Shading Effect on Outdoor Thermal Comfort in High-Density City a Case Based Study of Beijing

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Abstract:

Shading provided by buildings affects outdoor thermal environments and, therefore, influences the long-term thermal comfort of people in outdoor spaces. This study conducted several field experiments to analyze the outdoor thermal conditions on urban streets in central business district (CBD) of Beijing. The RayMan model was utilized for calculating Sky view factor (SVF) and outdoor thermal comfort using meteorological data of one year period. Analytical results indicate that slightly shaded areas (SVF > 0.5) typically have highly frequent hot conditions during summer, particularly at noon; however, highly shaded locations (SVF < 0.3) generally reduce the intra-urban air temperature in winter; moderately shaded areas (0.3 < SVF < 0.5) show the advantage for balancing the hot conditions in summer and cold conditions in winter throughout whole year. Sky view factor can be used as a comprehensive and practical urban planning index at local scale, i.e. urban canyon street and residential estate. It provides a novelty method on scientific planning and sustainable development of city.

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Periodical:

Advanced Materials Research (Volumes 1065-1069)

Pages:

2927-2930

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Online since:

December 2014

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[1] R. Giridharan, S. Ganesan, B. Givoni. Urban design factors influencing heat island intensity in high-rise high-density environments of Hong Kong. Building and Environment. 42(36): 69-84. (2007).

DOI: 10.1016/j.buildenv.2006.09.011

Google Scholar

[2] I. Eliasson, I. Knez, U. Westerberg, S. Thorsson, F. Lindberg. Climate and behavior in a Nordic city. Landscape and Urban Planning. 82: 72-84. (2007).

DOI: 10.1016/j.landurbplan.2007.01.020

Google Scholar

[3] T.P. Lin, Y.F. Ho, Y.S. Huang. Seasonal effect of pavement on outdoor thermal environments in subtropical Taiwan. Building and Environment. 42(41): 24-31. (2007).

DOI: 10.1016/j.buildenv.2006.11.031

Google Scholar

[4] T.P. Lin, A. Matzarakis. Tourism climate and thermal comfort in Sun Moon Lake, Taiwan. International Journal of Biometeorology. 52: 281- 90. (2008).

DOI: 10.1007/s00484-007-0122-7

Google Scholar

[5] R. Giridharan, S. Ganesan. Nocturnal heat island effect in urban residential developments of Hong Kong. Energy and Buildings. 37(9): 64-71. (2005).

DOI: 10.1016/j.enbuild.2004.12.005

Google Scholar

[6] R. Hamdi, G. Schayes. Sensitivity study of the urban heat island intensity to urban characteristics. International Journal of Climatology. 28: 973-82. (2007).

DOI: 10.1002/joc.1598

Google Scholar

[7] F. Bourbia, F. Boucheriba. Impact of street design on urban microclimate for semi arid climate (Constantine). Renewable Energy. 35(2): 343-347. (2010).

DOI: 10.1016/j.renene.2009.07.017

Google Scholar

[8] P. Höppe. The physiological equivalent temperature-a universal index for the biometeorological assessment of the thermal environment. Int. J. Biometeorol, 43(2): 71-5. (1999).

DOI: 10.1007/s004840050118

Google Scholar

[9] A. Matzarakis, H. Mayer. Heat stress in Greece. Int. J. Biometeorol. 41(1): 34-39. (1997).

Google Scholar

[10] H. Andrade, M-J. Alcoforado. Microclimatic variation of thermal comfort in a district of Lisbon (Telheiras) at night. Theoretical and Applied Climatology. 92(2): 25-37. (2007).

DOI: 10.1007/s00704-007-0321-5

Google Scholar

[11] S. Oliveira, H. Andrade. An initial assessment of the bioclimatic comfort in an outdoor public space in Lisbon. International Journal of Biometeorology. 52: 69-84. (2007).

DOI: 10.1007/s00484-007-0100-0

Google Scholar

[12] R.L. Hwang, T.P. Lin, A. Matzarakis. Seasonal effects of urban street shading on long-term outdoor thermal comfort. Building and Environment. 46(4): 863 -870. (2011).

DOI: 10.1016/j.buildenv.2010.10.017

Google Scholar

[13] A. Gulyas, J. Unger, A. Matzarakis. Assessment of the microclimatic and human comfort conditions in a complex urban environment: modelling and measurements. Building and Environment. 41(17): 13-22. (2006).

DOI: 10.1016/j.buildenv.2005.07.001

Google Scholar

[14] VDI. Methods for the human bio-meteorological evaluation of climate and air quality for the urban and regional planning. Part I: climate. VDI guideline 3787. Part 2. Berlin: Beuth. (1998).

Google Scholar

[15] A. Matzarakis, F. Rutz, H. Mayer. Modelling radiation fluxes in simple and complex environments - application of the RayMan model. International Journal of Biometeorology. 51: 323–34. (2007).

DOI: 10.1007/s00484-006-0061-8

Google Scholar

[16] S.G. Miao, W.M. Jiang, X.Y. Wang, et al. Impact assessment of urban meteorology and the atmospheric environment using urban sub-domain planning. Boundary Layer Meteorology. 118(1): 133-150. (2006).

DOI: 10.1007/s10546-005-5292-4

Google Scholar