A tropical field study on outdoor bioclimatic comfort of people with different thermal histories

Several studies reported that the long-term thermal history of the human body affects its thermal comfort and preferences. We conducted a tropical field study in Sanya city, China; 1512 questionnaires were collected from tourists. The tourists had five thermal histories associated with five different climate regions (cold, severely cold, hot summer, cold winter, hot summer and warm winter and temperate regions). Our results showed that the human body's long-term thermal history had distinct influences on their thermal sensation, thermal comfort and preferences at their destination. Greater difference in a subject's thermal history from that of the tourist destination showed greater difference in the bioclimatic comfort and thermal preference. The neutral physiological equivalent temperature (nPET) of tourists with thermal histories in the severely cold and cold regions was 25.6°C and 25.9°C, respectively. The nPET was 1.4°C and 1.7°C higher than that of the temperate regions, respectively. The relationship between thermal acceptability vote and thermal comfort vote showed that the tourists with thermal histories in the severely cold and cold regions were more sensitive to environmental changes than those with histories from the other regions.

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Outdoor Thermal Comfort at a University Campus: Studies from Personal and Long-Term Thermal History Perspectives

Sustainability ◽

10.3390/su12219284 ◽

2020 ◽

Vol 12 (21) ◽

pp. 9284

Author(s):

Jiao Xue ◽

Xiao Hu ◽

Shu Nuke Sani ◽

Yuanyuan Wu ◽

Xinyu Li ◽

...

Keyword(s):

Thermal Comfort ◽

Thermal History ◽

Thermal Environment ◽

Thermal Sensation ◽

Cold Climate ◽

Outdoor Thermal Comfort ◽

Climate Index ◽

University Campus ◽

Winter Climate

Thermally comfortable outdoor spaces have contributed to high-quality urban living. In order to provide a further understanding of the influences of gender and long-term thermal history on outdoor thermal comfort, this study conducted field surveys at a university campus in Shanghai, China by carrying out microclimatic monitoring and subjective questionnaires from May to October, 2019. The analysis of collected data found that, during our survey, 57% of the occupants felt comfortable overall and 40–60% of them perceived the microclimate variables (air temperature, humidity, solar radiation, and wind speed) as “neutral”. The universal thermal climate index (UTCI) provided a better correlation with occupant thermal sensation than the physiologically equivalent temperature (PET). Females were more sensitive to the outdoor thermal environment than males. Older age led to lower thermal sensation, but the thermal sensitivities for age groups of <20, 20–50, and >50 were similar. Occupants who had resided in Shanghai for a longer period showed higher overall comfort rating and lower thermal sensation. Interviewees who came from hot summer and cold winter climate regions were less effected by the change of UTCI than those from severe cold or cold climate regions.

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An Interactive Task Conditioning System Featuring Personal Comfort Models and Non-Intrusive Sensing Techniques: A Field Study in Shanghai

Technologies ◽

10.3390/technologies9040090 ◽

2021 ◽

Vol 9 (4) ◽

pp. 90

Author(s):

Siliang Lu ◽

Erica Cochran Hameen

Keyword(s):

Thermal Comfort ◽

Field Study ◽

Air Temperature ◽

Indoor Air ◽

Thermal Environment ◽

Thermal Sensation ◽

New Paradigm ◽

Dynamic Task ◽

Current Task ◽

Open Plan

Heating, ventilation and air-conditioning (HVAC) systems play a key role in shaping office environments. However, open-plan office buildings nowadays are also faced with problems like unnecessary energy waste and an unsatisfactory shared indoor thermal environment. Therefore, it is significant to develop a new paradigm of an HVAC system framework so that everyone could work under their preferred thermal environment and the system can achieve higher energy efficiency such as task ambient conditioning system (TAC). However, current task conditioning systems are not responsive to personal thermal comfort dynamically. Hence, this research aims to develop a dynamic task conditioning system featuring personal thermal comfort models with machine learning and the wireless non-intrusive sensing system. In order to evaluate the proposed task conditioning system performance, a field study was conducted in a shared office space in Shanghai from July to August. As a result, personal thermal comfort models with indoor air temperature, relative humidity and cheek (side face) skin temperature have better performances than baseline models with indoor air temperature only. Moreover, compared to personal thermal satisfaction predictions, 90% of subjects have better performances in thermal sensation predictions. Therefore, personal thermal comfort models could be further implemented into the task conditioning control of TAC systems.

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

International Journal of Built Environment and Sustainability ◽

10.11113/ijbes.v8.n3.786 ◽

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

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The Evaluation of Outdoor Thermal Sensation and Outdoor Energy Efficiency of a Commercial Pedestrianized Zone

Energies ◽

10.3390/en12071324 ◽

2019 ◽

Vol 12 (7) ◽

pp. 1324 ◽

Cited By ~ 3

Author(s):

Xuan Ma ◽

Hiroatsu Fukuda ◽

Dian Zhou ◽

Mengying Wang

Keyword(s):

Energy Efficiency ◽

Thermal Comfort ◽

Open Space ◽

Thermal Sensation ◽

Heat Island ◽

Physiological Equivalent Temperature ◽

Winter Climate ◽

Coverage Ratio ◽

Urban Heat ◽

The Relationship

The growth of the scale of cities intensifies urban heat island (UHI) by obstructing the wind and building more radiation at pedestrian level, thus leading to an energy consumption. Commercial pedestrianized-zones cannot only become symbols of cities but also an important factor increasing local economic income. This study conducts on-site measurement and numerical simulation to evaluate the cooling energy efficiency of different parameters (building, vegetation, pavement material) in Fo Shan city, which locates in hot-summer and warm-winter climate region of China. Also, calculations are done to evaluate the index physiological equivalent temperature (PET) for understanding thermal sensation at a pedestrian level (1.5 m). To evaluate different impacts of this zone renewal on the environment and choose the most energy-saving method, it is easy for us to utilize the linear regression for understanding the relationship between coverage ratio of trees (TCR) and thermal comfort in canyon space, which shows that ∆PET = 0.1703 × TCR + 0.2444 with a most important R2 value of 0.9836, for TCR increases from 12.5% to 22%. In open space, also increasing coverage ratio of trees (TCR) can effectively improve humans’ thermal comfort, which shows that ∆PET = 0.2644 × TCR + 0.3955 with a most important R2 value of 0.8892.

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Influence of long-term thermal history on thermal comfort and preference

Energy and Buildings ◽

10.1016/j.enbuild.2019.109685 ◽

2020 ◽

Vol 210 ◽

pp. 109685 ◽

Cited By ~ 8

Author(s):

Mina Jowkar ◽

Richard de Dear ◽

James Brusey

Keyword(s):

Thermal Comfort ◽

Thermal History

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

Indoor and Built Environment ◽

10.1177/1420326x19862337 ◽

2019 ◽

Vol 29 (5) ◽

pp. 730-745 ◽

Cited By ~ 1

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.

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Interactive effect between long-term and short-term thermal history on outdoor thermal comfort: Comparison between Guangzhou, Zhuhai and Melbourne

The Science of The Total Environment ◽

10.1016/j.scitotenv.2020.144141 ◽

2021 ◽

Vol 760 ◽

pp. 144141

Author(s):

Cho Kwong Charlie Lam ◽

Yanping Gao ◽

Hongyu Yang ◽

Taihan Chen ◽

Yong Zhang ◽

...

Keyword(s):

Thermal Comfort ◽

Thermal History ◽

Interactive Effect ◽

Outdoor Thermal Comfort ◽

Short Term

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

KnE Social Sciences ◽

10.18502/kss.v3i21.4998 ◽

2019 ◽

Cited By ~ 1

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.

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Winter Thermal Comfort and Perceived Air Quality: A Case Study of Primary Schools in Severe Cold Regions in China

Energies ◽

10.3390/en13225958 ◽

2020 ◽

Vol 13 (22) ◽

pp. 5958

Author(s):

Fusheng Ma ◽

Changhong Zhan ◽

Xiaoyang Xu ◽

Guanghao Li

Keyword(s):

Air Quality ◽

Primary School ◽

Thermal Comfort ◽

Indoor Air ◽

Primary Schools ◽

Natural Ventilation ◽

Thermal Sensation ◽

School Buildings ◽

Heating Season ◽

Cold Regions

In Northeast China, most classrooms in primary and secondary schools still use natural ventilation during cold days in winter. This study investigated the thermal comfort and the perceived air quality of children in primary schools in severe cold regions in China. Field measurements were conducted in four typical primary classrooms in two naturally ventilated teaching buildings in the winter of 2016 in the provincial city of Shenyang. Six field surveys were distributed to 141 primary students aged 8 to 11, and 835 valid questionnaires were collected. The results showed that the indoor temperature and the daily mean CO2 concentrations of the primary school classrooms ranged from 17.06 to 24.29 °C and from 1701 to 3959 ppm, respectively. The thermal neutral temperature of the primary school students was 18.5 °C, and the 90% thermal comfort temperature ranged from 17.3 to 20.1 °C. Children were able to respond to changes in indoor air quality, but there was no significant correlation between the children’s perceptions of air quality and the carbon dioxide levels in the classroom. In general, children have a lower comfort temperature than adults. In addition, children are more sensitive to temperature changes during the heating season than adults. Due to differences in thermal sensation between children and adults, the current thermal comfort standard based on adult data is not applicable to primary school buildings and children. The air quality evaluation during heating season indicates that it is necessary to add indoor air environment monitoring instruments and purification equipment to the naturally ventilated classrooms. At present and in the future, more research based on children’s data is needed to solve the indoor air environment problems in primary school buildings.

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