A Coupled Modelling Method for the Evaluation of the Impact of Pavement Solar Collector on Urban Air Temperature and Thermal Collection

Abstract

The Urban Heat Island (UHI) effect is a phenomenon whereby urban areas become warmer than their surrounding rural areas, due to the replacement of vegetation and soil with surfaces such as asphalt and concrete. The asphalt pavement surfaces tend to absorb a large amount of heat through solar radiation and increase the air temperature, which affects the operation of building heating and cooling systems, causing environmental problems and thermal discomfort. However, this energy can be collected by water circulated through buried copper pipes to cool down temperatures and be stored for other usages. This work aims to develop a method for determining the optimum areas to locate pavement solar collector (PSC) systems and simulate the reduction of ambient air and surface temperature by using a coupled computational modelling approach. Discrete ordinate model and solar-ray tracing were utilised for solar radiation effect modelling in the 3D simulation. Furthermore, the PSC prototype was developed, and lab-scale experiments were carried out for validation. Based on the simulated conditions, in the unshaded area, the asphalt slab's near-surface temperature was reduced by up to 10℃ and the outlet water temperature increased by about 5℃. At the pedestrian height level, the air temperature was reduced up to 4.6℃. This study further expands the investigation of the variation of outdoor conditions such as air temperature and solar radiation. The results showed that the proposed method could be used to optimise the pavement solar collector's positioning to reduce urban surface and air temperature.

Effect of Thermal Variances on Flexible Pavements

“…The characteristics of pavement materials, traffic, climate, and service results affect each other in the design process and determine the demand for a necessary mix of pavement structures [43]. The researchers [55] put forward a computer method that uses the Temperature Equivalency Facteurs concept [56] and introduces the Temperature Factor as a significant factor in the asphalt pavement construction method, which translates the design effect times of the axle load into a standard reference temperature.…”

“…According to a more precise technique for considering the non-uniform temperature distribution, the asphalt pavement thickness may be split into multiple levels in the depth of the scope. Analysis indicates that the technique of division level and the method of the asphalt pavement's equivalent temperature provide comparable findings [55][56][57].…”

Evidence-based Guidance on Reflective Pavement for Urban Heat Mitigation: A Case Study in Phoenix, Arizona

“…CP often refers to multiple technologies that create a cooler surface than traditional concrete or asphalt concrete. RP is one of these CP technologies accomplished via coatings 23,25 , with further CP technologies including phase-change material pavement 28 , highly conductive pavements 28 , pavement as solar collectors 35,36 , and permeable pavement, i.e., porous pavement 23 and water-retentive pavement 37 .…”