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Experimental study the albedo of urban canyon prototype with reflective pavements (streets)

Yinghong Qin 1, Jia Liang 1, Kanghao Tan 1, Fanghua Li 2

Abstract


Urban structures consist of buildings, roofs, walls and streets. Buildings at both sides of the street create a canyon-like environment that is called urban canyon (UC). In a UC, conventional impervious pavements absorb and store solar radiation but negate the evaporative cooling, contributing to the development of urban heat island (UHI). One popular option to mitigate UHI is to make the pavements more reflective than conventional pavements and to absorb less solar radiation in the urban area. However, it remains unknown if a reflective pavement in an urban canyon can effectively reduce the solar absorption of the urban surfaces. This study prepares ten UC prototypes with differential pavement reflectivity and with south-north orientation, west-east orientation, and cross-street orientation, respectively. The albedo of these UC prototypes is measured by a new method that is proposed to estimate the reflectivity of urban canyon prototypes. It is found that raising the albedo of the pavement is inefficient to increase the albedo of the UC, especially for UC with great aspect ratio. In low aspect-ratio UC or parking lot, reflective pavements reflect a sizable additional diffuse radiation to pedestrians. Therefore, it should be caution to develop reflective pavements as urban cooling strategy.

Keywords


Multiple reflections; urban heat island; albedo; reflectivity; diffuse radiation

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References


Panão MNO, Gonçalves HP, Ferrão PC. A matrix approach coupled with monte carlo techniques for solving the net radiative balance of the urban block. Boundary-Layer Meteorology 2007; 122(1): 217-241.

Qin Y, Hiller JE. Understanding pavement-surface energy balance and its implications on cool pavement development. Energy and Buildings 2014; 85(0): 389-399.

Mills GM. Simulation of the energy budget of an urban canyon—I. Model structure and sensitivity test, Atmospheric Environment. Part B. Urban Atmosphere 1993; 27(2): 157-170.

Kastendeuch PP, Najjar G. Simulation and validation of radiative transfers in urbanised areas. Solar Energy 2009; 83(3): 333-341.

Aida M, Gotoh K. Urban albedo as a function of the urban structure — A two-dimensional numerical simulation. Boundary-Layer Meteorology 1982; 23(4): 415-424.

Aida M. Urban albedo as a function of the urban structure — A model experiment. Boundary-Layer Meteorology 1982; 23(4): 405-413.

Fortuniak K. Numerical estimation of the effective albedo of an urban canyon. Theoretical and Applied Climatology 2008; 91(1-4): 245-258.

Qin Y. Urban canyon albedo and its implication on the use of reflective cool pavements. Energy and Buildings 2015; 96(0): 86-94.

Dimoudi A, Zoras S, Kantzioura A, Stogiannou X, Kosmopoulos P, Pallas C. Use of cool materials and other bioclimatic interventions in outdoor places in order to mitigate the urban heat island in a medium size city in Greece. Sustainable Cities and Society 2014; 13: 89-96.

Li H, Harvey JT, Holland TJ, Kayhanian M. The use of reflective and permeable pavements as a potential practice for heat island mitigation and stormwater management. Environmental Research Letters 2013; 8(1): 015023.

Anandakumar K, A study on the partition of net radiation into heat fluxes on a dry asphalt surface. Atmospheric Environment 1999; 33(24–25): 3911-3918.

Akbari H, Rose L. Characterizing the fabric of urban environment: a case study of metropolitan Chicago, Ilinois, in: Paper LBNL-49275, Lawrence Berkeley National Laboratory, Berkeley, CA, 2001.

Akbari H, Konopacki S, Pomerantz M. Cooling energy savings potential of reflective roofs for residential and commercial buildings in the United States. Energy 1999; 24(5): 391-407.

Wang H, Wu S, Chen M, Zhang Y. Numerical simulation on the thermal response of heat-conducting asphalt pavements, Physica Scripta 2010 (T139) (2010) 014041.

Pomerantz M, Akbari H. Cooler paving materials for heat-island mitigation, in: Proceedings of the 1998 ACEEE summers study on energy efficiency in building, 1998, p.135.

Pomerantz M, Akbari H, Chen A, Taha H, Rosenfeld AH. Paving materials for heat island mitigation, in: Lawrence Berkeley National Laboratory Report LBL-38074, Berkeley, CA, 1997.

Karlessi T, Santamouris M. Improving the performance of thermochromic coatings with the use of UV and optical filters tested under accelerated aging conditions. International Journal of Low-Carbon Technologies 2013; 10(1): 45-61.

Synnefa A, Dandou A, Santamouris M, Tombrou M, Soulakellis N, On the use of cool materials as a heat island mitigation strategy. Journal of Applied Meteorology & Climatology 2008; 47(11): 2846-2856.

Synnefa A, Santamouris M, Apostolakis K. On the development, optical properties and thermal performance of cool colored coatings for the urban environment. Solar Energy 2007; 81(4): 488-497.

Ma Y, Zhu B. Research on the preparation of reversibly thermochromic cement based materials at normal temperature. Cement and Concrete Research 2009; 39(2): 90-94.

Karlessi T, Santamouris M, Apostolakis K, Synnefa A, Livada I. Development and testing of thermochromic coatings for buildings and urban structures. Solar Energy 2009; 83(4): 538-551.

Levinson R, Akbari H. Effects of composition and exposure on the solar reflectance of portland cement concrete. Cement and Concrete Research 2002; 32(11): 1679-1698.

Boriboonsomsin K, Reza F. Mix design and benefit evaluation of high solar reflectance concrete for pavements. Transportation Research Record: Journal of the Transportation Research Board 2011 (-1) (2007) 11-20.

Marceau NL, Vangeem MG. Solar reflectance values for concrete: intrinsic materical properties can minimize the heat island effect. Concrete International. 2008; 52-58.

Sultana S. Extending asphalt pavement life with thin whitetopping. Kansas State University 2010.

Pomerantz M, Pon B, Akbari H, Chang SC. The effect of pavements’ temperatures on air temperatures in large cities, in: LBNL 43442, LBNL, Berkeley, CA, 2000; p.1-16.

Santamouris M, Gaitani N, Spanou A, Saliari M, Giannopoulou K, Vasilakopoulou K, Kardomateas T. Using cool paving materials to improve microclimate of urban areas – Design realization and results of the flisvos project. Building and Environment 2012; 53(0): 128-136.

Kinouchi T, Yoshinaka T, Fukae N, Kanda M. Development of cool pavement with dark colared high albedo coating, in: 5th conference for the urban evironment, Vancouver, Canada, 2004, pp. 1-4.

Anak Guntor N, Md Din M, Ponraj M, Iwao K. Thermal performance of developed coating material as cool pavement material for tropical regions. Journal of Materials in Civil Engineering 2014; 26(4): 755-760.

Synnefa A, Dandou A, Santamouris M, Tombrou M, On the use of cool materials as heat island

mitigation strategy, Journal of Applied Meteorology and Climatology 2008; 47: 2846-2857.

Akbari H, Levinson R, Stern S. Procedure for measuring the solar reflectance of flat or curved roofing assemblies. Solar Energy 2008; 82(7): 648-655.

Lynn BH, Carlson TN, Rosenzweig C, Goldberg R, Druyan L, Cox J, Gaffin S, Parshall L, Civerolo K. A modification to the NOAH LSM to simulate heat mitigation strategies in the New York City metropolitan area. Journal of Applied Meteorology and Climatology 2009; 48(2): 199-216.

Levinson R. Near-ground cooling efficacies of trees and high-albedo surfaces. University of California 1997.

Li H. Evaluation of cool pavement strategies for heat island mitigation. Department of civil and environmental engineering, University of California, Davis, 2012.




DOI: http://dx.doi.org/10.18686/ag.v0i0.1134

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