scholarly journals Post-occupancy evaluation of outdoor thermal comfort in hot arid zone

2020 ◽  
Author(s):  
Rawan Shawesh ◽  
Mady Mohamed
Keyword(s):  
Thermal Comfort ◽  
Arid Zone ◽  
Objective Assessment ◽  
Subjective Assessment ◽  
Outdoor Thermal Comfort ◽  
Thermal Indices ◽  
Physiological Equivalent Temperature ◽  
Post Occupancy Evaluation ◽  
Physical Measurements ◽  
Globe Temperature

Abstract Human comfort and healthy environments lie at the core of every debate about outdoor spaces nowadays. Thermal comfort is a vital concern for planners and designers in order to produce a healthy and thermally comfortable environment, since the influence of different climates and user groups has been found to greatly alter the range of responses for thermal comfort calculations. This requires Post-Occupancy Evaluation (POE) with an integration of the appropriate outdoor thermal comfort (OTC) index. This paper presents the results of a detailed assessment for the OTC in hot arid zone (HAZ) using the most suitable thermal index. A case study was selected from Effat Campus, Jeddah, Saudi Arabia, to represent the HAZ. Subjective assessment employed the physiological equivalent temperature (PET) and the predictive mean vote (PMV) thermal indices in analysing the results of online and self-directed questionnaires while objective assessment employed a hand-held anemometer that was used to measure wind speed, whereas the wet bulb globe temperature (WBGT) SD Card Logger with a black globe thermometer 75 mm in diameter and emissivity of 0.95 was used to measure the globe temperature. The physical measurements were later used to calculate the mean radiant temperature (MRT) and consequently the PET index using RayMan Software. The results confirmed the significance of the shading strategy on OTC. The study revealed that there is no percentage as shading is permitting people to use the space; otherwise, in hot arid zone, the space would be completely unusable under the sun while the PET is more suitable than the PMV index.

Numerical Study of Thermal Comfort with the Effects of Canopy Transparency

2014 ◽  
Vol 919-921 ◽  
pp. 1677-1680
Author(s):  
Choul Woong Kwon ◽  
Sung Woo Shin
Keyword(s):  
Thermal Comfort ◽  
Urban Areas ◽  
Thermal Environment ◽  
Numerical Study ◽  
Complex Surface ◽  
Outdoor Thermal Comfort ◽  
Thermal Indices ◽  
Physiological Equivalent Temperature ◽  
Thermal Index ◽  
Radiation Fluxes

Several complex thermal indices (e.g. PMV and PET) were developed in the last decades to describe the quantify the thermal environment of humans and the energy fluxes between body and environment. Compared to open spaces the complex surface structure of urban areas creates an environment with special microclimatic characteristics, which have a dominant effect on the energy balance of the human body. In this study, outdoor thermal comfort conditions are examined through numerical model with different transparency ratios in canopy. The intensity of radiation fluxes is dependent on several factors, such as orientation, size and transparency of canopy. Special emphasis is given to the human-biometeorological assessment of the microclimate of building element (canopy) through the application of the thermal index PET (Physiological Equivalent Temperature). The analysis is carried out by the utilization of Ecotect and RayMan software.

scholarly journals Outdoor Thermal Comfort Analysis in a Cold Continental Climate: The Case of a Pedestrian-Only Street in Downtown Toronto

2021 ◽  
Author(s):  
Christopher Marleau
Keyword(s):  
Thermal Comfort ◽  
Thermal Sensation ◽  
Computer Software ◽  
Thermal Conditions ◽  
Field Investigation ◽  
Outdoor Thermal Comfort ◽  
Thermal Indices ◽  
Physiological Equivalent Temperature ◽  
Weather Patterns ◽  
Continental Climate

Increased interest in urban thermal comfort has emerged in recent years with unpredictable weather patterns and unprecedented temperature extremes around the world. Urban modelling computer software can help with understanding interactions between built environment and microclimates. However, results of simulations can be difficult to interpret if acceptable thermal conditions for a location are unknown. Using a compound approach of field investigation and microclimate modelling for a pedestrian-only street in Toronto, Canada, this study investigates urban outdoor thermal comfort (OTC) in a cold continental climate. Four thermal indices were used to analyze field data and the results were compared with OTC research conducted in other climates. In this study, the Physiological Equivalent Temperature (PET) provided the strongest annual correlation with the pedestrian thermal sensation votes. A PET comfort range between 9°C and 24°C was found. Survey results were then used to interpret the simulated effect of urban vegetation within the case study microclimate during a summer scenario.

scholarly journals Outdoor Thermal Comfort Analysis in a Cold Continental Climate: The Case of a Pedestrian-Only Street in Downtown Toronto

2021 ◽  
Author(s):  
Christopher Marleau
Keyword(s):  
Thermal Comfort ◽  
Thermal Sensation ◽  
Computer Software ◽  
Thermal Conditions ◽  
Field Investigation ◽  
Outdoor Thermal Comfort ◽  
Thermal Indices ◽  
Physiological Equivalent Temperature ◽  
Weather Patterns ◽  
Continental Climate

Increased interest in urban thermal comfort has emerged in recent years with unpredictable weather patterns and unprecedented temperature extremes around the world. Urban modelling computer software can help with understanding interactions between built environment and microclimates. However, results of simulations can be difficult to interpret if acceptable thermal conditions for a location are unknown. Using a compound approach of field investigation and microclimate modelling for a pedestrian-only street in Toronto, Canada, this study investigates urban outdoor thermal comfort (OTC) in a cold continental climate. Four thermal indices were used to analyze field data and the results were compared with OTC research conducted in other climates. In this study, the Physiological Equivalent Temperature (PET) provided the strongest annual correlation with the pedestrian thermal sensation votes. A PET comfort range between 9°C and 24°C was found. Survey results were then used to interpret the simulated effect of urban vegetation within the case study microclimate during a summer scenario.

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 Assessing The Thermal Comfort Conditions In Open Spaces: A Transversal Field Survey On The University Campus In India

2021 ◽  
Vol 8 (3) ◽  
pp. 77-92
Author(s):  
Pardeep Kumar ◽  
Amit Sharma
Keyword(s):  
Thermal Comfort ◽  
Air Temperature ◽  
Arid Regions ◽  
Thermal Sensation ◽  
Probit Analysis ◽  
Outdoor Thermal Comfort ◽  
Cold Weather ◽  
Open Spaces ◽  
Physiological Equivalent Temperature ◽  
Preferred Temperature

Outdoor thermal comfort (OTC) promotes the usage frequency of public places, recreational activities, and people's wellbeing. Despite the increased interest in OTC research in the past decade, less attention has been paid to OTC research in cold weather, especially in arid regions. The present study investigates the OTC conditions in open spaces at the campus area in the arid region. The study was conducted by using subjective surveys(questionnaire) and onsite monitoring (microclimate parameters). The study was conducted at the Deenbandhu Chhotu Ram University of Science and Technology, Murthal, Haryana-India campus during the cold season of 2019. The timings of surveys were between 9:00 and 17:00 hours. The authors processed the 185 valid questionnaire responses of the respondents to analyze OTC conditions. Only 8.6% of the respondents marked their perceived sensation "Neutral." Regression analysis was applied between respondents' thermal sensations and microclimate parameters to develop the empirical thermal sensation model. The air temperature was the most dominant parameter affecting the sensations of the respondents. The empirical model indicated that by increasing air temperature, relative humidity, and solar radiation, the thermal sensations also increased while wind speed had an opposite effect. Physiological equivalent temperature (PET) was applied for assessing the OTC conditions; the neutral PET range was found to be 18.42-25.37°C with a neutral temperature of 21.89°C. The preferred temperature was 21.99 °C by applying Probit analysis. The study's findings could provide valuable information in designing and planning outdoor spaces for educational institutions in India's arid regions

Outdoor thermal comfort in a tropical coastal tourist resort in Haikou, China

2019 ◽  
Vol 29 (5) ◽  
pp. 730-745 ◽  
Author(s):  
Chunjing Shang ◽  
Xinyu Huang ◽  
Yufeng Zhang ◽  
Maoquan Chen
Keyword(s):  
Solar Radiation ◽  
Thermal Comfort ◽  
Thermal Sensation ◽  
Outdoor Thermal Comfort ◽  
Survey Period ◽  
Physiological Equivalent Temperature ◽  
Local Climate ◽  
Acceptable Range ◽  
Tropical Areas ◽  
Autumn And Winter

Considering the importance of thermal comfort in decision-making in tourism, a transverse study involving micrometeorological measurements and questionnaires was performed at a popular coastal destination during the seasons of spring, autumn and winter. We examined the thermal sensation and thermal acceptability using the physiological equivalent temperature (PET). The results indicate that tourists’ thermal sensations varied with the season and the neutral PETs were 19.2°C, 23.8°C and 23.3°C in winter, spring and autumn. The 90% acceptable ranges of the PET affected by the local climate were 19.6–29.5°C during the entire three-season survey period, 21.4–27.1°C in the spring, 19.2–32°C in the autumn and more than 15.9°C in the winter. The analysis of microclimate parameters that affect thermal comfort in three seasons reveals that people expected weaker solar radiation, stronger wind and lower humidity with the air temperature rising, and vice versa. The acceptable range of wind speed was 0.6–2.5 m/s in winter, 0.6–3.5 m/s in spring and autumn. The acceptable range of solar radiation was 0–150 W/m2 in autumn and 0–250 W/m2 in winter. These findings contribute to the better designs for coastal facilities and the thermal comfort of tropical areas.

scholarly journals Thermal Comfort Assessment and Heat-Related Illnesses among Sellers in Periodic Local Markets: A Case Study in Hot and Dry Climate of Iran

2021 ◽  
Author(s):  
Hoda Rahimifard ◽  
Hamidreza Heidari ◽  
Abolfazl Mohamadbeigi ◽  
Ahmad Soltanzadeh ◽  
Mohsen Mahdinia ◽  
...  
Keyword(s):  
Thermal Comfort ◽  
Environmental Parameters ◽  
Thermal Conditions ◽  
Tympanic Temperature ◽  
Thermal Indices ◽  
Local Conditions ◽  
Environmental Indices ◽  
Local Markets ◽  
Hot Climate ◽  
Globe Temperature

Background:This study aims to evaluate the thermal conditions of periodic local markets and determine the thermal comfort and sensation of sellers, as well as the prevalence of heat-related diseases in the hot and dry climate of Iran. Methods:In this study, thermal comfort and sensation of 330 sellers from periodic markets in Qom city, a dry and hot climate in Iran, were evaluated. Measurements were performed for 15 days, from July 16 to August 1. To assess environmental thermal condition, wet bulb globe temperature (WBGT) index and discomfort index (DI) were determined, and participants' tympanic temperature was determined to consistency assessment with thermal indices. Finally, the effects of environmental, personal, and working conditions on the prevalence of heat-related diseases among sellers were determined. Results:The environmental indices, including DI and WBGT index, had the most association with heat-related illnesses and tympanic temperature (P<0.05). The sellers perceived the environmental conditions as warm to hot after 1:00 pm. Besides, they expressed an uncomfortable or very uncomfortable situation after 12:00 pm. The findings showed that environmental parameters play a more important role in the prevalence of heat-related diseases and heat strain than individual and occupational factors. Conclusion:The sellers may be at risk of heat stress in outdoor markets in nearly half of the workday in the summer months. Therefore, it is very important that these people receive the necessary training in the prevention of heat illness in order to take appropriate protective measures in accordance with local conditions.

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 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 PAIR INFLUENCE OF WIND SPEED AND MEAN RADIANT TEMPERATURE ON OUTDOOR THERMAL COMFORT OF HUMID TROPICAL ENVIRONMENT

2017 ◽  
Vol 10 (2) ◽  
pp. 177-185 ◽  
Author(s):  
Sangkertadi Sangkertadi ◽  
Reny Syafriny
Keyword(s):  
Wind Speed ◽  
Thermal Comfort ◽  
Significant Role ◽  
Tropical Environment ◽  
Outdoor Thermal Comfort ◽  
Regression Equations ◽  
Mean Radiant Temperature ◽  
Walking Activity ◽  
Globe Temperature ◽  
Radiant Temperature

The purposes of this article is to explore knowledge of outdoor thermal comfort in humid tropical environment for urban activities especially for people in walking activity, and those who stationary/seated with moderate action. It will be characterized the pair influence of wind speed and radiant temperature on the outdoor thermal comfort. Many of researchers stated that those two microclimate variables give significant role on outdoor thermal comfort in tropical humid area. Outdoor Tropical Comfort (OTC) model was used for simulation in this study. The model output is comfort scale that refers on ASHRAE definition. The model consists of two regression equations with variables of air temperature, globe temperature, wind speed, humidity and body posture, for two types of activity: walking and seated. From the results it can be stated that there is significant role of wind speed to reduce mean radiant temperature and globe temperature, when the velocity is elevated from 0.5 m/s to 2 m/s. However, the wind has not play significant role when the speed is changed from 2 m/s to 3.5 m/s. The results of the study may inspire us to implement effectiveness of electrical-fan equipment for outdoor space in order to get optimum wind speed, coupled with optimum design of shading devices to minimize radiant temperature for thermal comfort.

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