• 제목/요약/키워드: Thermal Condition

검색결과 3,159건 처리시간 0.029초

쾌적한 의복기후를 위한 피복구성에 관한 연구 ( I ) -착의양과 한서감각을 중심으로- (A Study on the Clothing Composition to the Comfortable Clothing Climate; Clothing Weights and Thermal Sensation( I ))

  • 박우미;이순원
    • 한국의류학회지
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    • 제7권1호
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    • pp.37-43
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    • 1983
  • The objective of the study is to obtain the basic data to establish the standard value of proper clothing weights in the change of thermal environment. For the purpose of this research, clothing weight and thermal sensation have been collected from 160 college student in Seoul and Kwangju area in April, July, October. Results are as follows : 1. Subjects were in Comfortable condition, particularly in Spring and Autumn. But in summer they were in warm condition and the case were reversed in winter when they were under cool condition. 2. The frequency of comfortable thermal sensation were low below 16.5 degree, above 27.5 degree, and were high between 16.5 degree and 23 degree on room temperature. 3. Generally, the positive correlation were found between clothing weights and thermal sensation. 4. Clothing weights and thermal comfort were as follows. Season : Spring, Autumn, Room Temperature(${\circ}C$) : 16.3$\~$23, Clothing Weights($g/m^2$) : 589.9$\~$750.6, Season : Summer Room Temperature(${\circ}C$) : 27$\~$32, Clothing Weights($g/m^2$) : 362.4$\~$432.5, Season : Winter, Room Temperature(${\circ}C$) : 12.5$\~$19.3, Clothing Weights($g/m^2$) : 913.7$\~$1206.2

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사용후핵연료 저장용기의 정상 및 비정상조건에 대한 열해석 (Thermal Analysis of a Spent Fuel Storage Cask under Normal and Off-Normal Conditions)

  • Ju-Chan Lee;Kyung-Sik Bang;Ki-Seog Seo;Ho-Dong Kim;Byung-Il Choi;Heung-Young Lee
    • 방사성폐기물학회지
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    • 제2권1호
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    • pp.13-22
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    • 2004
  • This study presents the thermal analyses of a spent fuel dry storage cask under normal and off-normal conditions. The environmental temperature is assumed to be 15 $^{\circ}C$ under the normal condition. The off-normal condition has an environmental temperature of 38 $^{\circ}C$. An additional off-normal condition is considered as a partial blockage of the air inlet ducts. Two of the four air inlet ducts are assumed to be completely blocked. The significant thermal design feature of the storage cask is the air flow path used to remove the decay heat from the spent fuel. Natural circulation of the air inside the cask allows the concrete and fuel cladding temperatures to be maintained below the allowable values. The finite volume computational fluid dynamics code FLUENT was used for the thermal analysis. The maximum temperatures of the fuel rod and concrete overpack were lower than the allowable values under the normal and off-normal conditions.

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한국 남성용 단일의복의 앙상블 조합시의 온열특성 변화에 관한 연구 - 무풍, 풍속환경하에서 - (A Study on Changes in Thermal Performances in Ensembles Made up of Single Garments Marketed for Korean Men - In Still and Dynamic Air Conditions -)

  • 송민규;권서윤;정현미
    • 한국의류산업학회지
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    • 제14권4호
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    • pp.660-668
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    • 2012
  • The purpose of this study is to analyze the thermal characteristics of garments marketed for Korean males and to investigate the influence of each garment on ensemble, by measuring their insulation values(clo) using thermal manikins. The results are as follows. The total insulations(clo) of ensembles for S/S seasons are between 1.46 and 2.6 clo, with the mean of 2.12 clo. The insulation in the still air condition is 1.23 clo, which means a decrease of 42% compared to the total insulation of all the component garments. The insulation of ensembles for S/S seasons in the dynamic air condition decreased by 46.8%, compared to the still air condition. The total insulation(clo) of ensembles for F/W seasons is between 3.84 and 7.36 clo with the mean of 4.74 clo. The insulation in the still air condition is 2.26 clo, which means a decrease of 53.6% compared to the total insulation of all the component garments. The insulation of ensembles for F/W seasons in the dynamic air condition decreased by 36.2%, compared to the still air condition. As the clo value of each component garment gets higher, the insulation of ensembles gets higher. Especially, the insulation of ensembles was more influenced by outer wear than inner wear. The insulation of ensembles could be predicted by the insulation of outerwear better.

콘크리트의 열전도율에 관한 실험적 연구 (Experimental Study on Thermal Conductivity of Concrete)

  • 김국한;전상은;방기성;김진근
    • 콘크리트학회논문집
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    • 제13권4호
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    • pp.305-313
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    • 2001
  • 본 연구에서는 콘크리트 열전도율의 영향인자에 대하여 TLPP원리를 응용한 QTM-D3 장비를 이용하여 실험을 실시하였고, 이들 실험결과를 이용하여 콘크리트의 열전도율을 예측하는 모델식을 제안하였다. 본 연구를 통하여 얻은 결론은 다음과 같다. 콘크리트, 모르타르 및 페이스트의 열전도율에 미치는 주요 영향인자를 구명하기 위해 본 연구에서 선택된 실험변수는 재령, 골재 함유량, 시멘트 함유량, 결합재 종류, 잔골재율, 시편의 온도 및 함수상태로 총 7가지이다. 이중에서 골재 함유량과 함수상태가 콘크리트 열전도율의 주요 영향인자임을 알 수 있었다. 그리고 시멘트 사용량이 많은 페이스트나 모르타르의 경우 시멘트 함유량이나 결합재 종류에 의해서도 열전도율이 영향을 받고 있다. 그러나 재령은 콘크리트의 열전도율에 큰 영향을 미치지 않음을 알 수 있었다. 콘크리트 열전도율에 주요 영향인자인 골재 함유량, 잔골재율, 시편의 온도 및 함수상태를 이용하여 콘크리트의 열전도율을 계산할 수 있는 모델식을 제안하였다.

열전달 매질을 고려한 에너지파일의 열전달 거동 분석 (Heat Transfer Analysis of Energy Pile Considering heat transfer medium)

  • 김도현;정상섬;송진영
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 춘계 학술발표회
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    • pp.963-970
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    • 2010
  • In this study, a series of thermal numerical analysis was conducted through the ground condition and the length and shape of the energy pile. In order to investigate the effect of the thermal properties of ground condition, grout and pile type on heat transfer efficiency in the U-type heat exchanger in energy pile, thermal numerical analysis was done by using ABAQUS. ABAQUS, a finite element analyzing program, was employed to evaluate the temperature distribution on the cross section of energy pile system incorporating HDPE - grout - pile - Ground condition which consists of clay, sand, rock type soil and ground water.

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가정용 흡수식 냉온수기용 냉각탑의 성능특성 (Performance Characteristics of Cooling Tower on Small Absorption Chiller)

  • ;김은필;정석권;민경현;김재돌;윤정인
    • Journal of Advanced Marine Engineering and Technology
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    • 제28권7호
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    • pp.1145-1151
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    • 2004
  • The experiment of thermal performance about cross flow type cooling tower was conducted in this study. Generally the ambient air condition can affect the thermal performance of cooling tower to improve or not. However it is hard to control the cooling water temperature that we want under bad air condition or during rainy season. In this paper, the effect of variables, which the ambient air have. especially wet-bulb temperature, are experimentally investigated for controlling the cooling water temperature more successfully. The result is that there is appropriate air flow rate in respective air condition to preserve the cooling performance in the cooling tower and the maximum air flow rate can't overcome the approach under bad air condition.

그리스윤활 고속주축의 예압과 냉각조건에 따른 열특성의 실험적 고찰 (Experimental study on the thermal charateristics according to the pre-load and cooling condition for the high speed spindle with grease lubrication)

  • 최대봉;김수태;정성훈;김용기
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2003년도 추계학술대회
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    • pp.41-46
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    • 2003
  • The important problem in high speed spindles is to reduce and minimize the thermal effect by motor and bail bearings. Thermal characteristics according to the bearing pre-load and cooling condition are studied for the test spindl with grease lubrication and high frequency motor. Bearing and motor we main heat generation, and heat generation by ball bearings as a function of load, viscosity and gyroscopic moment effect are considered. Temperature distribution and thermal displacement according to the speed of spindle are measured by thermocouple and gap sensor. The results show that the fitting pre-load and cooling temperature are very effective to minimize the thermal effect by motor an ball bearings.

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매트기초의 온도균열에 미치는 시공조건의 영향에 관한 연구 (A Study on the Effect of the Construction Conditions on a Thermal Crack of Mat Foundation)

  • 이도범;김효락;최일호
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2003년도 학술.기술논문 발표회
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    • pp.1-4
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    • 2003
  • Recently, a structure has been larger and higher under the improvement of construction technique. So, a concrete constructions that a mat foundation thickness of structure is over 80cm have been many. Also, because of the reason high strength concrete, the matter of thermal crack have become an important task to be solved absolutely. In a cause a thermal crack occurrence, there used, mixture of concrete, construction and so forth. In this study, we executed temperature and stress analysis of mat foundation to know the effect the construction condition a thermal crack of mat foundation. And we evaluated quantitatively about the occurrence possibility of thermal crack using the hydration heat analysis program. By using of this analysis technique, will can control skilfully the quality of a mat foundation in advance.

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가구 유형에 따른 여름철 공동주택의 실내온열환경과 냉방 조절 행위에 관한 연구 (Research on Indoor Thermal Environment and Residents' Control Behavior of Cooling according to Household Type in Apartment)

  • 배치혜;배누리;전정윤
    • 한국주거학회논문집
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    • 제19권1호
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    • pp.89-96
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    • 2008
  • This study measured the thermal environment and residents' control behaviors of cooing according to 3 groups of household type-families with preschool children, families of middle age and families of senior. The object of this study are to fmd the difference of the actual condition of indoor thermal environment and cooling control behavior by age or household type and to develop user oriented climate control system. The results were summarized as follows. When the age of members at household is younger, the indoor mean temperature and temperature that people turned off the air conditioner became lower. These different indoor thermal environment of each group means that younger generation is familiar with cooler from their early age and these early uses of cooler made them prefer cooler condition than family of senior. Therefore, this results show that different indoor thermal environment is influenced by factors such as household type and metabolism difference and so on.

연속주조 몰드의 구조해석 (Structural Analysis of Continuous Casting Mold)

  • 원종진;이종선;홍석주
    • 한국공작기계학회논문집
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    • 제10권4호
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    • pp.104-110
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    • 2001
  • The objective of this study is structural analysis of continuous casting mold. A two-dimensional finite element model was developed to compute the temperature distribution, thermal stress and thermal strain behavior for continuous casting mold. Structural analysis was made using thermal analysis result, utilizing transient analysis of ANSYS. This structural analysis results, many variables such as casting speed, cooling condition film coefficient, convection and load condition are considered.

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