Thermal Sensation of Thai Students in an Air Conditioned Space with a Pond Type Water Source and Air Velocity Step Change

With rapid urbanization, massive amount of energy is required to compensate the electricity usage thus calls for a need to Malaysian government issuing standard MS1525:2014 for temperature settings in office buildings to meet energy efficiency goal. In co-sharing spaces, personal thermal comfort is often not met due to the different thermal sensation at different location inside office rooms. This study was conducted at four postgraduate office spaces with cooling mode in university campus located at Kuala Lumpur to evaluate the occupant’s thermal sensation. We used different set-point temperature of air conditioning ranging from 18.0°C to 28.6°C. The indoor thermal variables such as air temperature, globe temperature, relative humidity, and air velocity are measured at each respondent’s workspace and 200 responses were recorded from ten subjects. The mean value of thermal sensations votes is -0.4 and were within comfort range. 76% of responses voted ‘neutral’ humidity sensation as occupants have adapted to humid condition in Malaysia. The comfort operative temperature found in this study is 24.9°C which indicates that the minimum recommended temperature for energy conservation did not deprive occupants from comfort.

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Reservoir-type water source vulnerability assessment: a case study of the Yuqiao Reservoir, China

Hydrological Sciences Journal ◽

10.1080/02626667.2014.1000917 ◽

2016 ◽

pp. 1-10 ◽

Cited By ~ 1

Author(s):

Ying Zhang ◽

Kai Zhang ◽

Zhiguang Niu

Keyword(s):

Vulnerability Assessment ◽

Water Source ◽

Yuqiao Reservoir ◽

Reservoir Type ◽

Type Water

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Thermal sensation under high-intensive exercise in naturally ventilated gymnasiums in hot-humid areas of China: Taking basketball players for example

Indoor and Built Environment ◽

10.1177/1420326x20978275 ◽

2020 ◽

pp. 1420326X2097827

Author(s):

Xiaodan Huang ◽

Qingyuan Zhang ◽

Zhangyuan Wang ◽

Xiaoli Ma

Keyword(s):

Evaluation System ◽

Thermal Sensation ◽

Systematic Evaluation ◽

Air Velocity ◽

Humid Climate ◽

Basketball Players ◽

Basketball Game ◽

Sport Activities ◽

Hot Humid Climate ◽

Radiant Temperature

As a public building for exercises and entertainments, gymnasiums play an important role in people's daily life. In regions with hot-humid climate, thermal sensation in gymnasiums is directly related to the human health as well as energy consumption. However, little can be found in the systematic evaluation system reported for thermal sensation of athletes in gymnasium in hot-humid climate regions; therefore, there is a need to develop a thermal sensation model for evaluating thermal sensation of athletes partaking sports in these environments. In this study, a field survey on thermal sensation of players in a basketball game was carried out in a naturally ventilated gymnasium in Guangzhou, China. The results showed that the human physiology and thermal sensation of subjects were highly different during active sport state. Moreover, the thermal sensation vote was increased with a rise in the air temperature, the mean radiant temperature and humidity ratio, while thermal sensation vote was reduced with an increase in the air velocity. The metabolic rate, systolic blood pressure and skin temperature were shown to have a positive correlation with the thermal sensation vote. According to the analysis, a predictive thermal sensation model, which has been developed by this study to estimate the thermal sensation under high-intensive sport activities in gymnasiums in regions with a high temperature and high humidity, was evaluated and validated.

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The effect of correlated colour temperature of lighting on thermal sensation and thermal comfort in a simulated indoor workplace

Indoor and Built Environment ◽

10.1177/1420326x16673214 ◽

2016 ◽

Vol 27 (3) ◽

pp. 308-316 ◽

Cited By ~ 8

Author(s):

Rupak R Baniya ◽

Eino Tetri ◽

Jukka Virtanen ◽

Liisa Halonen

Keyword(s):

Thermal Comfort ◽

Room Temperature ◽

Thermal Sensation ◽

Light Emitting Diode ◽

Air Velocity ◽

Light Emitting ◽

Colour Temperature ◽

Test Room ◽

Illuminance Level ◽

Colour Rendering

The ‘hue-heat’ hypothesis states that an environment which has wavelengths predominantly toward the red end of the visual spectrum feels ‘warm’ and one with wavelengths mainly toward the blue end feels ‘cool’. In order to test the hypothesis and to study the impacts of the correlated colour temperature of a light source on thermal sensation and thermal comfort, a study was conducted in a test room illuminated with an Light Emitting Diode (LED) lighting system with an adjustable correlated colour temperature where air temperature, air velocity, and relative humidity were kept constant. The correlated colour temperature of lighting inside the test room was changed gradually while keeping the colour rendering index values greater than 90, an illuminance level of 500 lx, and chromaticity difference (Duv) values within the limits of ±0.005. Sixteen study subjects were exposed to a ‘high room temperature’ (25℃) and a ‘low room temperature’ (20℃) on different days. The subjects were adapted to low correlated colour temperature (2700 K), medium correlated colour temperature (4000 K), and high correlated colour temperature (6200 K) lighting for 10 min and subsequently completed the questionnaire about their thermal comfort and thermal sensation. The results of this survey did not provide support for the hue-heat hypothesis and indicated that people felt thermally more comfortable in an indoor workplace at the correlated colour temperature of 4000 K than at the correlated colour temperature of 2700 K or 6200 K.

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A Data-Driven Thermal Sensation Model Based Predictive Controller for Indoor Thermal Comfort and Energy Optimization

Volume 2: Dynamic Modeling and Diagnostics in Biomedical Systems; Dynamics and Control of Wind Energy Systems; Vehicle Energy Management Optimization; Energy Storage, Optimization; Transportation and Grid Applications; Estimation and Identification Methods, Tracking, Detection, Alternative Propulsion Systems; Ground and Space Vehicle Dynamics; Intelligent Transportation Systems and Control; Energy Harvesting; Modeling and Control for Thermo-Fluid Applications, IC Engines, Manufacturing ◽

10.1115/dscc2014-6131 ◽

2014 ◽

Author(s):

Xiao Chen ◽

Qian Wang

Keyword(s):

Thermal Comfort ◽

Thermal Sensation ◽

Energy Optimization ◽

Data Driven ◽

Air Velocity ◽

Comfort Index ◽

Indoor Thermal Comfort ◽

Occupant Feedback ◽

Predictive Controller ◽

Radiant Temperature

This paper proposes a model predictive controller (MPC) using a data-driven thermal sensation model for indoor thermal comfort and energy optimization. The uniqueness of this empirical thermal sensation model lies in that it uses feedback from occupants (occupant actual votes) to improve the accuracy of model prediction. We evaluated the performance of our controller by comparing it with other MPC controllers developed using the Predicted Mean Vote (PMV) model as thermal comfort index. The simulation results demonstrate that in general our controller achieves a comparable level of energy consumption and comfort while eases the computation demand posed by using the PMV model in the MPC formulation. It is also worth pointing out that since we assume that our controller receives occupant feedback (votes) on thermal comfort, we do not need to monitor the parameters such as relative humidity, air velocity, mean radiant temperature and occupant clothing level changes which are necessary in the computation of PMV index. Furthermore simulations show that in cases where occupants’ actual sensation votes might deviate from the PMV predictions (i.e., a bias associated with PMV), our controller has the potential to outperform the PMV based MPC controller by providing a better indoor thermal comfort.

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Thermal comfort in the low energy building - validation and modification of the Fanger model

E3S Web of Conferences ◽

10.1051/e3sconf/202124615003 ◽

2021 ◽

Vol 246 ◽

pp. 15003

Author(s):

Natalia Krawczyk

Keyword(s):

Thermal Comfort ◽

Indoor Air ◽

Thermal Sensation ◽

Carbon Dioxide Concentration ◽

Low Energy ◽

Air Velocity ◽

University Of Technology ◽

Calculation Results ◽

Thermal Comfort Model ◽

The Impact

Nowadays, we spend most of our time inside buildings. Thus, ensuring adequate thermal comfort is an important issue. The paper discusses the issue of thermal comfort assessment in the intelligent low energy building “Energis” of Kielce University of Technology (Poland). The tests conducted in a selected lecture theater focused on collecting anonymous questionnaires containing thermal sensation and air quality votes of the respondents as well as performing measurements of indoor air parameters (air and globe temperatures, relative humidity, air velocity and CO2 concentration). Based on the obtained data a comparison has been done between the actual sensation votes of the volunteers and the calculation results performed with the Fanger thermal comfort model. Two indices have been considered in the paper: PMV (Predicted Mean Vote) and PPD (Predicted Percentage Dissatisfied). A modification of the model has also been proposed, which considers the impact of the carbon dioxide concentration on thermal comfort.

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Thermal comfort, thermal sensation and skin temperature measurements using demand-controlled ventilation for individual cooling

E3S Web of Conferences ◽

10.1051/e3sconf/202017206001 ◽

2020 ◽

Vol 172 ◽

pp. 06001

Author(s):

Håkon Solberg ◽

Kari Thunshelle ◽

Peter Schild

Keyword(s):

Thermal Comfort ◽

Skin Temperature ◽

Energy Demand ◽

Thermal Sensation ◽

Air Velocity ◽

Climate Chamber ◽

Biometric Data ◽

Ongoing Research ◽

Demand Controlled Ventilation ◽

The Relationship

An increasing part of modern building's energy demand is due to cooling. An ongoing research project investigates the possibility to reduce the energy consumption from cooling by utilizing an individually controlled active ventilation diffuser mounted in the ceiling. This study looks at thermal sensation and thermal comfort for 21 test persons exposed to an innovative user controlled active ventilation valve, in a steady and thermally uniform climate chamber. Furthermore, the relationship between biometric data from the test persons skin temperature and sweat, and the test persons thermal sensation scores has been investigated. Each test person was exposed to three different room temperatures in the climate chamber, 24°C, 26°C and 28°C respectively, to simulate typical hot summer conditions in an office in Norway. At a room temperature of 26°C it was possible to achieve acceptable thermal comfort for most test persons with this solution, but higher air velocity than 0.75 m/s around the test persons bodies at room temperatures of 28°C is required to ensure satisfactory thermal comfort.

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A Fan in Winter

Proceedings of the Human Factors Society Annual Meeting ◽

10.1177/154193128302700821 ◽

1983 ◽

Vol 27 (8) ◽

pp. 742-745 ◽

Cited By ~ 1

Author(s):

Frederick H. Rohles ◽

Byron W. Jones

Keyword(s):

Thermal Comfort ◽

Thermal Sensation ◽

Test Chamber ◽

Air Velocity ◽

Subjective Responses ◽

Human Thermal Comfort ◽

Significant Difference ◽

Maximum Period ◽

Air Space ◽

Indoor Conditions

In order to determine the effect of ceiling fans on human thermal comfort under winter indoor conditions, 72 subjects (36 men and 36 women) were exposed to 21°C/40% rh for 3 hours while experiencing still air conditions (0.08 m/s) and air velocities where a ceiling fan was operating in a upward-thrust mode at 2 velocities (0.18 and 0.28 m/s). Two subjective responses, thermal sensation and thermal comfort, were recorded each half hour. The results showed that after 2 hours, which may be assumed to be the maximum period of time that an individual would sit without getting up, the subjects recorded (1) the same neutral thermal sensation when the fan was at the still air condition (0.0 8 m/s) as when it was producing an air velocity of 0.18 m/s, (2) a slightly cool thermal sensation at a velocity of 0.28 m/s and (3) no significant difference in thermal comfort between still air (0.08 m/s) and velocities up to 0.28 m/s. It was concluded that the air movement created by operating the ceiling fan under winter conditions does not contribute to nor detract from human comfort nor did it produce any response resembling wind chill. These results were considered conservative since no temperature stratification existed in the test chamber air space which would be expected in exist in a conventionally heated room space.

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Cooling with Box Fans

Proceedings of the Human Factors Society Annual Meeting ◽

10.1177/154193128202600204 ◽

1982 ◽

Vol 26 (2) ◽

pp. 123-127

Author(s):

Eric Rosen ◽

Stephan Konz

Keyword(s):

Thermal Comfort ◽

Room Temperature ◽

Thermal Sensation ◽

Office Work ◽

Air Velocity ◽

Preferred Direction ◽

The Subject ◽

Paper And Pencil ◽

C 78

Two experiments are described. Experiment 1 investigated the preferred direction of air upon a person. Forty males sat in front of a box fan in 12 different seating orientations (30° increments). Air velocity was .7 m/s (140 ft/min); room temperature was 28 C (82 F) with 40% rh. The preference was bimodal with the most preferred directions from the front or the rear; velocities from the side were less preferred. Experiment 2 investigated 3 velocities (“still air”, .8 m/s (160 ft/min) and 1.3 m/s (260 ft/min)) at 3 temperatures (25.6, 27.8 and 30 C; 78, 82, 86 F). Eight subjects each spent three hours in each of the 9 conditions. Clothing was standardized at about .5 clo. Subjects did a paper and pencil task (maze) and a peg into hole task. Thermal comfort and thermal sensation ballots were completed every 15 min. At the end of 150 min., they moved their chair in relation to the fan so as to select their preferred velocity. The current recommended ceiling of .8 m/s for sedentary office work is too low as the subject-selected velocity was .7 m/s at 25.6 C, was 1.0 m/s at 27.8 C and was 1.2 m/s at 30 C. These results were confirmed by the thermal comfort and thermal sensation ballots. Depending on the criterion used, for seated sedentary work in warm conditions, every 0.1 m/s (20 ft/min) increase in air velocity offsets approximately a 0.4 C (0.7 F) increase in temperature (0.7 < V < 1.2 m/s).

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