scholarly journals Thermal Environment Map in Street Canyon for Implementing Extreme High Temperature Measures

Atmosphere ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 550
Author(s):  
Hideki Takebayashi ◽  
Mai Okubo ◽  
Hiroki Danno
Keyword(s):  
High Temperature ◽  
Street Canyon ◽  
Thermal Environment ◽  
Detailed Calculation ◽  
Mean Radiant Temperature ◽  
The North ◽  
Environment Map ◽  
Extreme High Temperature ◽  
Typical Summer ◽  
Radiant Temperature

The thermal environment map in street canyon is derived by using GIS building data and more detailed calculation, and its effectiveness is considered for implementing extreme high temperature measures. The influence of mean radiant temperature (MRT) is more dominant than the wind velocity on the distribution of standard new effective temperature (SET*) on the typical summer day in street canyon in the urban area of Kobe city, and the solar radiation shading is more effective in suppressing the rise of SET* in the daytime than improving the land coverage. The following strategy of extreme high temperature measures is derived by considering the thermal environment map in street canyon. Pedestrians may find the shaded places on the north-south road until 10:00 a.m. and after 3:00 p.m., due to the eastern building’s shade in the morning and the western building’s shade in the afternoon.

scholarly journals How Can We Adapt Thermal Comfort for Disabled Patients? A Case Study of French Healthcare Buildings in Summer

Energies ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4530
Author(s):  
Youcef Bouzidi ◽  
Zoubayre El Akili ◽  
Antoine Gademer ◽  
Nacef Tazi ◽  
Adil Chahboun
Keyword(s):  
Thermal Comfort ◽  
Thermal Environment ◽  
Residential Buildings ◽  
Linear Regression Analysis ◽  
Environmental Parameters ◽  
Physical Parameters ◽  
Mean Radiant Temperature ◽  
Operative Temperature ◽  
Neutral Temperature ◽  
Radiant Temperature

This paper investigates adaptive thermal comfort during summer in medical residences that are located in the French city of Troyes and managed by the Association of Parents of Disabled Children (APEI). Thermal comfort in these buildings is evaluated using subjective measurements and objective physical parameters. The thermal sensations of respondents were determined by questionnaires, while thermal comfort was estimated using the predicted mean vote (PMV) model. Indoor environmental parameters (relative humidity, mean radiant temperature, air temperature, and air velocity) were measured using a thermal environment sensor during the summer period in July and August 2018. A good correlation was found between operative temperature, mean radiant temperature, and PMV. The neutral temperature was determined by linear regression analysis of the operative temperature and Fanger’s PMV model. The obtained neutral temperature is 23.7 °C. Based on the datasets and questionnaires, the adaptive coefficient α representing patients’ capacity to adapt to heat was found to be 1.261. A strong correlation was also observed between the sequential thermal index n(t) and the adaptive temperature. Finally, a new empirical model of adaptive temperature was developed using the data collected from a longitudinal survey in four residential buildings of APEI in summer, and the obtained adaptive temperature is 25.0 °C with upper and lower limits of 24.7 °C and 25.4 °C.

scholarly journals Thermal Environment Design of Outdoor Spaces by Examining Redevelopment Buildings Opposite Central Osaka Station

Climate ◽  
2019 ◽  
Vol 7 (12) ◽  
pp. 143 ◽  
Author(s):  
Hideki Takebayashi
Keyword(s):  
Solar Radiation ◽  
Wind Velocity ◽  
Thermal Environment ◽  
Heat Budget ◽  
Environment Design ◽  
Building Shape ◽  
Outdoor Spaces ◽  
Outdoor Space ◽  
Typical Summer ◽  
Radiant Temperature

Thermal environmental design in an outdoor space is discussed by focusing on the proper selection and arrangement of buildings, trees, and covering materials via the examination of redevelopment buildings in front of Central Osaka Station, where several heat island countermeasure technologies have been introduced. Surface temperatures on the ground and wall were calculated based on the surface heat budget equation in each 2 m size mesh of the ground and building wall surface. Incident solar radiation was calculated using ArcGIS and building shape data. Mean radiant temperature (MRT) of the human body was calculated using these results. Distribution of wind velocity was calculated by computational fluid dynamics (CFD) reproducing buildings, obstacles, trees, and the surroundings. The effect of MRT on SET* was greater than that of wind velocity at 13:00 and 17:00 on a typical summer day. SET* reduction was the highest by solar radiation shading, followed by surface material change and ventilation. The largest ratio of the area considered for the thermal environment was 83% on Green Garden, which consists of 44% of building shade, 21% of tree shade, 7% of water surface, and 11% of green cover. It is appropriate to consider the thermal environment design of outdoor space in the order of shade by buildings, shading by trees, and improvement of surface materials.

A multilayer mean radiant temperature model for pedestrians in a street canyon with trees

2018 ◽  
Vol 141 ◽  
pp. 298-309 ◽  
Author(s):  
Chae Yeon Park ◽  
Dong Kun Lee ◽  
E. Scott Krayenhoff ◽  
Han Kyul Heo ◽  
Saekyul Ahn ◽  
...  
Keyword(s):  
Street Canyon ◽  
Temperature Model ◽  
Mean Radiant Temperature ◽  
Radiant Temperature

On the measurement of the mean radiant temperature and its influence on the indoor thermal environment assessment

2013 ◽  
Vol 63 ◽  
pp. 79-88 ◽  
Author(s):  
Francesca Romana d’Ambrosio Alfano ◽  
Marco Dell’Isola ◽  
Boris Igor Palella ◽  
Giuseppe Riccio ◽  
Aldo Russi
Keyword(s):  
Thermal Environment ◽  
Mean Radiant Temperature ◽  
Indoor Thermal Environment ◽  
Environment Assessment ◽  
The Mean ◽  
Radiant Temperature

The Effect of Urban Design on Outdoor Thermal Environment in a Central Business District Area in Singapore

2014 ◽  
Vol 1073-1076 ◽  
pp. 1428-1432
Author(s):  
Wei Yang ◽  
Yao Lin Lin ◽  
Nyuk Hien Wong
Keyword(s):  
Numerical Simulation ◽  
Urban Design ◽  
Air Temperature ◽  
Thermal Environment ◽  
Central Business District ◽  
Width Ratio ◽  
Mean Radiant Temperature ◽  
Outdoor Thermal Environment ◽  
Business District ◽  
Radiant Temperature

Outdoor thermal environment in urban spaces is important for people to enjoy the urban environment. This paper investigated the effect of urban design on outdoor thermal environment in an urban street in the central business district in Singapore, focusing on street orientation and height-to-width ratio. The microclimatic parameters of different street design scenarios were determined by ENVI-met numerical simulation. Field measurement was conducted to validate the results from the numerical simulation and they were in good agreement. For different design scenarios, it is found that (1) The air temperature differences did not exceed 0.8°C; (2) The mean radiant temperature differences could exceed 40°C; (3) The maximum wind speed difference was 0.6 m/s; (4) No distinct relative humidity differences could be found. The results show that shading is the key strategy for improving outdoor thermal environment in Singapore because it leads to reduction on the air temperature and mean radiant temperature simultaneously. N-S orientated street had the best thermal environment condition.Outdoor thermal environment in urban spaces is important for people to enjoy the urban environment. This paper investigated the effect of urban design on outdoor thermal environment in an urban street in the central business district in Singapore, focusing on street orientation and height-to-width ratio. The microclimatic parameters of different street design scenarios were determined by ENVI-met numerical simulation. Field measurement was conducted to validate the results from the numerical simulation and they were in good agreement. For different design scenarios, it is found that (1) The air temperature differences did not exceed 0.8°C; (2) The mean radiant temperature differences could exceed 40°C; (3) The maximum wind speed difference was 0.6 m/s; (4) No distinct relative humidity differences could be found. The results show that shading is the key strategy for improving outdoor thermal environment in Singapore because it leads to reduction on the air temperature and mean radiant temperature simultaneously. N-S orientated street had the best thermal environment condition. Shading achieved by means of high aspect ratios can improve thermal environment at street level.

Differents Methods to Estimate the Mean Radiant Temperature in an Urban Canyon

2013 ◽  
Vol 650 ◽  
pp. 647-651 ◽  
Author(s):  
R. de Lieto Vollaro ◽  
A. Vallati ◽  
S. Bottillo
Keyword(s):  
Human Body ◽  
Street Canyon ◽  
The Other ◽  
Radiation Environment ◽  
Mean Radiant Temperature ◽  
Radiation Fluxes ◽  
Human Energy ◽  
Environment Simulation ◽  
The Mean ◽  
Radiant Temperature

The mean radiant temperature is one of the meteorological key parameters governing human energy balance and the thermal comfort of human body. This variable can be considered as the sum of all direct and reflected radiation fluxes to which the human body is exposed. After the basics of the Tmrt calculation a comparison between two methods suitable for obtaining Tmrt in a street canyon will be presented. One of the discussed methods of obtaining Tmrt is based on the utilization of a globe thermometer. The other method is the radiation environment simulation through three PC software (RayMan, ENVI-met and SOLWEIG).

scholarly journals Evaluation and modelling the micro-bioclimatological conditions of a popular playground in Szeged, Hungary

2013 ◽  
Vol 4 (1) ◽  
pp. 57-61 ◽  
Author(s):  
L. A. Égerházi ◽  
N. Kántor ◽  
T. Gál
Keyword(s):  
Land Cover ◽  
Thermal Comfort ◽  
Meteorological Parameters ◽  
Thermal Sensation ◽  
Thermal Conditions ◽  
Radiation Environment ◽  
Mean Radiant Temperature ◽  
Predicted Mean Vote ◽  
Typical Summer ◽  
Radiant Temperature

Abstract This paper presents a thermal comfort study of a popular playground in Szeged, Hungary in order to find its optimal land cover and vegetation options. For this assessment simulated micro- and bioclimatological conditions recorded on a typical summer day (12th July 2011) were analysed. The thermal and radiation features of the study area were quantified by two biometeorological indices, Predicted Mean Vote (PMV) and Mean Radiant Temperature (Tmrt). For the simulation of the meteorological parameters and the bioclimate indices, ENVI-met microclimate model was used. The results confirmed that the modelled areas with different land cover provide a variety of thermal conditions for the visitors; moreover, human thermal sensation was significantly affected by the change of the radiation environment.

scholarly journals SIMULATION OF THE INFLUENCE OF VEGETATION ON MICROCLIMATE AND THERMAL COMFORT IN THE CITY OF SÃO PAULO

2019 ◽  
Vol 3 (2) ◽  
pp. 1 ◽  
Author(s):  
Jörg Spangenberg ◽  
Paula Shinzato ◽  
Erik Johansson ◽  
Denise Duarte
Keyword(s):  
Thermal Comfort ◽  
Street Canyon ◽  
Sao Paulo ◽  
City Centre ◽  
São Paulo ◽  
Mean Radiant Temperature ◽  
Speed Up ◽  
The Mean ◽  
Radiant Temperature ◽  
The City

The microclimates of a park, a square and a street canyon were measured on a summer day in the city centre of São Paulo, Brazil. The field monitoring showed that the park was up to 2°C cooler than the square and the canyon. The effect of adding shading trees to the street canyon was simulated for the same day using the numerical model ENVI-met. The simulations showed that incorporating street trees in the urban canyon had a limited cooling effect on the air temperature (up to 1.1°C), but led to a significant cooling of the street surface (up to 12°C) as well as a great reduction of the mean radiant temperature at pedestrian height (up to 24°C). Although the trees lowered the wind speed up to 45% of the maximum values, the thermal comfort was improved considerably as the physiologically equivalent temperature (PET) was reduced by up to 12°C.

scholarly journals The Effect of Street Orientation on Outdoor Thermal Comfort in a Cold Mountainous Climate

2021 ◽  
Author(s):  
Narges Delpak ◽  
Hassan Sajadzadeh ◽  
Saide Hasanpourfard ◽  
Farshid Aram
Keyword(s):  
Thermal Comfort ◽  
Urban Spaces ◽  
Outdoor Thermal Comfort ◽  
Mean Radiant Temperature ◽  
Direct Sunlight ◽  
Physiological Equivalent Temperature ◽  
The North ◽  
Radiant Temperature ◽  
Climatic Characteristics ◽  
New Settlements

Lack of due attention to the orientation of streets and establishment of urban blocks without regard for climatic characteristics and conditions of the environment have an adverse effect on thermal comfort in open urban spaces. Construction of new settlements without taking into account climatic requirements undermines thermal comfort for pedestrians and other users, especially in cold regions. Considering the coldness of the region under study and the significance of the orientation of streets in absorbing radiation and providing heat to outdoor urban spaces, this study investigates the effect of the orientation of streets on microclimatic comfort in one of the residential towns of Hamadan City in Iran. For this purpose, microclimate simulation was performed using ENVI-met software. A residential block with four different orientations (the most common orientations of its surrounding buildings) were simulated in the coldest day of winter and the hottest day of summer. The results suggest that streets have different thermal behavior in different orientations. Orientation affects mean radiant temperature (Tmrt), the duration of exposure to direct sunlight, wind speed, and physiological equivalent temperature (PET), which are all important factors in thermal comfort. Based on these findings, north-south streets in Hamedan receive more radiant temperature during winter compared to other simulated orientations and provide more desirable thermal comfort. The average PET value on a winter day at a point on the north-south passage was 4.5-8 °C warmer than other orientations. In summer, streets with intercardinal orientations (i.e., northeast-southwest and northwest-southeast) provided the lowest PET (about 2 °C cooler than other orientations) and better thermal comfort

scholarly journals Assessing the Impacts of Extreme Climate Events on Vegetation Activity in the North South Transect of Eastern China (NSTEC)

Water ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 2291
Author(s):  
Zhou ◽  
Pei ◽  
Xia ◽  
Wu ◽  
Zhong ◽  
...  
Keyword(s):  
High Temperature ◽  
Eastern China ◽  
Terrestrial Vegetation ◽  
Extreme Climate Events ◽  
Extreme Climate ◽  
The North ◽  
Extreme High Temperature ◽  
Vegetation Activity ◽  
Extreme Cold ◽  
Climate Events

Extreme climate events frequently exert serious effects on terrestrial vegetation activity. However, these effects are still uncertain in widely distributed areas with different climate zones. Transect analysis is important to understand how terrestrial vegetation responds to climate change, especially extreme climate events, by substituting space for time. In this paper, seven extreme climate indices and the Normalized Difference Vegetation Index (NDVI) are employed to examine changes in the extreme climate events and vegetation activity. To reduce the uncertainty of the NDVI, two satellite-derived NDVI datasets, including the third generation Global Inventory Monitoring and Modeling System (GIMMS-3g) NDVI dataset and the NDVI from the National Oceanic and Atmospheric Administration (NOAA) satellites on Star Web Servers (SWS), were employed to capture changes in vegetation activity. The impacts of climate extremes on vegetation activity were then assessed over the period of 1982–2012 using the North–South Transect of Eastern China (NSTEC) as a case. The results show that vegetation activity was overall strengthened from 1982 to 2012 in the NSTEC. In addition, extreme high temperature events revealed an increased trend of approximately 5.15 days per decade, while a weakened trend (not significant) was found in extreme cold temperature events. The strengthened vegetation activities could be associated with enhanced extreme high temperature events and weakened extreme cold temperature events over the past decades in most of the NSTEC. Despite this, inversed changes were also found locally between vegetation activity and extreme climate events (e.g., in the Northeast Plain). These phenomena could be associated with differences in vegetation type, human activity, as well as the combined effects of the frequency and intensity of extreme climate events. This study highlights the importance of accounting for the vital roles of extreme climate effects on vegetation activity.

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