• 한국자동차공학회논문집
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• 제20권5호
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• pp.120-129
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• 2012

As the recent advancement of automobile industry, there has been a great interest in the thermal comfort of the passengers inside the cabin of an automobile. Thermal comfort is affected by temperature, velocities, and mean radiation temperature of air, thermal resistance of clothes and physical active level of human. The present study performed computational analysis to select the location of air-conditioning vent that improves thermal comfort inside the cabin. In order to do this, we considered various air vent positions, and thermal flow analysis of each case is performed using CFD for the cabin with four passengers. The thermal comfort is evaluated using the computational results and the optimum location of air vent is suggested.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.1180-1185
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• 2006

Modern people spend most of time at indoor space, such as office or classroom. Especially, occupants are exposed to the airtight indoor air quality (IAQ) for a long time, At present, many studies on the air-conditioning systems are more focused on the individual thermal comfort than the thermal efficiency due to increase of the concern of health. There are several factors which are influenced thermal comfort, such as temperature, humidity, convection and air movement, etc. Also, the individual factor, such as age, gender, Physical constitution and habit, should be considered. The 4-way cassette type air conditioner is known to bring out better performance about thermal comfort than the traditional one. This study is performed on the higher ceiling environment than the common buildings or classrooms. Also, this study analyzed on the Indoor thermal comfort by diffusing direction of 4-way cassette air conditioner with various discharge angles, $45^{\circ},\;50^{\circ},\;55^{\circ}$ and $60^{\circ}$. Using a commercial code, FLUENT, three-dimensional transient air thermal flow fields are calculated with appropriate wall boundary conditions and standard $k-{\epsilon}$ turbulence model. Results of velocity and temperature distributions are graphically depicted with various discharge angles.

• Architectural research
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• 제25권4호
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• pp.73-84
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• 2023

Indoor thermal conditions greatly affect the health and comfort of humans who occupy the space in it. The purpose of this research is to analyze the influence of water and vegetation elements as a microclimate modifier in buildings to obtain thermal comfort through the study of thermal environment models. This research covers two objects, namely public buildings and housing in Makassar City, South Sulawesi Prov-ince - Indonesia. Quantitative methods through field surveys and measurements based on thermal and personal variables. Data analysis based on ASHRAE 55 2020 standard. The data was processed with a parametric statistical approach and then simulated with the Computational Fluid Dynamics (CFD) simulation method to find a thermal prediction model. The model was made by increasing the ventilation area by 2.0 m2, adding 10% vegetation with shade plant characteristics, moving water features in the form of fountains and increasing the pool area by 15% to obtain PMV + 0.23, PPD + 8%, TSV-1 - +0, Ta_25.7℃, and relative humidity 63.5 - 66%. The evaluation shows that the operating temperature can analyze the visitor's comfort temperature range of >80% and comply with the ASHRAE 55-2020 standard. It is concluded that water elements and indoor vegetation can be microclimate modifiers in buildings to create desired comfort conditions and adaptive con-trols in buildings such as the arrangement of water elements and vegetation and ventilation systems to provide passive cooling effects in buildings.

• KIEAE Journal
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• 제10권4호
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• pp.67-73
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• 2010

As more and more people desire to live in an apartment complex with a comfortable outdoor space, many construction company became interested in outdoor design. In order to increase the use of outdoor space and create the most pleasant environment, outdoor thermal environment and comfort should be evaluated quantitatively from the design stage. This study utilized ENVI-met 3.1 model to analyze outdoor thermal environment in apartment complex, and evaluated outdoor thermal comfort in 6 points of apartment complex. The physiologically equivalent temperature(PET) was employed as a outdoor thermal index. Playground B had a poor thermal environment with the maximum PET $43^{\circ}C$ (Very hot). Because shading by building and tree didn't affect outdoor thermal environment of playground B. To design comfortable outdoor space from the view point of thermal environment, the factors influencing Mean radiant temperature(MRT) and wind speed should be considered in design stage. Since it is difficult to control outdoor thermal environment compared with indoor environment, we should take into account an assessment for outdoor thermal environment and comfort in outdoor design stage.

• 한국환경과학회지
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• 제14권2호
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• pp.215-220
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• 2005

Thermal neutrality is not enough to achieve thermal comfort. The temperature level can be the optimal, and still people may complain. This situation is often explained by the problem of local discomfort. Local discomfort can be caused by radiant asymmetry, local air velocities, too warm and too cold floor temperature and vertical temperature difference. This temperature difference may generate thermal discomfort due to different thermal sensation in different body parts. Therefore, thermal comfort can not be correctly evaluated without considering these differences. This study investigates thermal discomfort sensations of different body parts and its effect on overall thermal sensation and comfort in air-heating room. Experimental results of evaluating thermal discomfort at different body parts in an air-heating room showed that thermal sensation on the shoulder was significantly related to the overall thermal sensation and discomfort. Although it is known that cool-head, warm-foot condition is good for comfort living, cool temperature around the head generated discomfort.

• 한국주거학회논문집
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• 제17권3호
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• pp.1-7
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• 2006

The aim of the research was to evaluate the characteristics of thermal environment and thermal comfort in the Dry Double floors Hydronic Ondol System. Physical indoor thermal environments (the floor surface temperature, the vertical temperature, etc.) and skin temperature have especially been measured. Physical features conditions, sensation, thermal comfort, humidity sensation, comfort of body were investigated for the survey. As a result, (1) During the operation of the boiler (12 hour), the average indoor temperature is appeared to be $21.6^{\circ}C$. The floor surface temperature showed peak value of $31.4{\sim}40.6^{\circ}C$ after 8hours 30minutes after the start-point of the heating. The vertical difference of temperature was turned out to be not uniform. (2) While the skin temperature showed a narrow distribution of temperature in the Dry Double floors Hydronic Ondol system. (3) The response to thermal comfort which people felt was satisfactory, and most of them felt dry during the test.

• 감성과학
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• 제6권1호
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• pp.33-37
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• 2003

인간 감성변화의 기본인 피부온도 및 피복내 온습도 측정을 위한 시스템과 감성공학적 해석을 위한 보다 정밀하고 안정성이 있는 센서의 응답성 및 회로의 선형화에 대한 연구를 수행하고, 의복내 환경평가 및 실내 온습도 측정등의 다양한 감성공학적 해석을 위한 소프트웨어의 개발이 본 연구의 목적이다. 본 연구에는 손쉬운 온습도 변환장치와 풍부한 저장능력 등 다양한 분야에서 활용이 가능한 온습도 측정기와 이에 필요한 센서를 개발하고 측정기의 선형화특성을 평가하였다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.970-975
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• 2008

This study considers indoor thermal comfort in an ondol space by supply vent configurations to prevent cold draft in winter. A specially-designed vent cap has been investigated in comparison with a round pan-type vent and a simple opening without a cap. Numerical simulations have been conducted using CFD to analyze thermal comfort indices such as Predicted Mean Vote (PMV) and Effective Draft Temperature (EDT) as well as air distribution index i.e. Air Diffusion Performance Index (ADPI). Results show the new vent cap provides improved thermal comfort conditions especially near ondol heated floor, as the cold outdoor air spreads upwards along the vertical wall before reaching occupant region near floor. This paper includes discussions on the flow and comfort distributions created by the thermal jets from the vents.

• 한국자동차공학회논문집
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• 제24권1호
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• pp.82-89
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• 2016

This paper presents computational fluid dynamics (CFD) analysis on passenger thermal comfort in a train. Human thermal comfort in vehicles depends mainly on air temperature, mean radiant temperature, air velocity, humidity, and direct solar flux, as well as the level of activity and thermal properties of clothing and seat. The velocity and temperature distribution in a train with and without passengers are reported. The thermal comfort in a passenger train are also presented based on PMV and PPD indices with 16 segments of the human body.

• 수산해양교육연구
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• 제18권2호
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• pp.77-84
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• 2006

This research evaluates thermal comfort by comparing the case of maintain cooing temperature of room with the case of raising it at the point of time that human body begins to adapt. An experiment uses constant temperature & humidity chamber 2 places. Pretesting room make up summer season environment, the testing room control by air-conditioner. In condition that maintain temperature of $33^{\circ}C$. The subjects stay in the pretesting room during the 30 minute for the heat storage amount of the normal summertime. The subjects stay in the testing room under each case (case 1: maintaining $24^{\circ}C$, case 2: maintaining $26^{\circ}C$, case 3: up $1^{\circ}C$ after maintaining $24^{\circ}C$ during 30 minute, case 4: up $1^{\circ}C$ after maintaining $26^{\circ}C$ during 40 minute). 1. Result of comparison of case 1 and case 2 appears that thermal sensitive vote examine from slight cool to cool and thermal comfort examine slight comfort by temperature rise at human body adaptation point of time.2. Test of case 3 and case 4 appear similar value at thermal sensitive vote and thermal comfort.3. Through the case 2 and case 4, continuous thermal comfort maintain at $24^{\circ}C$, if raise $26^{\circ}C$, same thermal comfort maintain after a human body adaptation temperature rising effect bring energy saving.