scholarly journals Heat-Mitigation Strategies to Improve Pedestrian Thermal Comfort in Urban Environments: A Review

2020 ◽  
Vol 12 (23) ◽  
pp. 10000
Author(s):  
Nazanin Nasrollahi ◽  
Amir Ghosouri ◽  
Jamal Khodakarami ◽  
Mohammad Taleghani
Keyword(s):  
Thermal Comfort ◽  
Climatic Factors ◽  
Urban Environments ◽  
Mitigation Strategies ◽  
Comfort Level ◽  
Outdoor Thermal Comfort ◽  
Factors Affecting ◽  
Urban Forms ◽  
Radiant Temperature ◽  
The Impact

Thermal comfort is one of the main factors affecting pedestrian health, and improving thermal comfort enhances walkability. In this paper, the impact of various strategies on thermal-comfort improvement for pedestrians is thoroughly evaluated and compared. Review studies cover both fieldwork and simulation results. These strategies consist of shading (trees, buildings), the orientation and geometry of urban forms, vegetation, solar-reflective materials, and water bodies, which were investigated as the most effective ways to improve outdoor thermal comfort. Results showed that the most important climatic factors affecting outdoor thermal comfort are mean radiant temperature, wind speed, and wind direction in a microclimate. The best heat-mitigation strategy for improving thermal comfort was found to be vegetation and specifically trees because of their shading effect. The effect of height-to-width (H/W) ratio in canyons is another important factor. By increasing H/W ratio, the thermal-comfort level also increases. Deploying highly reflective materials in urban canyons is not recommended, as several studies showed that they could reflect solar radiation onto pedestrians. Results also showed that, in order to achieve a satisfactory level of thermal comfort, physiological and psychological factors should be considered together.

scholarly journals Impact of Urban Vegetation on Outdoor Thermal Comfort: Comparison between a Mediterranean City (Lecce, Italy) and a Northern European City (Lahti, Finland)

Forests ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 228 ◽  
Author(s):  
Elisa Gatto ◽  
Riccardo Buccolieri ◽  
Eeva Aarrevaara ◽  
Fabio Ippolito ◽  
Rohinton Emmanuel ◽  
...  
Keyword(s):  
Thermal Comfort ◽  
Green Infrastructure ◽  
Urban Environments ◽  
Outdoor Thermal Comfort ◽  
European City ◽  
Northern European ◽  
Alternative Scenarios ◽  
Radiant Temperature ◽  
The Impact ◽  
Mediterranean City

This paper is devoted to the application of the modelling approach, as one of the methods for the evaluation of thermal comfort, to neighborhoods located in two cities characterized by a different climate, i.e., a Mediterranean city in southern Italy (Lecce) and a northern European city in southern Finland (Lahti). The impact of the presence of vegetation in both places is evaluated and compared, further considering alternative scenarios for thermal comfort improvement. The thermal comfort condition is expressed in terms of indices (mean radiant temperature (MRT) and predicted mean vote (PMV)). Results show that at pedestrian level the presence of vegetation lead to an improvement of thermal comfort in summer of about 2 points in both neighborhoods. This improvement is also evident observing the spatial distribution of MRT with a difference of 7 °C in the Lecce neighborhood and 3 °C in Lahti. In winter, thermal discomfort is observed in the presence of vegetation with a difference of 1.3 °C in the Lecce neighborhood and 1.5 °C in Lahti in terms of MRT. However, trees and green cover have the important potential to offset climate change impact and to make urban environments less thermally stressful. This study aims to guide urban planners towards a motivated and necessary transaction towards new green infrastructure whose effect should, however, be analyzed and investigated case by case.

Implications of Building Material Choice on Outdoor Microclimate for Sustainable Built Environment

2015 ◽  
Vol 650 ◽  
pp. 82-90 ◽  
Author(s):  
D. Kannamma ◽  
A. Meenatchi Sundaram
Keyword(s):  
Thermal Comfort ◽  
Building Material ◽  
Building Materials ◽  
Climatic Factors ◽  
Outdoor Environment ◽  
Outdoor Thermal Comfort ◽  
Physical Factors ◽  
Physiological Equivalent Temperature ◽  
Material Choice ◽  
The Impact

The climatic conditions in a man-made urban environment may differ appreciably from those in the surrounding natural or rural environs.... each urban man-made buildings, roads, parking area, factories......creates around and above it a modified climate with which it interacts [1].Outdoor thermal comfort has gained importance in thermal comfort studies especially in tropical countries. In country like India, culturally the activities are spread both indoors and outdoors. Therefore the need for ambient outdoor environment gains importance. As there are many factors that contribute to outdoor thermal comfort (climatic factors and physical factors), this study aims in analyzing the impact of building material contribution, in an institutional courtyard. In order to understand the thermal contribution of various building materials and to suggest material choice to designers, ENVIMET is used for simulation purpose. The outdoor thermal comfort index employed in this study is PET (Physiological Equivalent Temperature), calibrated using RAYMAN.

scholarly journals The most problematic variable in the course of human-biometeorological comfort assessment — the mean radiant temperature

2011 ◽  
Vol 3 (1) ◽  
Author(s):  
Noémi Kántor ◽  
János Unger
Keyword(s):  
Thermal Comfort ◽  
Short Wave ◽  
Urban Environments ◽  
Outdoor Thermal Comfort ◽  
Radiation Environment ◽  
Wave Radiation ◽  
Mean Radiant Temperature ◽  
Radiation Fluxes ◽  
The Mean ◽  
Radiant Temperature

AbstractThis paper gives a review on the topic of the mean radiant temperature Tmrt, the most important parameter influencing outdoor thermal comfort during sunny conditions. Tmrt summarizes all short wave and long wave radiation fluxes reaching the human body, which can be very complex (variable in spatial and also in temporal manner) in urban settings. Thermal comfort researchers and urban planners need easy and sound methodological approaches to assess Tmrt. After the basics of the Tmrt calculation some of the methods suitable for obtaining Tmrt also in urban environments will be presented.. Two of the discussed methods are based on instruments which measure the radiation fluxes integral (globe thermometer, pyranometer-pyrgeometer combination), and three of the methods are based on modelling the radiation environment with PC software (RayMan, ENVI-met and SOLWEIG).

Towards Pedestrian Microclimatic Comfort: A Rapid Predication Model for Street Winds and Pedestrian Thermal Sensation

Nano LIFE ◽  
2018 ◽  
Vol 08 (02) ◽  
pp. 1840006
Author(s):  
Jing Li ◽  
Mengnan Qi ◽  
Qiuhua Duan ◽  
Lei Huo ◽  
Julian Wang
Keyword(s):  
Wind Speed ◽  
Built Environment ◽  
Thermal Comfort ◽  
Air Temperature ◽  
Goodness Of Fit ◽  
Comfort Level ◽  
Outdoor Thermal Comfort ◽  
Design Parameters ◽  
Rapid Urbanization ◽  
The Impact

Significant changes in the urban built environment have occurred due to rapid urbanization and increases in the urban population. Such alterations may produce environmental health-related issues such as urban heat stress, air pollution and traffic noise. This research undertook a field study to collect data including urban design parameters, micro-environmental factors and city climatic information. This work was conducted over a two-year period on three pedestrian streets located in high-density urban areas in Beijing. These areas were selected in order to study the influences of urban street canyon texture within a particular geometric layout, wind flow corridors and variations in air temperature on pedestrian microclimatic comfort. The results will facilitate the work of urban planners by providing them with information for use in improving outdoor thermal comfort through their designs. A total of 60[Formula: see text]485 samples were organized into training, validation and test sets. We confirmed our hypothesis that internal wind speed ([Formula: see text] is attributable mainly to the urban texture coefficient ([Formula: see text], air temperature ([Formula: see text] and leading-in wind speed ([Formula: see text]. The model was tested using the test data collected onsite, which demonstrated a very accurate goodness-of-fit; the model achieved an R-squared value of 0.82, which meant that [Formula: see text] as a dependent variable was 82% correlated to the three predictors as independent variables. With this computer simulation, urban planners can now predict and visualize the impact of changes on the built environment in terms of either the direction of solar radiation received or increases in wind speed, in return for the desired thermal comfort level for residents of the neighborhood.

scholarly journals Evaluasi Kenyamanan Termal Ruang Sekolah SMA Negeri di Kota Padang

2016 ◽  
Vol 12 (1) ◽  
pp. 310 ◽  
Author(s):  
Lusi Susanti ◽  
Nike Aulia
Keyword(s):  
Thermal Comfort ◽  
Climatic Factors ◽  
Thermal Conditions ◽  
Comfort Level ◽  
Air Humidity ◽  
Student Body ◽  
Predicted Mean Vote ◽  
Individual Vote ◽  
The Individual ◽  
Radiant Temperature

This research aims to determine thermal conditions and sensation of thermal comfort in classrooms of high schools in Padang. This study was conducted in 11 State Senior High School (SMA) represented 11 districts in Padang. About 10% of total student body in each schools were participated in this study to vote thermal comfort questioners. To determine thermal comfort level in this study, PMV (Predicted mean Vote) and PPD (Predicted Percentage of dissatisfied) method were used according to standard of thermal comfort in ASHRAE 55-2005 and ISO 7730. PMV method is used to determine scope of situation in the environment that scaled from +3 for very hot until -3 for very cold, and PPD is a method to calculate the number of human (in percentage) dissatisfied with the environment. Calculated PMV and PPD were compared with PMV and PPD resulted from individual vote from questionnaires. Result showed that in general, thermal conditions in classrooms had air temperature and radiant temperature from 27oC – 30oC, air humidity from 68% - 80%, and wind speed of 0 m/s. Calculated PMV from this condition were ranging from +1 slightly warm) until +2 (warm) while PPD calculated greater than 20%. Compared with calculated PMV and PPD values, the individual vote showed values from +0,5 (neutral) until +1 (slightly warm) while PPD values of individual vote greater than 20% except for SMA 2 and SMA 11 Padang. It is concluded that improvements of indoor thermal conditions have to make inside classrooms as well as landscape outside in order to improve thermal comfort level of students during learning and teaching.Keywords: Thermal Comfort, PMV (Predicted Mean Vote), PPD (Predicted Percentage ofDissatisfied), climatic factors, SMA

Thermomodernization of the school and change of the level of thermal comfort

2021 ◽  
pp. 62-74
Author(s):  
V. Deshko ◽  
◽  
N. Buyak ◽  
I. Bilous ◽  
◽  
...  
Keyword(s):  
Energy Consumption ◽  
Thermal Comfort ◽  
Comfort Level ◽  
Mean Radiant Temperature ◽  
Before And After ◽  
Change In The Mean ◽  
The Mean ◽  
Energy Audits ◽  
Radiant Temperature ◽  
The Impact

The paper highlights the topical issue of ensuring the appropriate thermal comfort level and reducing energy consumption by public buildings. Thermal modernization, in turn, allows increasing the level of thermal comfort, which is not taken into account and evaluated in practice, although the relevant standards for comfort conditions and categories of buildings to ensure comfort have been introduced in Ukraine. The aim of the study is to analyze the impact of thermal modernization on the level of energy consumption and thermal comfort. The paper analyzes the change in the level of comfort before and after thermal modernization, defines the comfortable conditions category of the building, presents the change in the mean radiant temperature, as one of the main factors of PMV change in these conditions. PMV has been found to vary from -0.7 in the cold months to 0.2 in the off-season. Changing the thermal resistance can increase the PMV. The wall of the S orientation is characterized by larger fluctuations of PMV, which is due to the inflow of solar radiation and as a consequence of increasing the mean room radiant temperature. The change in the value of energy consumption is analyzed, the class of energy efficiency and the category for providing comfortable conditions are determined. Such an approach on the example of a real building is an example for conducting energy audits and certification taking into account comfort indicators.

Public Housing in Bandung an Assessment and Approaches through Urban Physics

2014 ◽  
Vol 935 ◽  
pp. 273-276 ◽  
Author(s):  
Beta Paramita ◽  
Hiroatsu Fukuda
Keyword(s):  
Thermal Comfort ◽  
Public Housing ◽  
Urban Form ◽  
High Density ◽  
Outdoor Thermal Comfort ◽  
Humid Climate ◽  
Urban Forms ◽  
Hot Humid Climate ◽  
Radiant Temperature

High density of population and vertical buildings seems to be the only aspect fit to the concept for city in the developing country. The vertical housings then become a matter of necessity in high density area, in which the building groups themselves significantly contribute to microclimate at urban scales. This study is going to give descriptions of outdoor thermal comfort of public housing in Bandung by means its correlation between urban forms and mean radiant temperature. A number of simulations have used ENVI-met to reveal a better urban form which addresses the role of urban physics in the study of outdoor thermal comfort in a hot humid climate area.

scholarly journals Urban Heat Islands and Thermal Comfort: A Case Study of Zorrotzaurre Island in Bilbao

2021 ◽  
Vol 13 (11) ◽  
pp. 6106
Author(s):  
Irantzu Alvarez ◽  
Laura Quesada-Ganuza ◽  
Estibaliz Briz ◽  
Leire Garmendia
Keyword(s):  
Thermal Comfort ◽  
Heat Waves ◽  
Urban Environments ◽  
Urban Heat Islands ◽  
Extreme Weather Events ◽  
Climate Index ◽  
Physiological Equivalent Temperature ◽  
Heat Islands ◽  
The North ◽  
The Impact

This study assesses the impact of a heat wave on the thermal comfort of an unconstructed area: the North Zone of the Island of Zorrotzaurre (Bilbao, Spain). In this study, the impact of urban planning as proposed in the master plan on thermal comfort is modeled using the ENVI-met program. Likewise, the question of whether the urbanistic proposals are designed to create more resilient urban environments is analyzed in the face of increasingly frequent extreme weather events, especially heat waves. The study is centered on the analysis of temperature variables (air temperature and average radiant temperature) as well as wind speed and relative humidity. This was completed with the parameters of thermal comfort, the physiological equivalent temperature (PET) and the Universal Temperature Climate Index (UTCI) for the hours of the maximum and minimum daily temperatures. The results demonstrated the viability of analyzing thermal comfort through simulations with the ENVI-met program in order to analyze the behavior of urban spaces in various climate scenarios.

scholarly journals Modeling Mean Radiant Temperature Distribution in Urban Landscapes Using DART

2021 ◽  
Vol 13 (8) ◽  
pp. 1443
Author(s):  
Maria Angela Dissegna ◽  
Tiangang Yin ◽  
Hao Wu ◽  
Nicolas Lauret ◽  
Shanshan Wei ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Thermal Comfort ◽  
Leaf Area ◽  
Remote Sensing Data ◽  
Outdoor Thermal Comfort ◽  
Transfer Model ◽  
Mean Radiant Temperature ◽  
Area Index ◽  
Sensing Data ◽  
Radiant Temperature

The microclimatic conditions of the urban environment influence significantly the thermal comfort of human beings. One of the main human biometeorology parameters of thermal comfort is the Mean Radiant Temperature (Tmrt), which quantifies effective radiative flux reaching a human body. Simulation tools have proven useful to analyze the radiative behavior of an urban space and its impact on the inhabitants. We present a new method to produce detailed modeling of Tmrt spatial distribution using the 3-D Discrete Anisotropic Radiation Transfer model (DART). Our approach is capable to simulate Tmrt at different scales and under a range of parameters including the urban pattern, surface material of ground, walls, roofs, and properties of the vegetation (coverage, shape, spectral signature, Leaf Area Index and Leaf Area Density). The main advantages of our method are found in (1) the fine treatment of radiation in both short-wave and long-wave domains, (2) detailed specification of optical properties of urban surface materials and of vegetation, (3) precise representation of the vegetation component, and (4) capability to assimilate 3-D inputs derived from multisource remote sensing data. We illustrate and provide a first evaluation of the method in Singapore, a tropical city experiencing strong Urban Heat Island effect (UHI) and seeking to enhance the outdoor thermal comfort. The comparison between DART modelled and field estimated Tmrt shows good agreement in our study site under clear-sky condition over a time period from 10:00 to 19:00 (R2 = 0.9697, RMSE = 3.3249). The use of a 3-D radiative transfer model shows promising capability to study urban microclimate and outdoor thermal comfort with increasing landscape details, and to build linkage to remote sensing data. Our methodology has the potential to contribute towards optimizing climate-sensitive urban design when combined with the appropriate tools.

Impact of climatic conditions on the parameters of failure flow of military vehicles

2021 ◽  
pp. 095440702110202
Author(s):  
Nikolaj Dobrzinskij ◽  
Algimantas Fedaravicius ◽  
Kestutis Pilkauskas ◽  
Egidijus Slizys
Keyword(s):  
Climatic Factors ◽  
Armed Forces ◽  
Climatic Conditions ◽  
Operating Conditions ◽  
Technical Equipment ◽  
Factors Affecting ◽  
Military Vehicles ◽  
Equipment Reliability ◽  
Number Of Factors ◽  
The Impact

Relevance of the article is based on participation of armed forces in various operations and exercises, where reliability of machinery is one of the most important factors. Transportation of soldiers as well as completion of variety of tasks is ensured by properly functioning technical equipment. Reliability of military vehicles – armoured SISU E13TP Finnish built and HMMWV M1025 USA built were selected as the object of the article. Impact of climatic conditions on reliability of the vehicles exploited in southwestern part of the Atlantic continental forest area is researched by a case study of the vehicles exploitation under conditions of the climate of Lithuania. Reliability of military vehicles depends on a number of factors such as properties of the vehicles and external conditions of their operation. Their systems and mechanisms are influenced by a number of factors that cause different failures. Climatic conditions represent one of the factors of operating load which is directly dependent on the climate zone. Therefore, assessment of the reliability is started with the analysis of climatic factors affecting operating conditions of the vehicles. Relationship between the impact of climatic factors and failure flow of the vehicles is presented and discussed.

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