The Impact of Sky View Factor on Pedestrian Thermal Comfort in Tropical Context: A Case of Jakarta Sidewalk

2021 ◽  
pp. 27-33
Author(s):  
Victorina Arif ◽  
Lin Yola
Keyword(s):  
Thermal Comfort ◽  
View Factor ◽  
Sky View Factor ◽  
The Impact

scholarly journals In-situ Measurement of Pedestrian Outdoor Thermal Comfort in Universities Campus of Malaysia

2019 ◽  
Author(s):  
Nurnida Elmira Othman ◽  
Sheikh Ahmad Zaki ◽  
Nurul Huda Ahmad ◽  
Azli Razak
Keyword(s):  
Thermal Comfort ◽  
Field Measurement ◽  
Thermal Sensation ◽  
Outdoor Thermal Comfort ◽  
View Factor ◽  
Thermal Preference ◽  
Equivalent Temperature ◽  
Physiological Equivalent Temperature ◽  
Sky View Factor

The present study is intended to evaluate an outdoor thermal comfort at two universities campus in Malaysia. Field measurement and questionnaire survey were conducted simultaneously to assess the microclimatic condition and pedestrian thermal sensation. A total of 3033 samples were collected at seven different sky view factor (SVF) values that range from 0.2 to 0.9. The physiological equivalent temperature (PET) was estimated to evaluate outdoor thermal comfort. It was observed that at a highly shaded area (SVF < 0.35) the respondent’s thermal sensation vote (TSV) are neutral (> 25%), acceptable for thermal acceptance vote (TAV) (> 50%) and no change (> 50%) for thermal preference vote (TPV). For moderate shaded (0.35 ≤ SVF ≤ 0.70) TSV was voted as hot (> 25%), acceptable for TAV (40%), and prefer slightly cooler for TPV (>50%). For less shaded area (0.70 < SVF ≤ 1), TSV was voted as hot and very hot (> 25%), acceptable for TAV (>40%) and prefer slightly cooler for TPV (> 40%). Moreover, the PET value increases simultaneously with the increase of SVF. Results thus suggest that at any given activities such as sitting, walking, and standing also caused effects slightly on the way people thermally perceive it during the on-campus daytime.

scholarly journals A Numerical Study on the Correlation between Sky View Factor and Summer Microclimate of Local Climate Zones

Atmosphere ◽  
2019 ◽  
Vol 10 (8) ◽  
pp. 438 ◽  
Author(s):  
Tong Lyu ◽  
Riccardo Buccolieri ◽  
Zhi Gao
Keyword(s):  
Wind Speed ◽  
Thermal Comfort ◽  
Numerical Study ◽  
Local Effect ◽  
Urban Morphology ◽  
View Factor ◽  
Urban Microclimate ◽  
Local Climate ◽  
Sky View Factor ◽  
Local Climate Zones

In the context of urbanization, research on urban microclimate and thermal comfort has become one of the themes of eco-city design. Sky view factor (SVF), one of the parameters of urban spatial form, combines multiple morphological information, such as plane opening, aspect ratio, and building density and has an important impact on the urban microclimate. However, there is still no clear research conclusion on the correlation between SVF and microclimate. In this paper, nine Local Climate Zone (LCZ) models are used and typical summer meteorological conditions of Nanjing are applied as an attempt to partially fill this gap. The calculated microclimate and thermal comfort indices include air temperature (AT), surface temperature (ST), relative humidity (RH), wind speed (WS), mean radiant temperature (MRT), and predicted mean vote (PMV). Results show that the local effect of urban morphology on thermal comfort can be retrieved from the use of comprehensive parameters such as SVF (which takes into account the building height, layout, and density) whose distribution in the investigated models showed to be correlated with MRT, so did PMV under low wind speed conditions.

scholarly journals Sky View Factor (SVF) assessment in a real-time system for thermal comfort conditions monitoring in the Moscow region

2020 ◽  
Vol 611 ◽  
pp. 012061
Author(s):  
A A Perkhurova ◽  
M I Varentsov ◽  
T E Samsonov ◽  
P E Kargashin ◽  
P A Korosteleva ◽  
...  
Keyword(s):  
Thermal Comfort ◽  
Real Time ◽  
Moscow Region ◽  
View Factor ◽  
Time System ◽  
Real Time System ◽  
Sky View Factor

scholarly journals The Influence of Sky View Factor on Daytime and Nighttime Urban Land Surface Temperature in Different Spatial-Temporal Scales: A Case Study of Beijing

2021 ◽  
Vol 13 (20) ◽  
pp. 4117
Author(s):  
Qiang Chen ◽  
Qianhao Cheng ◽  
Yunhao Chen ◽  
Kangning Li ◽  
Dandan Wang ◽  
...  
Keyword(s):  
Surface Temperature ◽  
Land Surface Temperature ◽  
Land Surface ◽  
Thermal Environment ◽  
Experimental Results ◽  
View Factor ◽  
Temporal Scales ◽  
Building Height ◽  
Sky View Factor ◽  
The Impact

Urban building morphology has a significant impact on the urban thermal environment (UTE). The sky view factor (SVF) is an important structure index of buildings and combines height and density attributes. These factors have impact on the land surface temperature (LST). Thus, it is crucial to analyze the relationship between SVF and LST in different spatial-temporal scales. Therefore, we tried to use a building vector database to calculate the SVF, and we used remote sensing thermal infrared band to retrieve LST. Then, we analyzed the influence between SVF and LST in different spatial and temporal scales, and we analyzed the seasonal variation, day–night variation, and the impact of building height and density of the SVF–LST relationship. We selected the core built-up area of Beijing as the study area and analyzed the SVF–LST relationship in four periods in 2018. The temporal experimental results indicated that LST is higher in the obscured areas than in the open areas at nighttime. In winter, the maximum mean LST is in the open areas. The spatial experimental results indicate that the SVF and LST relationship is different in the low SVF region, with 30 m and 90 m pixel scale in the daytime. This may be the shadow cooling effect around the buildings. In addition, we discussed the effects of building height and shading on the SVF–LST relationship, and the experimental results show that the average shading ratio is the largest at 0.38 in the mid-rise building area in winter.

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

2014 ◽  
Vol 1065-1069 ◽  
pp. 2927-2930 ◽  
Author(s):  
Bai Chuan Ma ◽  
Qi Sang ◽  
Ji Feng Gou
Keyword(s):  
Thermal Comfort ◽  
Field Experiments ◽  
Meteorological Data ◽  
Thermal Conditions ◽  
Central Business District ◽  
Outdoor Thermal Comfort ◽  
View Factor ◽  
Thermal Environments ◽  
Sky View Factor ◽  
Business District

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.

scholarly journals Sky view factor and thermal comfort analysis using hemispheric images from Google Street View and wavelet in an urban ecosystem of the Brazilian Cerrado

2018 ◽  
Vol 40 ◽  
pp. 26
Author(s):  
Angela Fatima da Rocha ◽  
Ernany Paranaguá da Silva ◽  
Carlo Ralph de Musis ◽  
Marta Cristina de Albuquerque Nogueira
Keyword(s):  
Thermal Comfort ◽  
Air Temperature ◽  
View Factor ◽  
Brazilian Cerrado ◽  
Physiological Equivalent Temperature ◽  
Mato Grosso ◽  
Google Street View ◽  
Sky View Factor ◽  
Street View ◽  
Temperature And Humidity

This article aims to analyse the sky view factor (SVF) in one of the hottest cities of the Brazilian Cerrado, and its correlation with thermal comfort in two urban sections with different characteristics, as well as the physiological equivalent temperature (PET) and predicted mean vote (PMV) indices, complemented by a characterisation in the frequency field for a 12-month cut-off in the same year of relative air temperature and humidity. The study area was located in the central region of Cuiabá, Mato Grosso, due to the presence of regions with high urbanisation indices and small parks; one section composed of afforested area and second section composed of varied buildings. To obtain the SVF, the Google Street View image database was used, from which fisheye images were reconstructed and the SVF was determined using  RayMan  software. The PET and PMV indices were determined for the morning, afternoon, and evening, with comfort in the morning and discomfort in the afternoon and evening. Traditional Morlet wavelets were plotted for time series of relative air temperature and humidity for the year 2015, which qualitatively demonstrated some of the dynamics of these micrometeorological variables for tropical Cerrado climate.

scholarly journals Correlating the Sky View Factor with the Pedestrian Thermal Environment in a Hot Arid University Campus Plaza

2021 ◽  
Vol 13 (2) ◽  
pp. 468
Author(s):  
Randa Osama Shata ◽  
Ayman Hassaan Mahmoud ◽  
Mohammad Fahmy
Keyword(s):  
Thermal Environment ◽  
Field Measurements ◽  
Urban Trees ◽  
View Factor ◽  
University Campus ◽  
Physiological Equivalent Temperature ◽  
Area Index ◽  
Comfort Index ◽  
Sky View Factor ◽  
The Impact

In hot, arid regions on university campuses, students are more vulnerable to heat stresses than in street canyons in terms of function; however, the knowledge of the impact of built environments on thermal performance is still lacking. In two summer and winter days, the shading effect of the existing urban trees pattern in a university campus in Egypt was examined to correlate their Sky View Factor (SVF) with the thermal environment, meteorology, Physiological Equivalent Temperature (PET), and Universal Thermal Comfort Index (UTCI). The ENVI-met model was used in order to assess meteorological parameters, followed by SVF calculation in the Rayman program. Meteorological field measurements validated the simulation model and measured the Leaf Area Index (LAI) of two native urban trees to model the in-situ canopies foliage. In summer, the results showed a significant direct impact of the SVF on mean radiant temperature (Tmrt), PET, and UTCI; however, the excessive shading by trees on materials with a low albedo and low wind speed could lead to a slight increase in air temperature. Meanwhile, in the winter, SVF did not affect the microclimatic variables, PET, or UTCI. The resulting insight into the correlation between SVF and Tmrt emphasizes the importance of urban trees in modifying the microclimates of already-existing university plazas.

Sign in / Sign up

Export Citation Format

Share Document