scholarly journals A Comprehensive Thermal Comfort Analysis of the Cooling Effect of the Stand Fan Using Questionnaires and a Thermal Manikin

2019 ◽  
Vol 11 (18) ◽  
pp. 5091 ◽  
Author(s):  
Mun ◽  
Kwak ◽  
Kim ◽  
Huh
Keyword(s):  
Thermal Comfort ◽  
Energy Use ◽  
Thermal Sensation ◽  
Convective Heat Transfer Coefficient ◽  
Cooling Effect ◽  
Primary Data ◽  
Thermal Manikin ◽  
Air Conditioner ◽  
Data Set ◽  
Personal Cooling

In this study a quantitative analysis was performed on the effect on thermal comfort of the stand fan, a personal cooling device that creates local air currents. A total of 20 environmental conditions (indoor temperatures: 22, 24, 26, 28, and 30°C; fan modes: off, low (L) mode, medium (M) mode, and high (H) mode) were analyzed using questionnaires on male and female subjects in their 20s and a thermal manikin test. The contents of the questionnaire consisted of items on thermal sensation, thermal comfort, thermal acceptability, and demands on changes to the air velocity. This step was accompanied by the thermal manikin test to analyze the convective heat transfer coefficient and cooling effect quantitatively by replicating the stand fan. Given that this study provides data on the cooling effect of the stand fan in quantitative values, it allows for a comparison of energy use with other cooling systems such as the air conditioner, and may be used as a primary data set for analysis of energy conservation rates.

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

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.

scholarly journals Personal Atmosphere: Estimation of Air Conditioner Parameters for Personalizing Thermal Comfort

2020 ◽  
Vol 10 (22) ◽  
pp. 8067
Author(s):  
Tomohiro Mashita ◽  
Tetsuya Kanayama ◽  
Photchara Ratsamee
Keyword(s):  
Machine Learning ◽  
Thermal Comfort ◽  
Air Temperature ◽  
Fine Tuning ◽  
Air Conditioner ◽  
Data Set ◽  
Air Conditioning System ◽  
Air Conditioners ◽  
Uniform Distributions ◽  
Machine Learning Model

Air conditioners enable a comfortable environment for people in a variety of scenarios. However, in the case of a room with multiple people, the specific comfort for a particular person is highly dependent on their clothes, metabolism, preference, and so on, and the ideal conditions for each person in a room can conflict with each other. An ideal way to resolve these kinds of conflicts is an intelligent air conditioning system that can independently control air temperature and flow at different areas in a room and then produce thermal comfort for multiple users, which we define as the personal preference of air flow and temperature. In this paper, we propose Personal Atmosphere, a machine learning based method to obtain parameters of air conditioners which generate non-uniform distributions of air temperature and flow in a room. In this method, two dimensional air-temperature and -flow distributions in a room are used as input to a machine learning model. These inputs can be considered a summary of each user’s preference. Then the model outputs a parameter set for air conditioners in a given room. We utilized ResNet-50 as the model and generated a data set of air temperature and flow distributions using computational fluid dynamics (CFD) software. We then conducted evaluations with two rooms that have two and four air conditioners under the ceiling. We then confirmed that the estimated parameters of the air conditioners can generate air temperature and flow distributions close to those required in simulation. We also evaluated the performance of a ResNet-50 with fine tuning. This result shows that its learning time is significantly decreased, but performance is also decreased.

scholarly journals Thermal Mitigation of the Indoor and Outdoor Climate by Green Curtains in Japanese Condominiums

Climate ◽  
2020 ◽  
Vol 8 (1) ◽  
pp. 8
Author(s):  
Hiroto Abe ◽  
Hom B. Rijal ◽  
Ryoga Hiroki ◽  
Kentaro Iijima ◽  
Akira Ohta
Keyword(s):  
Thermal Comfort ◽  
Green Infrastructure ◽  
Energy Use ◽  
Air Conditioner ◽  
Outdoor Climate ◽  
Globe Temperature ◽  
Thermal Mitigation ◽  
Mitigation Methods ◽  
Reducing Energy ◽  
Indoor And Outdoor

In recent years, “green curtains” have become one of the most prevalent thermal mitigation methods in Japan. They can be considered as green infrastructure for achieving thermal comfort and reducing energy use. To examine the thermal mitigation effect of the green curtain for practical applicability in the condominium, the indoor and balcony temperatures for 48 days both in households with and without green curtains were analyzed. The balcony globe temperature of the households with green curtains was 0.6 °C lower than that of the households without green curtains, during air-conditioner usage. Furthermore, the air-conditioner usage time of the households with green curtains was 40% less than that of the households without green curtains. The results showed that green curtains are effective for achieving both thermal mitigation and energy saving in a condominium.

scholarly journals Thermal Comfort Condition in Affandi Museum Yogyakarta

2021 ◽  
Vol 2 (1) ◽  
pp. 20-27
Author(s):  
Azka Millatina ◽  
Nedyomukti Imam Syafii
Keyword(s):  
Thermal Comfort ◽  
Air Temperature ◽  
Architectural Design ◽  
Research Collaboration ◽  
Thermal Environment ◽  
Thermal Sensation ◽  
Primary Data ◽  
Humid Climate ◽  
Artificial Environment ◽  
Temperature Radiation

Thermal comfort is a basic human demand in interacting with space/architectural design. Determination of thermal comfort criteria can help the designer/architect in improving quality, function, and user thermal experience in an artificial environment. ISO 7730: 1994 standard states that the thermal sensation experienced by humans is the result of climate parameters (such as air temperature, radiation temperature, humidity, and wind speed) and human parameters (such as activity and clothing). These parameters were the focus of this study. The work program of this research collaboration was basically divided into 2 phases of activity, namely measuring and monitoring the conditions of thermal comfort in the Gallery 1 environment, Affandi Museum and providing recommendations for improvement of Gallery 1 thermal environment conditions. Primary data was taken from the indoor and outdoor measurement of air temperature, relative humidity and air velocity for 6 months. Physical architectural measurement of this study building and questionnaire methods followed the ASHRAE scale which was simplified to determine the level of thermal comfort, the scale of which was 2 (hot) to -2 (cold). The result of the measurement and analysis using a calculator based upon the ASHARE standard indicated that Gallery 1 of the Affandi Museum was in uncomfortable conditions. While the results of the questionnaire of 20 analyzes showed that at least 87,5% of respondents felt discomfort in Gallery 1, however, 60% of the respondent were still able to enjoy the collection and the atmosphere in gallery 1. The effective temperature index which provide 27,5-27,6 C and 66,7% RH as acceptable indoor environment in warm humid climate at Affandi museum case.

scholarly journals Thermal Perception in Mild Climate: Adaptive Thermal Models for Schools

2019 ◽  
Vol 11 (14) ◽  
pp. 3948 ◽  
Author(s):  
Miguel Ángel Campano ◽  
Samuel Domínguez-Amarillo ◽  
Jesica Fernández-Agüera ◽  
Juan José Sendra
Keyword(s):  
Thermal Comfort ◽  
Natural Ventilation ◽  
Energy Use ◽  
Thermal Environment ◽  
Thermal Sensation ◽  
Comfort Level ◽  
Thermal Perception ◽  
Accurate Design ◽  
Almost All ◽  
Autumn And Winter

A comprehensive assessment of indoor environmental conditions is performed on a representative sample of classrooms in schools across southern Spain (Mediterranean climate) to evaluate the thermal comfort level, thermal perception and preference, and the relationship with HVAC systems, with a comparison of seasons and personal clothing. Almost fifty classrooms were studied and around one thousand pool-surveys distributed among their occupants, aged 12 to 17. These measurements were performed during spring, autumn, and winter, considered the most representative periods of use for schools. A new proposed protocol has been developed for the collection and subsequent analysis of data, applying thermal comfort indicators and using the most frequent predictive models, rational (RTC) and adaptive (ATC), for comparison. Cooling is not provided in any of the rooms and natural ventilation is found in most of the spaces during midseasons. Despite the existence of a general heating service in almost all classrooms in the cold period, the use of mechanical ventilation is limited. Heating did not usually provide standard set-point temperatures. However, this did not lead to widespread complaints, as occupants perceive the thermal environment as neutral—varying greatly between users—and show a preference for slightly colder environments. Comparison of these thermal comfort votes and the thermal comfort indicators used showed a better fit of thermal preference over thermal sensation and more reliable results when using regional ATC indicators than the ASHRAE adaptive model. This highlights the significance of inhabitants’ actual thermal perception. These findings provide useful insight for a more accurate design of this type of building, as well as a suitable tool for the improvement of existing spaces, improving the conditions for both comfort and wellbeing in these spaces, as well as providing a better fit of energy use for actual comfort conditions.

scholarly journals A Field Study on Thermal Comfort in Multi-Storey Residential Buildings in the Karst Area of Guilin

2021 ◽  
Vol 13 (22) ◽  
pp. 12764
Author(s):  
Xinzhi Gong ◽  
Qinglin Meng ◽  
Yilei Yu
Keyword(s):  
Thermal Comfort ◽  
Energy Use ◽  
Thermal Environment ◽  
Thermal Sensation ◽  
Residential Buildings ◽  
Field Investigation ◽  
Karst Area ◽  
City Centre ◽  
Environment Design ◽  
Thermal Environments

It is important to consider reducing energy use while improving occupants’ indoor thermal comfort. The actual thermal comfort needs and demands should be considered to determine the indoor thermal environment design. In previous studies, research has not been carried out on thermal comfort in karst areas. Thus, a long-term field investigation was carried out on multi-storey residential buildings in the karst area of Guilin city centre during summer (from August 2019 to September 2019) and winter (from December 2019 to January 2020). In this study, the indoor thermal environments of three categories of dwellings were analysed. A total of 77 residential buildings with 144 households were randomly selected, and 223 occupants from 18 to 80 years old participated. A total of 414 effective questionnaires were collected from the subjects. The results show that there was an obvious conflict between the predicted mean vote (PMV) and the thermal sensation vote (TSV). The neutrality temperatures calculated by the regression method were 24.2 °C in summer and 16.2 °C in winter. The thermal comfort range was observed at operative temperatures of 20.9–27.5 °C in summer and 12.2–20.1 °C in winter. The desired thermal sensation for people in the Guilin karst area was not always reflected in the thermal neutrality range. A preference for warmness was identified in the survey.

scholarly journals Developing Guidelines for Thermal Comfort and Energy Saving during Hot Season of Multipurpose Senior Centers in Thailand

2019 ◽  
Vol 12 (1) ◽  
pp. 170
Author(s):  
Chorpech Panraluk ◽  
Atch Sreshthaputra
Keyword(s):  
Thermal Comfort ◽  
Natural Ventilation ◽  
Energy Use ◽  
Thermal Sensation ◽  
Air Velocity ◽  
Senior Centers ◽  
Air Conditioners ◽  
Chamber Study ◽  
Hot Season ◽  
Air Conditioning Systems

In Thailand, many government buildings and facilities are adapted to serve as Multipurpose Senior Centers (MSCs). However, most of them have been used without taking into account of thermal comfort of occupants. The present research aimed to develop guidelines for improving suitable indoor environment for the Thai elderly in hot season and analyze energy use of the 3 case-study MSCs. Both field study and climate-controlled chamber study were conducted. The obtained data were analyzed to develop the equation for predicting the thermal sensation, which would be inputted in the scSTREAM program for analysis purposes. The energy use was evaluated using the DOE-2 program. The results suggested that during 8:00 a.m.–12:00 p.m., natural ventilation should be used together with orbit fans to produce an actual air velocity of 0.64–0.73 m/s. From 12:00 p.m. to 4:00 p.m., air conditioners should set at 26.00–26.50 °C with an actual air velocity of 0.06–0.22 m/s. The results also showed that the developed guidelines could improve the level of thermal comfort from “slightly cool” to “neutral” and reduce energy use in hot season by 16.56% due to the reduction of cooling load and fan operation of air conditioning systems. Moreover, energy consumption in MSCs are also affected by the building parameters. These findings can be applied as guidelines for improving a large number of MSCs in Thailand.

scholarly journals Research on the effect of the size of the wall-hanging air-conditioner indoor unit on the indoor thermal comfort

2020 ◽  
Author(s):  
Kuanbing Caozhu ◽  
Changfa Ji
Keyword(s):  
Temperature Distribution ◽  
Thermal Comfort ◽  
Indoor Air ◽  
Thermal Sensation ◽  
Air Conditioner ◽  
Turbulent Model ◽  
Indoor Temperature ◽  
Indoor Thermal Comfort ◽  
Fluent Software ◽  
Indoor Comfort

Abstract The geometrical dimension of the wall-hanging air-conditioner indoor unit affects the indoor thermal comfort. In this paper, fluent software is used and standard k-e two equation turbulent model is chosen to carry out the simulation of the indoor temperature field and flow field of six different sizes of the single wall-hanging indoor air-conditioner in the room. The temperature distribution, velocity distribution and PMV distribution of the plane which is 1.8 m from the ground are given. It can be known that under the condition of six kinds of sizes of the wall-hanging air-conditioner indoor unit, when the size of the air-conditioner indoor unit is 0.4m × 0.2m × 0.2 m, the temperature variation at the z = 1.8 m section is relatively small, the temperature distribution is more uniform. When the size of the air-conditioner indoor unit is 0.5m × 0.2m × 0.2 m, the temperature difference at the z = 1.8 m section is relatively smaller, PMV is closest to 0, and the thermal sensation is almost moderate. Therefore when the size of the air-conditioner indoor unit is 0.5m × 0.2m × 0.2 m, better indoor comfort can be achieved.

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

1998 ◽  
Author(s):  
Margaret A. Kolka ◽  
Christina M. Kesick ◽  
Leslie Levine ◽  
Sharon A. McBride ◽  
Lou A. Stephenson
Keyword(s):  
Thermal Comfort ◽  
Thermal Sensation
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