Thermal Comfort and Thermal Sensation During Exposure to Hot, Hot-Humid and Thermoneutral Environments

Thermal comfort is crucial in satisfaction and maintaining quality sleep for occupants. In this study, we investigated the comfort temperature in the bedroom at night and sleep quality for Indonesian students during summer and winter. Eighteen male Indonesian students aged 29 ± 4 years participated in this study. The participants had stayed in Japan for about six months. We evaluated the sleep parameters using actigraphy performed during summer and winter. All participants completed the survey regarding thermal sensation, physical conditions, and subjective sleepiness before sleep. The temperature and relative humidity of participants’ bedrooms were also measured. We found that the duration on the bed during winter was significantly longer than that during summer. However, sleeping efficiency during winter was significantly worse than that during summer. The bedroom temperature of the participants was in the range of comfort temperature in Indonesia. With the average bedroom air temperature of 22.2 °C, most of the participants still preferred “warm” and felt “slightly comfortable” during winter. The average comfort temperature each season calculated using the Griffiths method was 28.1 °C during summer and 23.5 °C during winter. In conclusion, differences in adaptive action affect bedroom thermal conditions. Furthermore, habits encourage the sleep performance of Indonesian students.

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Predicted Medium Vote Thermal Comfort Analysis Applying Energy Simulations with Phase Change Materials for Very Hot-Humid Climates in Social Housing in Ecuador

Sustainability ◽

10.3390/su13031257 ◽

2021 ◽

Vol 13 (3) ◽

pp. 1257

Author(s):

Luis Godoy-Vaca ◽

E. Catalina Vallejo-Coral ◽

Javier Martínez-Gómez ◽

Marco Orozco ◽

Geovanna Villacreses

Keyword(s):

Thermal Comfort ◽

Phase Change ◽

Social Housing ◽

Energy Demand ◽

Phase Change Materials ◽

Thermal Sensation ◽

Electricity Consumption ◽

Different Types ◽

Climate Influences ◽

Energy Simulations

This work aims to estimate the expected hours of Predicted Medium Vote (PMV) thermal comfort in Ecuadorian social housing houses applying energy simulations with Phase Change Materials (PCMs) for very hot-humid climates. First, a novel methodology for characterizing three different types of social housing is presented based on a space-time analysis of the electricity consumption in a residential complex. Next, the increase in energy demand under climate influences is analyzed. Moreover, with the goal of enlarging the time of thermal comfort inside the houses, the most suitable PCM for them is determined. This paper includes both simulations and comparisons of thermal behavior by means of the PMV methodology of four types of PCMs selected. From the performed energy simulations, the results show that changing the deck and using RT25-RT30 in walls, it is possible to increase the duration of thermal comfort in at least one of the three analyzed houses. The applied PCM showed 46% of comfortable hours and a reduction of 937 h in which the thermal sensation varies from “very hot” to “hot”. Additionally, the usage time of air conditioning decreases, assuring the thermal comfort for the inhabitants during a higher number of hours per day.

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Experimental study of the influence of anticipated control on human thermal sensation and thermal comfort

Indoor Air ◽

10.1111/ina.12067 ◽

2013 ◽

Vol 24 (2) ◽

pp. 171-177 ◽

Cited By ~ 21

Author(s):

X. Zhou ◽

Q. Ouyang ◽

Y. Zhu ◽

C. Feng ◽

X. Zhang

Keyword(s):

Experimental Study ◽

Thermal Comfort ◽

Thermal Sensation

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Indoor Thermal Comfort Analysis: A Case Study of Modern and Traditional Buildings in Hot-Arid Climatic Region of Ethiopia

Urban Science ◽

10.3390/urbansci5030053 ◽

2021 ◽

Vol 5 (3) ◽

pp. 53

Author(s):

Haven Hailu ◽

Eshetu Gelan ◽

Yared Girma

Keyword(s):

Thermal Comfort ◽

Significant Role ◽

Indoor Environment ◽

Thermal Sensation ◽

Climatic Region ◽

Contributing Factors ◽

Objective Measurements ◽

Indoor Thermal Comfort ◽

Adaptive Comfort

Indoor thermal comfort is an essential aspect of sustainable architecture and it is critical in maintaining a safe indoor environment. Expectations, acceptability, and preferences of traditional and modern buildings are different in terms of thermal comfort. This study, therefore, attempts to evaluate the indoor thermal comforts of modern and traditional buildings and identify the contributing factors that impede or facilitate indoor thermal comfort in Semera city, Ethiopia. This study employed subjective and objective measurements. The subjective measurement is based on the ASHRAE seven-point thermal sensation scale. An adaptive comfort model was employed according to the ASHRAE standard to evaluate indoor thermal comfort. The results revealed that with regards to thermal sensational votes between −1 and +1, 88% of the respondents are satisfied with the indoor environment in traditional houses, while in modern houses this figure is 22%. Likewise, 83% of occupants in traditional houses expressed a preference for their homes to remain the same or be only slightly cooler or warmer. Traditional houses were, on average, in compliance with the 80% acceptability band of the adaptive comfort standard. The study investigated that traditional building techniques and materials, in combination with consideration of microclimate, were found to play a significant role in regulating the indoor environment.

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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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Comparative study on thermal comfort responses and sleep quality between Indonesian and Japanese students during summer in Japan

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/896/1/012074 ◽

2021 ◽

Vol 896 (1) ◽

pp. 012074

Author(s):

W Budiawan ◽

K Tsuzuki ◽

H Sakakibara

Keyword(s):

Relative Humidity ◽

Sleep Quality ◽

Comparative Study ◽

Thermal Comfort ◽

Thermal Sensation ◽

Temperate Climate ◽

Japanese Students ◽

The Mean

Abstract The comfort temperature and sleep quality of Indonesian residing in Japan during summer might be different from Japanese. As an extended previous research, this study aimed to compare the thermal comfort and sleep quality between Japanese and Indonesian students. Male Indonesian and Japanese students aged 20-35 years participated in this study. The participants completed a survey regarding thermal sensation before sleep. During sleep, actigraphy was used to monitor sleep. Additionally, the temperature and relative humidity of the participants’ bedrooms were recorded. The findings of this study indicated that Indonesian students’ bedroom temperature and relative humidity were not significantly different from those of Japanese students during the summer. Most of Indonesian students preferred neutral, like the Japanese students. According to a thermal comfort survey, Indonesians had the same sensation as Japanese (slightly comfortable). However, the Griffiths method revealed that the mean comfort temperature of Indonesian was higher than those of Japanese students. We also discovered that Indonesian students had shorter duration on bed and sleep minute than Japanese students. Furthermore, the sleep rate of Indonesian students was comparable to that of Japanese students. In conclusion, Indonesian students as tropical native became capable of adjusting to the hot and humid conditions in temperate climate, Japan.

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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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Experimental study of thermal comfort in a vehicle cabin during the summer season

E3S Web of Conferences ◽

10.1051/e3sconf/201911101048 ◽

2019 ◽

Vol 111 ◽

pp. 01048

Author(s):

Paul Danca ◽

Florin Bode ◽

Angel Dogeanu ◽

Cristiana Croitoru ◽

Mihnea Sandu ◽

...

Keyword(s):

Thermal Comfort ◽

Thermal Sensation ◽

Local Level ◽

Single Point ◽

Body Part ◽

Summer Season ◽

Thermal Manikin ◽

Vehicle Interior ◽

Mean Values ◽

Vehicle Cabin

Thermal comfort evaluation for vehicle occupants is very complicated due to the transient nature and non-uniformity of the vehicle interior. The thermal sensation of an automotive occupant is affected by the surrounding environment. More than this, the actual standard is proposing three evaluation indexes and was developed for steady state and controlled conditions and some of the indexes are not adapted for this complex environment. In this article the three standardized indexes values are compared in term of thermal comfort, in a vehicle passenger in summer season. The results are showing that the mean values of PMV/PPD model calculated in a single point with Comfort Sense equipment are far from the TSV mean values which was collected in questionnaires, while the teq index which was calculated with an advanced thermal manikin are closer to the TSV comfort votes. This may be explained by the fact that the TSV and teq consider the sensation for each body part at the local level. For a correct evaluation of the thermal comfort in non-uniform and transient environments like in the vehicles, is not enough to measure in a single point and the results to be considered in all the ambiance. The main conclusion is that the PMV/PPD indexes are not very well adapted to the vehicle environment.

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