• 제목/요약/키워드: Thermal-Comfort

검색결과 700건 처리시간 0.034초

CFD 연성해석과 유전자 알고리즘을 이용한 실내 열환경 최적설계에 관한 연구 (Optimal Design for Indoor Thermal Environment based on CFD Simulation and Genetic Algorithms)

  • 김태연;이윤규
    • 설비공학논문집
    • /
    • 제16권2호
    • /
    • pp.111-120
    • /
    • 2004
  • The optimal design method of indoor thermal environment using CFD coupled simulation and genetic algorithms (GA) is developed in this study. CFD could analyze the thermal environment considering the distribution of temperature, velocity, etc. in a room. Therefore, It would be appropriate to use CFD for the optimal design method considering their distribution. In this paper, the optimal design means the most appropriate boundary conditions of the room among the conditions where the design target of indoor therm environment is achieved. Two step optimal indoor thermal environment design method is proposed. It includes the GA for searching the optimal indoor thermal environment design. To examine the performance of this method, the optimal design of hybrid ventilation system, which uses the natural cross ventilation and the radiation-cooling panel is conducted. The optimal design which satisfies the design target (thermal comfort, minimum cooling load, minimum vertical temperature difference) is found using two step optimal design method.

The Effect of Spacer on Microclimate and Comfort Sensation in Protective Clothing for Firefighters

  • Chung, Gi-Soo;Lee, Dae-Hoon
    • 한국의류산업학회지
    • /
    • 제4권6호
    • /
    • pp.564-566
    • /
    • 2002
  • Protective clothing for firefighters typically consists of a flame resistant outer shell and inner layers. The inner layers are generally composed of a moisture barrier and a thermal barrier. On performing the task in fire place the heat and perspiration generated from the body become trapped inside the protective clothing. Those heat and moisture result into heat-stress and physical fatigue of fire fighter, which hinder the work. Therefore, the system of clothing designs and material layers must be chosen carefully to balance protection and comfort. 3 kinds of protective clothing of 3 layer structure were used in the experiment of physiological comfort. From the comparison of wear trials with the 3 kinds of layers in firefighters clothing, it indicates that the moisture dissipation of A+B2+C was highest, following A+BI+C andA+B3+C. And the heat dissipation of A+BI+C and A+B2+C were better than A+B3+C. In the protective clothing with A+B3+C, heat and perspiration generated through exercise remained in clothing system long and caused discomfort.

Velvet 직물의 인체 착의 실험을 통한 착용감 연구 (A Study on the Wearing Comfort in Velvet Fabrics)

  • 조지현;류덕환;이욱자
    • 한국생활과학회지
    • /
    • 제5권2호
    • /
    • pp.123-130
    • /
    • 1996
  • The purpose of this study is to examine and to evaluate the wearing performance of pile materials to produce velvet fabrics which have excellent wearing comfort. Acetate velvet, Cuprammonium rayon velvet were combined as textiles for clothing and acetate and viscose rayon were as textiles for lining at the environmental condition of temperature $15^{\circ}C,\;18^{\circ}C,\;21^{\circ}C,\;24^{\circ}C$, relative humidity $50{\pm}5%$ and air velocity 0.25 m/sec. Wearing comfort among 4 materials combinations(Aa, Av, Ra, Rv) was examined and compared. The results are as follows. The investigation of mean skin temperature for environmental temperature and material combinations showed that the mean temperature had a significant difference at the p<0.01 level in accordance with environmental temperature and material combinations.(Aa>Av>Ra>Rv) Moreover, in clothing climate only clothing temperature tended to increase almost linearly but at $24^{\circ}C$ there was no significant difference among textiles for lining compared with the other environmental temperatures. In subjective sensations thermal sensation and comfort sensation showed a significant difference in environmental temperatures and materials.(Aa>Av>Ra>Rv) Though a subject felt warmer, more humid, and more uncomfortable at $24^{\circ}C$ for all of the material combinations comparing with the other temperatures, there was no significant difference in materials.

  • PDF

태권도복 소재의 성능 및 착용감의 개선을 위한 연구 (A Study on the Improvement in Performances and Wearing Sensation of Textiles for Taekwondo Wears)

  • 전영민;박정희;최정화
    • 한국의류학회지
    • /
    • 제27권1호
    • /
    • pp.134-142
    • /
    • 2003
  • Performances of Taekwondo fabrics were evaluated in respect of fiber component. yarn count, weave structure and wearing comfort. As a beginning step, we investigated the present situation of Taekwondo wears by questionnaire from pro and amateur Taekwondo players. Samples employed in this study were cotton/nylon blend fabric that was newly woven for this study as well as fabrics of current Taekwondo wears for sale in the market. Their fundamental properties measured were such as air permeability, water vapor transport. wickability, absorption rate, Qmax values, thermal conductivity, durability, hand value, and etc. In addition, subjective wearing sensations were evaluated using Taekwondo wears made of those fabrics. From the results of the objective measurement and the subjective wearing test, we estimated the total fitness of fabrics as a Taekwondo wear. From the questionnaire we could see that pro players and amateurs wanted highly absorbing, quick drying, and soft-tough and complained abrasive surfaces and static elasticity of current fabrics. In view of the results so far achieved, nylon blended fabrics newly woven in this study, showed better comfort-related properties from both of the objective and subjective tests. It was also represented that finer yams enhanced water absorption and touch, and fabrics with rough surface such as honeycomb weave was superior in wearing comfort as well as aesthetic appearance.

이중양면편 스포츠용 소재의 착용쾌적성 평가 (Wear Comfort of Double Jersey for Sports Wear)

  • 정수경;홍경희
    • 한국생활과학회지
    • /
    • 제12권2호
    • /
    • pp.253-263
    • /
    • 2003
  • The purposes of this study were to find out an evaluation scale that could predict wear comfort and to investigate the effect of the skin-contacting fiber type on the subjective sensation and microclimate. Sensorial evaluation was basically followed by the Human Perception Analysis (HPA) interviewing 144 consumers. Sixteen female subjects were participated in the sleeve wear test with and without wearing vapor permeable water repellent outerwear. Experimental sleeves were constructed using the same double knit by turning inside out to control other material effects except the skin-contacting fiber type, hence each different side of double knit, cotton side and the cotton/polypropylene blend side, was next to skin in each trial of the experiment. As results, it was noted that the term representing a combined feeling of thermal and wetness sensation, and muggy appeared to be a powerful language to measure perceptual responses of human subject among five dimensions of evaluation. although the ordinary users did not use the term very often. As for the comfort properties of double knits, it seemed that subjects slightly more preferred polypropylene/cotton blend to cotton as the skin-contacting fiber type when they wore outerwear and their skin were covered with sweat, although the result was rot statistically significant and need to be confirmed under higher work load.

  • PDF

UAV 영상과 ENVI-met 활용 물리적 환경과 열적 환경 비교 (Comparing Physical and Thermal Environments Using UAV Imagery and ENVI-met)

  • 김성현;박경훈;송봉근
    • 한국지리정보학회지
    • /
    • 제26권4호
    • /
    • pp.145-160
    • /
    • 2023
  • 본 연구는 무인항공기(Unmanned Aerial Vehicles, UAV) 기반 물리적 환경인 Normalized Difference Vegetation Index(NDVI), Sky View Factor(SVF)와 ENVI-met 모델링을 활용하여 시간대별 열적 환경을 비교 분석하는 것을 목적으로 수행하였다. 연구 결과 NDVI, SVF는 열적 환경 요소인 Upward short-wavelength(S↑), Downward short-wavelength(S↓), Upward long-wavelength(L↑), Downward long-wavelength(L↓), Land Surface Temperature (LST), Mean Radiant Temperature(Tmrt)와 유의수준 1% 이내에서 모두 상관관계를 보이는 것으로 도출되었다. 특히, NDVI는 S↑와 12시에 최대 -0.52**의 상관관계를 가지는 것으로 분석되었고, L↓와 모든 시간대에서 0.53** 이상의 상관성을 보였다. LST와는 -0.61**(13시)의 상관성을 보여 NDVI는 장파 복사에너지의 관련성이 높은 것으로 판단된다. SVF의 경우 SVF 범위에 따라 장파 복사에너지와의 관련성이 높은 것으로 도출되었다. 본 연구결과는 공간의 열적 쾌적성과 미기후를 평가하기 위한 통합 접근 방식을 제공할 수 있으며, 도시 디자인 및 경관 특성이 보행자의 열 쾌적성 미치는 영향 관계 규명 등에 활용될 수 있을 것으로 판단된다.

도시열환경 개선 및 보행자 열 쾌적성 증대를 위한 효율적 가로녹지 조성방안 연구 - 계획 및 설계를 위한 매개변수 도출과 녹지조성 방법 제안을 중심으로 - (A Study on Efficient Sidewalk Green Space Development for Improving Urban Thermal Environments and Enhancing Pedestrian Comfort - Focused on the Derivation of Parameters for Design, and Proposing Methods for Green Space Creation -)

  • 박주현;엄정희
    • 한국조경학회지
    • /
    • 제52권2호
    • /
    • pp.21-38
    • /
    • 2024
  • 본 연구는 문헌 고찰을 통해 도시 열환경 개선 및 보행자 열쾌적성 증대를 위한 효율적인 가로녹지 조성방안을 제안하는 것이 목적이다. 특히, 녹지 계획 및 설계에 활용가능한 매개변수를 도출하고, 매개변수별로 열환경 완화 매커니즘을 분석한 후, 이를 바탕으로 녹지 계획 및 설계 시 활용가능한 수종선택 방법 및 녹지조성 방법을 제안하였다. 이를 위해 국내외 관련 논문 중 4단계 과정을 통해 고찰하고자 하는 61개의 논문을 선정하였으며, 선정된 논문을 분석하여 다음과 같은 주요 결과를 도출하였다. 열스트레스가 높은 종횡비 낮고 천공률이 높은 오픈된 거리협곡의 경우, 그늘의 양과 질을 높이기 위해 수관폭이 넓고, 수고가 높고, 지하고가 낮고, 엽면적 지수가 높고, 수관의 녹량이 많은 활엽수를 다열의 좁은 간격으로 다층식재하는 것이 열저감에 효과적이다. 반면 열스트레스가 비교적 적은 종횡비가 높고 천공률이 낮은 깊고 좁은 거리협곡의 경우, 거리협곡 내 환기력을 높이기 위해 수관폭이 좁고, 지하고가 높고, 수관높이가 낮고, 엽면적 지수가 낮은 활엽수를 넓은 간격으로 식재하는 것이 열저감에 효과적이다. 본 연구는 거리협곡 내 열환경 개선 및 보행자 열쾌적성 증대를 위한 가로녹지 조성의 기초자료로 활용할 수 있으며, 녹지의 위치 선정 및 우선순위 선정 시 기초자료로 활용할 수 있다. 나아가 기후변화 대응을 위한 녹지 계획 및 설계를 위한 가이드라인 작성 시 기초자료로 활용될 수 있을 것으로 기대한다.

치환환기되는 실내에 있어서 인체주변의 기류 및 온열환경 특성에 대한 검토 (Examination of Airflow and Thermal Environment Characteristic around Human Body in a Room with Displacement Ventilation)

  • 양정훈
    • 설비공학논문집
    • /
    • 제19권4호
    • /
    • pp.299-306
    • /
    • 2007
  • Recently, the numerical analysis using person shape model for CFD (Computational Fluid Dynamic) has been researched widely for the thermal comfort and inhaled air quality of human body in the indoor environments. The purpose of this research is to examine the characteristic of airflow and thermal environment around human body by the experiment of displacement ventilation that assumes the indoor environment of natural convection. In this study, thermal manikin was used instead of real human body. The Airflow characteristic around human body was measured in precision by PIV (Particle Image Velocimetry). This experimental result will be used as data for CFD benchmark test using person shape model.

PET직물의 감량율과 직물구조인자에 따른 열적 쾌적성 변화에 관한 연구 (A Study on the Thermal Comfort to the Weight Reduction Rate and Fabric Structural Parameters of PET Fabrics)

  • 이희준;이민수;김승진;조대현;김태훈
    • 한국의류학회지
    • /
    • 제22권7호
    • /
    • pp.816-825
    • /
    • 1998
  • This study surveys the thermal property and air permeability to the weight reduction rate of PET fabrics. For this purpose, 12 kinds of satin and 18 kinds of plain weave fabrics are prepared with change of the physical properties such as weft yarn count, t.p.m. and density. The weight reduction rate was 0%, 12%, 25% and 30%. The warm/cool feeling(Qmax), thermal insulating value(T.I.V.) and thermal conductivity(K) were measured by KES-F7 System and discussed in relation with the weight reduction rate, weft yarn linear density, t.p.m., weft density of fabric and weave structure.

  • PDF

겨울철 난방시 아파트 구조체의 축방열 특성에 대한 연구 (A Study on Characteristics of Heat Storage and Emission of Apartment Structures in Winter Season)

  • 조근제;장현재
    • 한국태양에너지학회:학술대회논문집
    • /
    • 한국태양에너지학회 2011년도 추계학술발표대회 논문집
    • /
    • pp.208-213
    • /
    • 2011
  • In the former study, it is obtained that thermal storage effect of the apartment structure is the disadvantage to maintain comfort indoor thermal environment. However, because the thermal storage effect can be changed of its aspect in heating season, field measurement at the same apartment with the measurement in summer season was conducted in winter season. As results, thermal storage effect of apartment structure was the disadvantage in winter season, too.

  • PDF