• Title/Summary/Keyword: Thermal Environment

Search Result 2,954, Processing Time 0.035 seconds

Development of an assessment tool for outdoor thermal environment (옥외 온열환경 평가시뮬레이션 기법의 개발)

  • Jee, Yong-Seung;Hwang, Hyo-Keun;Lim, Jong-Yeon;Song, Doo-Sam
    • 한국태양에너지학회:학술대회논문집
    • /
    • 2009.11a
    • /
    • pp.38-43
    • /
    • 2009
  • Since most of the existing CFD simulation about thermal environment was limited as indoor environment, it is not appropriate to adopt the same method for external thermal environment, because the solar radiation highly affect the outdoor thermal environment. Thus, in case of assessing the outdoor thermal environment, the radiation calculation is very important. In this study, as a new method to evaluate the outdoor thermal environment, coupled simulation of convection and radiation will be proposed.

  • PDF

Development of Methods for Evaluation of Indoor Thermal Environment of Apartment Housing (공동주택의 실내 열환경에 대한 평가방법개발)

  • 윤정숙
    • Journal of the Korean Home Economics Association
    • /
    • v.35 no.6
    • /
    • pp.101-110
    • /
    • 1997
  • The intent of this study is to propose a method for appraisal of the indoor thermal environment of apartment housing by measuring physical factors and residents' response to questionnaire survey. The experiments were performed on eight houses each in summer (August 18 through 31,1995) and winer (february 16 through 20,1996). It included measurements of indoor air temperature, globe temperature, relative humidity, and CO2 concentration. The questionnaire surveys were performed each in summer (July 16 through 20, 1996) and winer (February 13 through 16, 1996). And 248 cases in summer and 297 cases in winter were used in analysis. These questionnaire surveys asked residents' response about thermal sensation, humidity sensation, sense of air freshness regarding the indoor thermal environment. data acquired through the experiments and questionnaire surveys were then transferred to scales that allowed relative comparison, and measured to an appraisal standard chart. Appraisal tools included appraisal charts and radar charts. Indoor thermal environment was judged to be positive according to experiments, but residents appraised the thermal environment to be average. This difference between the two can be found in the strict standards by which residents judge the thermal environment of their apartments.

  • PDF

Study on the Subway Platform Thermal Environment for using Natural Energy (자연에너지 활용을 위한 지하철 승강장 열환경에 관한 연구)

  • KIM, Hoe-Ryul;KIM, Dong-Gyu;KUM, Jong-Soo;CHUNG, Yong-Hyun;PARK, Sung-Chul
    • Journal of Fisheries and Marine Sciences Education
    • /
    • v.21 no.2
    • /
    • pp.269-277
    • /
    • 2009
  • Ventilation equipment performs a central role to maintain comfort subway environment. So ventilation equipment of Busan subway line No.1 is required to improve thermal environment. In this study, conditions of thermal environment are presented to improve ventilation equipment at existing subway station platforms by measuring thermal environment of platforms operated ventilation equipment at 14 stations of Busan subway line No.1. AWS of data in comparison with the neighbouring platforms and thermal environment analysis. Thermal environment status of subway platform analysis results are as follows. 1)Daytime platform temperature was higher than outdoor temperature, but night time platform temperature was lower than outdoor temperature. 2)Train wind had effect on improving thermal comfort in platform. 3)When outdoor temperature is below $24^{\circ}C$, inlet air is able to lower than platform temperature. 4)Considering existing ventilation system, night purge systems is useful to improving platform thermal environment.

Analysis of On-orbit Thermal Environment of Earth Orbit Satellite during Mission Lifetime (지구궤도 인공위성의 임무기간 중 궤도 열 환경 분석)

  • Kang, Soojin;Yun, Jihyeon;Jung, Changhoon;Park, Sungwoo
    • Journal of Aerospace System Engineering
    • /
    • v.14 no.1
    • /
    • pp.36-43
    • /
    • 2020
  • The start of satellite thermal design was to predict the worst operating environment through analysis of the thermal environment of the operation orbit. Because the satellites have different types of operating trajectories for their mission, the exposed thermal environment also varies. Thus, it is necessary to analyze in consideration of the orbital conditions, and a design was performed to guarantee thermal stability for the worst case defined through the analysis. The orbital thermal environmental analysis required an understanding of the basic orbit mechanics and the heat exchange relationship between the space environment and satellite. The purpose of this paper was to provide an understanding of the orbital thermal environment analysis by providing basic data on the space thermal environment in the earth-orbit and describing thermal relations that calculate the amount of space heat inflow into satellites. Additionally, an example of a virtual satellite shows the overall process of analyzing the orbital thermal environment during a mission lifetime.

Thermal Comfort in Outdoor Environment by Questionnaire Survey : Using the Logistic Regresstion (로지스틱 회귀분석을 활용한 옥외공간에서의 온열쾌적감에 대한 피험자 설문 분석)

  • Lim, Jong-Yeon;Hwang, Hyo-Keun;Ryu, Min-Kyung;Song, Doo-Sam
    • 한국태양에너지학회:학술대회논문집
    • /
    • 2009.04a
    • /
    • pp.97-101
    • /
    • 2009
  • Calculating and predicting the thermal comfort in outdoor environment are difficult than in indoor environment because composition parameters are variable, interrelations among parameters are very complex and human activities in outdoor are diverse. Moreover, the thermal expectancy of subject in outdoor environment is different from that of indoor environment. The aims of this study are to examine the difference between indoor and outdoor thermal comfort range. With this in mind, field measurement for estimating outdoor thermal environment and a questionnaire survey with simultaneous measurement around the subject were conducted.

  • PDF

Study on assessment of outdoor thermal environment with coupled simulation of convection and radiation (대류.복사 연성시뮬레이션을 통한 옥외 온열환경 평가 기법)

  • Ryu, Min-Kyung;Lim, Jong-Yeon;Hwang, Hyo-Keun;Song, Doo-Sam
    • Proceedings of the SAREK Conference
    • /
    • 2009.06a
    • /
    • pp.565-572
    • /
    • 2009
  • Deterioration of the outdoor thermal environment in urban areas such as heat island has become worse due to urbanization and overpopulation, etc. In this study, a new method which is coupled simulation of convection and radiation to evaluate outdoor thermal environment in urban area will be proposed. Because the solar radiation affects on outdoor thermal environment massively, therefore the radiation calculation is very important in outdoor thermal environment prediction. The coupled simulation proposed in this study can assess the outdoor thermal environment with accurate.

  • PDF

The Thermal Environment and Thermal Reaction in the Radiant Floor Heating System (바닥난방의 온열환경 및 열적반응에 관한 연구 -방바닥에 누운 상태를 중심으로-)

  • 이무진
    • Journal of the Korean housing association
    • /
    • v.10 no.1
    • /
    • pp.75-84
    • /
    • 1999
  • The purpose of this study is to identify the characteristics of the thermal environment, and to analyze the relationship between the thermal reactions and the skin temperatures in the lying position in the radiant floor heating system. The results are as follows: 1) The globe temperature was nearly equal to the operative temperature in the room. 2) The floor surface temperature and the globe temperature were 26.4$^{\circ}C$ and 23.6$^{\circ}C$, respectively when the whole body temperature was at neutral point. 3) The mean temperature of the six skin parts was 31.3$^{\circ}C$ (cold thermal environment); 34.1$^{\circ}C$ (neutral thermal environment); 35.1$^{\circ}C$ (hot thermal environment).

  • PDF

A Field Survey of Thermal Comfort in Office Building with Thermal Environment Standard (온열환경기준에 따른 여름철 사무실의 열쾌적성 평가)

  • Kong, Hyo-Joo;Yun, Geun-Young;Kim, Jeong-Tai
    • KIEAE Journal
    • /
    • v.11 no.3
    • /
    • pp.37-42
    • /
    • 2011
  • This study aims to analyze the field survey of thermal comfort in office building with national thermal environment standard. Internal and external temperatures were measured at ten minute intervals and compared in accordance with the national standard for thermal environment. Sixty two workers filled in the questionnaire survey forms five times a day for 40 days. Field monitoring of offices in Seoul, Korea were conducted from 20 July to 28 August. Result for the comfort temperature was set a $26.30^{\circ}C$. This indicates that the 26 degree is reliable for the Korean standard. Indoor temperature standard can reduce energy use by air-conditioned buildings and the temperature would be offer comfort to occupants.

Thermal Environment Analysis of a Classroom by CFD Simulation to Determine Optimal Temperature Sensor Position in Ceiling Type Air-Conditioning System (천정형 에어컨 온도센서의 최적 위치 결정을 위한 교실의 CFD 열환경 분석)

  • Li, M.H.;Kim, D.G.;Kum, J.S.;Jeong, S.K.
    • Journal of Power System Engineering
    • /
    • v.10 no.4
    • /
    • pp.43-49
    • /
    • 2006
  • Nowadays, the thermal environments of classrooms are usually adjusted by the ceiling type air-conditioning system with a temperature sensor installed on inlet of an air-conditioner. However, it is not clear that the conventional temperature sensor position is proper to satisfy both thermal comport and energy saving in summer especially. Therefore, this study is aimed at finding out the best position of the temperature sensor on the purpose of the comfort thermal environment and energy saving. The different 5 positions for the temperature sensor are supposed in this paper to analyze thermal environment by CFD. From the analysis through the CFD simulations, the best position of the temperature sensor satisfying for both comfort thermal environment and energy saving is obtained.

  • PDF

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

  • Bae, Chi-Hye;Bae, Nu-Ri;Chun, Chung-Yoon
    • Journal of the Korean housing association
    • /
    • v.19 no.1
    • /
    • pp.89-96
    • /
    • 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.