• Title/Summary/Keyword: Thermal Comfort Temperature

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The Study for Evaluation of Thermal Comfort in Passenger Cabin on Cruise Ship (크루즈선 객실의 공조 쾌적성 평가에 관한 연구)

  • Koo, Keun-Hae;Lee, Ho-Ki;Choi, Jae-Woong;Lee, Jae-Keun
    • Journal of the Society of Naval Architects of Korea
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    • v.48 no.1
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    • pp.62-66
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    • 2011
  • The present work focuses on the evaluation of thermal comfort in passenger cabin of a cruise ship. A computational fluid dynamics (CFD(Airpak)) is used to calculate air velocity and temperature distribution in the passenger cabin as well as PMV and PPD. The CFD is used to simulate two different cases, room unit system and wardrobe duct system. Both of cases are simulated in summer environment condition. The room unit system and wardrobe duct system are compared and evaluated by ISO 7730 thermal comfort categories. The performance of room unit system is shown to be more effective for this typical case of passenger cabin.

The Study on Efficiency Improvement of Thermal Storage Tank for Solar Combined Heating System (태양열 난방 일체형 복합시스템의 축열조 효율개선에 관한 연구)

  • Lyu, Nam-Jin;Ko, Kwang-Soo;Han, Yu-Ri;Park, Youn-Cheol
    • 한국신재생에너지학회:학술대회논문집
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    • 2006.11a
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    • pp.188-192
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    • 2006
  • This study is conducted to improve efficiency of thermal storage tank. The thermal storage tank was designed to store heat energy that obtained from solar or the others heat sources. However, it has difficulties in storing heat with uniform temperature through the entire tank with respect to vertical direction. This kind of maldistribution of the supplied heat to the storage tank effects on the system performance. In this study is focused on utilization of the thermal stratification to improve thermal comfort for people in the house. To enhance temperature stratification of the tank, a distributor was designed and Installed in the middle of the tank. The distributor is supplies hottest water to the top side of the tank which is very close to inlet of the supply line to the heating load. The hottest water that is accumulated on top side of the tank is firstly supplied to the load with higher temperature. Reminder water takes a little time to warming up until desired supply temperature reached. This kind alternating selection of the supply temperature is improve thermal comfort with moderated system performance.

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A Study on the Establishment of the Optimal Temperature Limits for Man's Thermal Comfort in an Asymmetric Radiant Space (불균등 복사공간의 쾌적온도범위 설정에 관한 연구)

  • Sohn, Jang-Yeul;Kong, Sung-Hoon;Yun, Yong-Jin
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.14 no.3
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    • pp.187-199
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    • 1985
  • The low-temperatured radiant heating System like a panel heating system is recognized as nice means to make comfortable indoor environment. Perhaps, 'Ondol' would be a typical example of the Panel heating system. Nevertheless. Occupants in a radiantly heated Space which has an asymmetric radiant field may feel thermally discomfort due to the asymmetric radiation. The aim of this Study is to suggest the fundamental technical data for establishing Standards of thermally comfortable environment when designing a radiant heating System. Thermal distribution of indoor environment and the skin temperature of the occupants were measured at experimental room in KIER (Korea Institute of Energy and Resources). Whole/Regional thermal and comfort Sensation votes of the occupants were taken simultaneously in order to investigate the relationships between thermal environmental factor and the occupants' responses. The effect of an asymmetric radiation on thermal environment and the occupants' responses was analyzed by using a v.r.t.(vector radiant temperature). By this means, the thermally neutral limits for the ambient air temperature and the floor surface temperature by the occupants' responses were Obtained. And the recommended temperature limits of the indoor surface were derived from the experimental work and the theory of radiant and will provide thermal neutrality for man without any discomfort on the part of the body.

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Thermal Comfort of the Sports/Leisure Clothing with the Heat Storage/Reflection Function - Wearing Evaluation under the Condition of 0x00B1;1℃ and 50±5% RH - (축열/체열반사기능을 가진 스포츠 레저복의 온열쾌적성 - 0±1℃, 50±5% RH 환경에서의 착의평가 -)

  • Kim, Tae-Gyou;Song, Min Kyu;Lee, Chang Min;Kwon, Oh Kyung
    • Fashion & Textile Research Journal
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    • v.20 no.4
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    • pp.474-481
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    • 2018
  • For this study, we developed clothing in which textile materials that were excellent weather control function for the cold environment and we performed the human subject test with developed clothing to determine the thermal comfort. We used 2 clothing samples developed (A and B, hollow yarn+moisture absorption/quick drying yarn, 3 layers, high stretchable, heat reflection film and lamination treated) and a control sample (Ctrl.) for the human subject test and 8 adult males were used as a human subjects and environmental conditions of chamber were $0{\pm}1^{\circ}C$. $50{\pm}5%RH$, 0.3m/sec. The results were as follows: The average skin temperature and hand, thigh temperature of B were higher than B and Ctrl. (p<.05). The micro-climates of B were near to thermal comfort range which is $32{\pm}1^{\circ}C$ and $50{\pm}10%\;RH$. The chest temperature of B was significantly higher than others (p<.05). The relative humidity of B was lower than others and kept stable rather than others. The thermal sensation of B was near the "neutral" and was significantly different from Ctrl. (p<.01) and the weight loss of B was lower than Ctrl. (p<.05). The counting task and hand temperature was positively related and the counting task value of B and A is bigger than Ctrl. and that of A was bigger than Ctrl. (p<.05).

An Analytical Study on Indoor Thermal Comfort Performance According to the Automatic Control of Internal-External Blind

  • Lee, Do-Hyung;Kim, Tae-Woo;Yoon, Jong-Ho
    • KIEAE Journal
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    • v.14 no.3
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    • pp.31-38
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    • 2014
  • The purpose of this study is to analyse PMV (Predicted Mean Vote) and PPD (Predicted Percentage of dissatisfied) by automatic control of slat-type vertical blind. EnergyPlus, a building energy analysis software has been used for this study. The energy model is calibrated in Energy Plus using measured zone temperature and glass surface temperature data for one day and thermal comfort performance inside the building analysis was carried out. The calibrated data has the MBE of 4% and Cv(RMSE) of 10%. The result was that, for better zone thermal comfort, installation of blind on the outside is more appropriate than inside or no blind case. Additionally, different glazing types were compared and it was found that Triple Low-e glass is the most favorable.

Thermal Comfort Aspects of Pesticide-protective Clothing Made with Nonwoven Fabrics

  • Choi Jong-Myoung;Tanabe Shin-Ichi
    • International Journal of Human Ecology
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    • v.3 no.1
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    • pp.55-72
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    • 2002
  • The purpose of this study was to evaluate the thermal resistance of pesticideprotective clothing and to investigate its subjective wear performance. Three different nonwoven fabrics, which provide barrier properties against water and pesticide, were used to manufacture the experimental clothing: spunbonded nonwoven (SB), spunbonded/meltblown/spunbonded nonwoven (SM), and spunlaced nonwoven (SL). The thermal insulation values of the experimental clothing were measured with a thermal manikin, and other wear trials were performed on human subjects in a climate chamber at $28^{\circ}C$, with 70% R.H. and air movement at less than 0.15m/s. Our results found that the thermal resistance was lower in the SB experimental clothing than in the others; that the mean skin temperature of subjects who wore the experimental clothing made with SL was significantly lower than that of subjects who wore the SB and SM clothing; and that the microclimate temperature and humidity with SB were significantly higher than that of the others. Overall, the experimental clothing made with SL was more comfortable than the others in terms of subjective wear sensations.

A Study on the Characteristics of Perceived Temperature over the Korean Peninsula During 2007 Summer (한반도 2007년 여름철 인지온도 특성 연구)

  • Byon, Jae-Young;Kim, Jeong-Sik;Kim, Ji-Young;Choi, Byoung-Cheol;Choi, Young-Jean;Graetz, Angelika
    • Atmosphere
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    • v.18 no.2
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    • pp.137-146
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    • 2008
  • This study examines one thermal index, perceived temperature (PT), over the Korean Peninsula during 2007 summer. Heat/cold stress has been described using air temperature and humidity for warm seasons and air temperature and wind velocity in the cold conditions, while PT is based on a heat budget model of the human body that considers air temperature, humidity, wind velocity and radiation effect regardless of climates, regions and seasons. PT is higher about $4-5^{\circ}C$ than air temperature in the summer. Humidity increases PT, while wind tends to reduces PT possibly by evaporation of water vapor. The geographical distribution of summer PT indicates that the lowest PT happened in the east central region, with the appearance of the highest PT in the inland of southern region in Korea. Although the latitudinal trend shows that PT decreases northward, inland PT is higher than that of coastal region. Compared to the heat index or the discomfort index that considers air temperature and humidity, PT represents distinctive regional characteristics of thermal comfort. The distribution of PT shows that it may be a useful thermal index for the assessment of thermal comfort or stress region in the Korean Peninsula.

A Numerical Study of Automotive Indoor Thermal Comfort Model According to Boarding Conditions and Parameters Related to HVAC (HVAC 관련 매개변수 및 탑승조건에 따른 자동차 실내의 온열쾌적성 평가모델에 관한 수치해석적 연구)

  • Yoon, Seong Hyun;Park, Jun Yong;Son, Deok Young;Choi, Yunho;Park, Kyungseok
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.38 no.9
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    • pp.979-988
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    • 2014
  • Recently, the interest in the thermal comfort is ever increasing as the time people stay in the automobile is gradually increasing. So far, however, the cooling performance of the HVAC(heating and ventilation air conditioning) system is evaluated by thermal environment criteria such as indoor air velocity and temperature, not by a thermal comfort index. Furthermore, the precise criteria has not been established yet when the thermal comfort for the automobile is evaluated using numerical analysis. In this study, the numerical analysis of automobile indoor thermal comfort according to various parameters such as HVAC operating mode, airflow, passenger boarding conditions is performed during the HVAC system's initial operating time(20 minutes). The solar ray tracing model and S2S radiation model are used and validated to simulate an external heat source. Based on this study, an evaluation model which can predict the thermal comfort index for the combination of the above parameters is presented.

Evaluation of the Functional and Non-functional Seat Sponge Effect in Sitting Chairs

  • Min, Seung Nam;Park, Se Jin;Subramaniyam, Murali;Lee, Heeran
    • Journal of the Ergonomics Society of Korea
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    • v.33 no.4
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    • pp.255-265
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    • 2014
  • Objective: The purpose of this study was to evaluate comfort levels of functional and non-functional chairs using subjective comfort rating, interface pressure measurement, muscle activity measurement, and skin temperature measurement. Background: Chairs are used for a prolonged period of time for sitting in many places such as the office, at university, at school, in industry, and so on. Almost all people use chairs in their everyday life. The functional properties of the chair are associated with comfort. Method: The subjective evaluation contains questions regarding chair comfort which can be rated with five point scale. The body-seat interface pressure was measured using a pressure mat system. The symmetry of sitting was measured using electromyography. The change in body part (thigh and buttock) temperature before and after sitting on a chair was measured with an infrared camera. Results: Participants rated significantly (p < 0.05) higher comfort scores for the functional chair in relation to the buttock and thigh region. Also, the participants felt a better cushion effect in the functional chair. When using the functional chair, lower interface pressure, better thermal comfort, and better symmetry of erector spinae muscle activity were observed. Conclusion: Overall, interface pressure measurement, muscle activity measurement, thermal imaging and subjective comfort score results showed that the functional chair was more comfortable than the non-functional chair. Application: The adopted methodologies could be used to measure the seating comfort of train seats.

The Study for Evaluation of thermal comfort in office on offshore (해양플랜트 사무공간의 공조 쾌적성 평가에 관한 연구)

  • Lim, Hongseok;Kim, Panjung
    • Special Issue of the Society of Naval Architects of Korea
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    • 2017.10a
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    • pp.67-72
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    • 2017
  • This paper presents on the evaluation of thermal comfort in office on offshore. In living quarter of offshore, strict air conditioning performance is required to office on offshore and displacement ventilation is applied to office space which rooms are required to confirm the thermal environment. The computational fluid dynamics (CFD) is performed to calculate the temperature, air velocity in office and thermal comfort such as PPM & PPD is evaluated by the CFD result.

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