Effects of pipe diameter and flow rate were also analysed. This model could be used in future for selection of appropriate levels of critical variables and hence successful implementation of this concept to sustainable pavements.

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Available from: Rajib B. Mallick, Oct 30, 2015
    • "As a consequence, and according to existing literature, an asphalt concrete PSC can harvest more thermal energy compared to cementitious concrete PSC's [3]. It was shown that a PSC can reduce the maximum pavement temperature by about 5 °C, which also leads to a reduction in surface temperature and thus emission of longwave radiation and convective heat transfer [8] [9]. A reduction of the maximum pavement temperature will reduce the potential rutting damage and fatigue due to oxidation of the binder in the case of asphalt concrete roads. "
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