Digital Simulation for the Outdoor Thermal Comfort Assessment

2019 ◽  
pp. 33-46 ◽  
Author(s):  
Alshimaa Aboelmakarem Farag ◽  
Sama Badawi ◽  
Rahma M. Doheim
Keyword(s):  
Thermal Comfort ◽  
Digital Simulation ◽  
Objective Assessment ◽  
Simulation Method ◽  
Outdoor Thermal Comfort ◽  
Thermal Environments ◽  
Subjective Perceptions ◽  
Outdoor Spaces ◽  
Pros And Cons ◽  
The City

Creating a successful public outdoor space for the city people is significantly affected by the sensation of thermal comfort, which is influenced by the local microclimate. With the increase in the complexity of the urban environment and the excessive change in the climate, there is a great need to quantitatively assess the thermal comfort in outdoor spaces to help designers and decision makers to establish the optimum scenario from the first stages of design. The traditional methods of assessment have been criticized for dependency on people's subjective perceptions and responses to different thermal environments. This chapter aims to explore the potentials and limitations of the “Digital Simulation” as one of the methods that allow objective assessment. This chapter tackles several related issues and discusses researchers' recent attempts and contributions, which would help the readers to understand the pros and cons of using the digital simulation method in outdoor thermal comfort assessment and proposes possible solutions for several challenges.

scholarly journals The Contribution of Urban Morphology to the Formation of the Microclimate in Compact Urban Cores: A Study in the City Center of Thessaloniki

Urban Science ◽  
2021 ◽  
Vol 5 (2) ◽  
pp. 37
Author(s):  
Georgios-Rafail Kouklis ◽  
Athena Yiannakou
Keyword(s):  
Field Study ◽  
Urban Form ◽  
Simulation Method ◽  
Urban Morphology ◽  
Green Spaces ◽  
City Center ◽  
Outdoor Spaces ◽  
Microclimatic Conditions ◽  
The Relationship ◽  
The City

The purpose of this paper is to investigate the contribution of urban morphology to the formation of microclimatic conditions prevailing within urban outdoor spaces. We studied the compact form of a city and examined, at a detailed, street plan level, elements related to air temperature, urban ventilation, and the individual’s thermal comfort. All elements examined are directly affected by both the urban form and the availability of open and green spaces. The field study took place in a typical compact urban fabric of an old city center, the city center of Thessaloniki, where we investigated the relationship between urban morphology and microclimate. Urban morphology was gauged by examining the detailed street plan, along with the local building patterns. We used a simulation method based on the ENVI-met© software. The findings of the field study highlight the fact that the street layout, the urban canyon, and the open and green spaces in a compact urban form contribute decisively both to the creation of the microclimatic conditions and to the influence of the bioclimatic parameters.

scholarly journals Thermal Comfort Simulation on Cik Ditiro Corridor

2019 ◽  
Vol 46 (1) ◽  
pp. 67-78
Author(s):  
Septian Eka Prayoga ◽  
Arif Kusumawanto
Keyword(s):  
Land Use ◽  
Thermal Comfort ◽  
Urban Areas ◽  
Rapid Development ◽  
Thermal Conditions ◽  
Simulation Method ◽  
Surface Material ◽  
Climate Variable ◽  
The City ◽  
Research Show

Surface materials that turn into hard surface material and lack of vegetations are some of the effects of rapid development that can affect the micro climate in urban areas. This happened on Cik Ditiro corridor in the city of Yogyakarta which had quite dense activities, this was marked by various functions of land use and human activities throughout the day. The method is simulation method that uses the EnviMET 4.0 software and the empirical measurements. This method is to simulate the value of each climate variable in existing conditions and ideal conditions. The results of this research show that the condition of the Cik Ditiro corridor still belongs to the heat which is uncomfortable thermal conditions. Recommendations result of this research is to make better thermal comfort on corridor. The result of this research to give recommendations in terms of improving better for thermal comfort.

Study on Design Strategies for Improving Outdoor Thermal Comfort in the Cold Regions of China

2011 ◽  
Vol 250-253 ◽  
pp. 3798-3801 ◽  
Author(s):  
Jing Li ◽  
Yu Liu
Keyword(s):  
Thermal Comfort ◽  
North China ◽  
Outdoor Environment ◽  
Outdoor Thermal Comfort ◽  
Design Strategies ◽  
Cold Regions ◽  
Winter Climate ◽  
Thermal Environments ◽  
The North ◽  
Xi’An City

Along with the improvement of dwelling quality, the length of time and frequency of outdoor activities in winter greatly increase in the north China area, although the outdoor thermal environments are still unsatisfactory. It is necessary for both planners and architects to improve outdoor thermal environments in the cold regions of north China. This paper firstly introduces the general winter climate features in some north China cities. Then, it takes Xi'an city as an example to show the shortage of uncomfortable outdoor environment. Thirdly, the design strategies to improve outdoors thermal comfort include wind and snow protection, sunlight usage, environmental zones and recreational facilities, etc. are discussed.

scholarly journals Analyzing the Effect of Water Body on the Thermal Environment and Comfort at Indoor and Outdoor Spaces in Tropical University Campus

2021 ◽  
Vol 12 (10) ◽  
pp. 282-288
Author(s):  
Farhadur Reza ◽  
◽  
Shoichi Kojima ◽  
Wataru Ando
Keyword(s):  
Thermal Comfort ◽  
Thermal Environment ◽  
Outdoor Thermal Comfort ◽  
University Campus ◽  
Clothing Insulation ◽  
Comfort Index ◽  
Outdoor Spaces ◽  
Globe Temperature ◽  
And Performance ◽  
University Spaces

Water bodies play a significant role in its surrounding thermal environment. Thermal comfort in university spaces is critical that affects the students’ health and performance as well as the staffs. This study investigated thermal environment and comfort near lakeside and non-lakeside tropical university spaces. Standard Effective Temperature (SET*) have been calculated using recorded air temperature, relative humidity, globe temperature, air velocity, clothing insulation and metabolic rate to evaluate the thermal comfort in outdoor and indoor spaces. The effects of weather parameters have been clearly visible on the comfort index. The calculated SET* values indicate that the outdoor thermal comfort near a lake is much closer to the standard comfort zone than non-lakeside outdoor space. In the case of indoor thermal comfort, however, slightly a different scenario has been observed. To achieve the desirable indoor thermal environment, some design considerations are recommended based on findings.

scholarly journals What is the most threatening for citizens of a mid-latitude city: cold stress or heat stress?

2021 ◽  
Author(s):  
Sara Top ◽  
Dragan Milošević ◽  
Steven Caluwaerts ◽  
Stevan Savić
Keyword(s):  
Heat Stress ◽  
Cold Stress ◽  
Thermal Comfort ◽  
Heat Wave ◽  
Outdoor Thermal Comfort ◽  
Belgian Society ◽  
Human Thermal Comfort ◽  
Summer Heat ◽  
Heat And Cold Stress ◽  
The City

<p>Both heat and cold waves cause extreme human thermal discomfort and a clear excess in mortality. This shows the importance of knowing the prevailing thermal comfort conditions and how thermal comfort conditions vary in various environments so measures can be taken. Microclimatic and outdoor human thermal comfort conditions are investigated in various built-up and green areas in the city of Ghent (Belgium) using meteorological measurements of six weather stations of the MOCCA (Monitoring the Cities Climate and Atmosphere) network in combination with calculations done by RayMan.</p><p>Normal to extreme summer heat wave periods show that dangerous strong heat stress prevails during the daytime periods at all locations. Comparison of thermal comfort during normal and extreme summer heat wave periods showed that heat stress is more extreme when a heat wave is more intense. Overall the urban park in Ghent was the most comfortable location during heat waves since it effectively mitigates heat stress in the city. These results should be taken into account in urban planning and design to keep mid-latitude cities livable.</p><p>Further, a one year data series revealed that outdoor cold stress was more apparent during 2017 in the mid-latitude city of Ghent that experiences a mild maritime climate. During spring and summer, both heat stress and cold stress occurred due to the larger diurnal temperature range compared to the other seasons. Even though high Physiological Equivalent Temperatures (PET) were obtained during a heat wave in summer, heat stress did not occur as intensely and as frequently compared to cold stress on annual level. It could thus be stated that outdoors, cold stress is a bigger threat than heat stress. However, one should keep in mind that the study was executed for outdoor thermal heat comfort and that people will take shelter or take measures when feeling uncomfortable. The question is thus rather, how are citizens protected against heat and cold stress? Currently, the Belgian society is better adapted to cold stress since most buildings contain central heating, while air conditioning is not standard. Future projections predict an increase in temperature, causing more occurrence of extreme heat stress, while extreme cold stress will be reduced. Additionally, the urban heat island effect currently has mainly a positive effect on the average annual outdoor thermal comfort conditions, while it will become a negative effect in the warmer future. Measures should thus be taken to reduce the threat of future heat stress.</p>

scholarly journals Outdoor Thermal Comfort Optimization through Vegetation Parameterization: Species and Tree Layout

2021 ◽  
Vol 13 (21) ◽  
pp. 11791
Author(s):  
Bouthaina Sayad ◽  
Djamel Alkama ◽  
Redha Rebhi ◽  
Younes Menni ◽  
Hijaz Ahmad ◽  
...  
Keyword(s):  
Numerical Simulation ◽  
Solar Radiation ◽  
Thermal Comfort ◽  
Atmospheric Model ◽  
Outdoor Thermal Comfort ◽  
Maximum Reduction ◽  
Palm Trees ◽  
Outdoor Spaces ◽  
Ficus Nitida

The optimization of outdoor thermal comfort has become the keystone to guarantee the healthy and comfortable use of outdoor spaces. This study aims to optimize the outdoor thermal comfort through vegetation parameterization in a boulevard located in Guelma city, Algeria during summertime. However, two main parameters were investigated, species and tree layout, through a numerical simulation. We first collected microclimate data of a sunny summer day. Second, we used real microclimate data in different simulations using the Envi-met atmospheric model. The findings reveal that Ficus Nitida is the most significant species to intercept solar radiation and provide shade over the day in Souidani Boudjemaa Boulevard, with a maximum reduction of Ta = 0.3 °C and UTCI = 2.6 °C at 13:00 p.m. Tree layout is a determining parameter in the creation of shaded paths, based on the quality of the shadows cast by the trees, namely, their size. Thereby, planting the washingtonia palm trees along the center of the boulevard is the best option to maximize the shaded area within the boulevard, with maximum reduction of Ta = 1.8 °C and UTCI = 3.5 °C at 16:00 p.m.

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 How to Improve the Liveability in Cities: The Effect of Urban Morphology and Greening on Outdoor Thermal Comfort

2021 ◽  
Vol 65 (2-4) ◽  
pp. 361-370
Author(s):  
Guglielmina Mutani ◽  
Valeria Todeschi ◽  
Simone Beltramino
Keyword(s):  
Built Environment ◽  
Thermal Comfort ◽  
Energy Savings ◽  
Green Roofs ◽  
Urban Morphology ◽  
Outdoor Thermal Comfort ◽  
Water Runoff ◽  
Physiological Equivalent Temperature ◽  
The Impact ◽  
The City

Extensive and intensive green roofs and vegetated walls should be used to improve the livability in cities, especially in densely built-up context, in order to optimize their contribution on energy savings and greenhouse gas emissions, improving thermal comfort conditions and ensuring a greater storm-water runoff. The aim of this study is to evaluate the effect of urban morphology and to quantify the impact of green surfaces and plants on outdoor thermal comfort conditions. The analysis was applied to six neighborhoods in the city of Turin, identified as typical districts with different building geometries, urban contexts and green presence. The outdoor thermal comfort conditions were assessed calculating a set of indicators, such as the predicted mean vote and the physiological equivalent temperature, with the support of ENVI-met tool. Retrofit scenarios were hypothesized, and outdoor thermal comfort conditions were investigated before and after the installation of green roofs and vegetated areas. The result allowed to understand how thermal comfort vary, considering the building geometry, urban morphology, and green areas in different zones of the city of Turin. By analyzing neighborhoods, it is possible to identify the optimal built environment that ensure better thermal comfort conditions. These models and tools could support urban planners in defining the best measures to improve the liveability and quality in the built environment considering local constraints and the real characteristics of the territory or in designing new neighborhoods.

Sign in / Sign up

Export Citation Format

Share Document