Utilizing solar energy for anti-icing road surfaces using hydronic heating pavement with low temperature
Doctoral thesis, 2019

During summer, the surface temperature of an asphalt road pavement can rise up to 70°C due to absorbed solar radiation. The high temperature degrades the performance of the asphalt concrete by accelerating the thermal oxidation and plastic deformation, especially under heavy traffic loads. On the contrary, during winter, the temperature of road surfaces can reduce below the temperature of the ambient air due to the radiative heat loss. The low temperature hardens the asphalt pavement and makes it more susceptible to thermal cracking. Moreover, the low temperature causes the road surface to get slippery and hereby increases the risk for traffic accidents. A potentially environmental-friendly method to overcome the abovementioned problems is to use a Hydronic Heating Pavement (HHP). The HHP system consists of embedded pipes in the road. A fluid as thermal energy carrier circulates through the pipes. During sunny days, when the road surface is warm, the energy is harvested and saved in seasonal thermal energy storages. During cold days, the warm fluid from the storage is pumped back to the pipes to increase the surface temperature.

The aim of this study is to investigate the feasibility of the HHP system for harvesting solar energy during summer and anti-icing the road surface during winter. The study is done in five different steps: (i) determining the thermal properties of three typical asphalt concrete used for the construction of roads in Sweden using experimental tests and numerical simulation models, (ii) developing a 2D numerical simulation model of the HHP system to find out the most suitable boundary condition equations associated with the heat transfer interactions between the road surface and surrounding climate as well as the initial results related to the required energy for anti-icing the road surface and remaining number of hours of the slippery condition on the road surface, (iii) developing a hybrid 3D numerical simulation model of the HHP system to obtain the fluid temperature decline along the pipes and the effects of the fluid flow rate on the performance of the HHP system, (iv) calculating the minimum required energy for anti-icing the road surface using optimization tools so no slippery condition remains on the road surface and (v) investigating the feasibility of the coupled HHP system to a Horizontal Ground Heat Exchanger (HGHE) for harvesting solar energy and anti-icing the road surface. The numerical simulation model of the HHP system is made based on the finite element method and validated by the experimental results and analytical solutions as well as by the results of the other numerical simulation models from literature.

The results associated with the thermal properties show that the thermal conductivity of asphalt concrete can vary from 1 W/(m·K) to 3 W/(m·K). The results associated with the 2D numerical simulation model shows that the annual required energy for anti-icing is about 75  and the remaining number of hours of the slippery condition after heating the road surface is 128 hours. The results associated with the hybrid 3D numerical simulation model show that the annual required energy for anti-icing is about 84  and the remaining number of hours of the slippery condition after heating the road surface is 217 hours. The results associated with the optimization show that the minimum annual required energy for anti-icing the road surface is 107  which results in remaining only 3 hours of the slippery condition on the road surface. Furthermore, the results associated with the coupled HHP system to the HGHE show that the annual required energy for anti-icing is about 75  and the remaining number of hours of the slippery condition is 580 hours.

solar energy

asphalt concrete

ground heat exchanger

anti-icing

optimization

Room SB-H2 on Sven Hultins gata 6, Chalmers.
Opponent: Professor Jeffrey D. Spitler, Oklahoma State University, USA

Author

Raheb Mirzanamadi

Chalmers, Architecture and Civil Engineering, Building Technology

Thermal properties of asphalt concrete: A numerical and experimental study

Construction and Building Materials,; Vol. 158(2018)p. 774-785

Journal article

Anti-icing of road surfaces using Hydronic Heating Pavement with low temperature

Cold Regions Science and Technology,; Vol. 145(2018)p. 106-118

Journal article

Mirzanamadi. R. Hagentoft. C.E., Johansson. P., “Parametric study of hydronic heating pavement for anti-icing road surfaces using a hybrid 3D numerical simulation model”., Conference of IBPSA – Italy 2-4 Sept. 2019, Submitted.

An analysis of hydronic heating pavement to optimize the required energy for anti-icing

Applied Thermal Engineering,; Vol. 144(2018)p. 278-290

Journal article

Mirzanamadi. R. Hagentoft. C.E., Johansson. P., “Coupling a hydronic heating pavement to a horizontal ground heat exchanger for harvesting solar energy and heating road surfaces”., Submitted to a scientific journal.

The project of “safe and ice-free roads using renewable energy”, aims at examining the possibility of utilizing harvested solar energy during summer for anti-icing the road surface during winter. In this thesis, five different steps were taken for studying this possibility. The first step was to determine the accurate thermal properties of three typical asphalt concretes used for the construction of roads in Sweden. The second step was to develop a 2D numerical simulation model of a Hydronic Heating Pavement (HHP). The 2D model was able to calculate the required energy for anti-icing the road surface and to obtain the remaining number of hours of the slippery condition on the road surface. The 2D model was a dynamic numerical simulation model, which was able to turn on/off the heating system based on the slippery condition on the road surface. However, the 2D model was not able to calculate the fluid temperature decline along the pipes and also was not able to investigate the effects of the fluid flow rate on the efficiency of the HHP system. In order to solve this problem, a hybrid 3D numerical simulation model was developed. The hybrid 3D numerical simulation model was developed by serially connecting 2D numerical simulation model. The 2D models were connected to each other through the convective heat transfer along the pipe. Moreover, the hybrid 3D numerical simulation model was used: (i) to obtain the minimum required energy for totally preventing ice formation on the road surface and (ii) to investigate the feasibility of the coupled HHP system to a horizontal ground heat exchanger.

Driving Forces

Sustainable development

Areas of Advance

Transport

Energy

Subject Categories

Energy Engineering

Infrastructure Engineering

Building Technologies

ISBN

978-91-7597-854-3

Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 4535

Publisher

Chalmers University of Technology

Room SB-H2 on Sven Hultins gata 6, Chalmers.

Opponent: Professor Jeffrey D. Spitler, Oklahoma State University, USA

More information

Latest update

1/11/2019