• Title/Summary/Keyword: Thermal environment

Search Result 2,941, Processing Time 0.037 seconds

Evaluation of the Thermal Environment and Comfort in Apartment complex using Unsteady-state CFD simulation (Unsteady-state CFD 시뮬레이션을 이용한 여름철 공동주택 외부공간의 온열환경 및 쾌적성 평가)

  • Jeon, Mi-Young;Lee, Seung-Jae;Kim, Ji-Yoeng;Leigh, Seung-Bok;Kim, Taeyeon
    • KIEAE Journal
    • /
    • v.10 no.4
    • /
    • pp.67-73
    • /
    • 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.

Development and application of an assessment tool for outdoor thermal environment (옥외 온열환경 평가를 위한 복사 연성 CFD 해석기법의 개요)

  • Lim, Jong-Yeon;Chang, Hyun-Jae;Song, Doo-Sam
    • Journal of the Korean Solar Energy Society
    • /
    • v.29 no.6
    • /
    • pp.45-55
    • /
    • 2009
  • Deterioration of the outdoor thermal environment in urban areas has become worse and worse due to the urbanization and overpopulation, etc. Most of existing researches about thermal environment are focused on the indoor environment in which the radiation heat exchange is relatively constant. However, the outdoor thermal environment is changed with time passages, because the thermal environment is highly effected by solar radiation. Thus, to simulate the outdoor thermal environment with accuracy, the solar radiation calculation should be considered, and the radiation heat exchange between building surface and ground surface should be calculated. The purpose of this study is to develop the simulator that can be possible to evaluate the outdoor thermal environment and pedestrian thermal comfort. In this paper, a new method which is coupled with convective heat transfer simulation and radiative heat transfer simulation will be proposed. And the coupled simulation method will be described through case study for outdoor thermal environment. From the results of simulation, the coupled simulation proposed in this study can assess the outdoor thermal environment with accuracy.

Change of thermal environment in buildings by wind direction (풍향에 따른 건물군에서의 열환경 변화)

  • Kim, Sang-Jin
    • KIEAE Journal
    • /
    • v.12 no.3
    • /
    • pp.27-32
    • /
    • 2012
  • In recent years, the quality of the outdoor thermal environment has come to be regarded as important as that of the indoor thermal environment. Since the outdoor thermal environment is composed of many elements and is affected by many factors, it is not easy to evaluate the impact of each factor separately. Hence, a comprehensive assessment method is required. In order to evaluate the pedestrian level comfort of an outdoor climate, it is necessary to investigate not only wind velocity but also various physical elements, such as temperature, moisture, radiation, etc. Prediction of wind and thermal environment for a large scale buildings is one of the most important targets for research. Wind and thermal change in a city area is a very complicated phenomenon affected by many physical processes. The purpose of this study is to develop a design plan for wind environment at a large Buildings. In this study, we analyze outdoor wind environment and thermal environment on buildings using the CFD (Computational Fluid Dynamics) method. The arrangement of building models is an apartment in Jeonju. These prediction of wind and thermal environment for a large scale buildings is necessary in a plan before a building is built.

Study on Development of Environmental Attention Assessment Applied in the Elementary Classroom (초등학교 교실에서 적용한 환경주의력 평가기법 개발에 관한 연구)

  • Jeong, Ji-Won;Lee, Hee-Kwan
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.32 no.6
    • /
    • pp.624-632
    • /
    • 2016
  • Attention plays vital role either students academic performance in classroom or work performance of workers. This study was accomplished among elementary school students of elementary school classroom for two years. Three experiment cases were designed based on the Predicted Mean Vote (PMV) indexes. Thermal environment and PMV were directly monitored; Thermal Sensation Vote (TSV) and Comfort Sensation Vote (CSV) were analyzed based on survey data; and attention was analyzed for different comfort level using FAIR program. PMV, TSV and CSV were varied with the change in thermal environment and there was not noticeable gender influence on impact. The good correlation between thermal environment, PMV, TSV and CSV confirmed the impact of thermal environment on indoor comfort. There were different impacts on attention with comfort conditions. Academic attention of low attention group i.e. weak students, can be improved by providing the comfort environment. Thermal environment influences the comfort and the comfort influences the attention, it is possible to assess the impact of thermal environment on attention in further.

Development and Evaluation of a PMV Sensor for the Control of Indoor Thermal Environment (실내 온열환경 제어를 위한 PMV 센서의 개발 및 적용성 평가연구)

  • 윤동원;강효석;안병욱
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.15 no.10
    • /
    • pp.870-878
    • /
    • 2003
  • The maintenance of thermal equilibrium between the human body and its environment is one of the primary requirements for health, wellbeing and comfort. For the effective control of indoor thermal environment, thermostat or humidistat is used. But, it is not sufficient to control the indoor thermal environment using only one or two parameters as human response for the indoor comfortable environment. So an environmental thermal index is required for the control of indoor thermal environment effectively. In this study, a PMV sensor has been developed which has integrated from various kinds of individual sensors for temperature, humidity, air velocity, radiant temperature. After applying the PMV and PPD equation, it is possible to monitor the indoor thermal environment with the sensor system, which is adopted to the circuit for optimization according to the human response with the metabolic rate and activities. The measurement was carried out to verify the performance of the integrated sensor system in comparison with existing measurement system, the PMV meter. As a result, the possibility of applying the PMV sensor to control the indoor thermal environment simultaneously was examined.

Comparative Legal Study of Workplace Thermal Environment Management Legislation (작업장 온열환경 관리 법제의 비교법적 고찰)

  • Saemi Shin;Hea Min Lee;Nosung Ki;Sang-Hoon Byeon;SunghoKim
    • Journal of Korean Society of Occupational and Environmental Hygiene
    • /
    • v.33 no.4
    • /
    • pp.485-501
    • /
    • 2023
  • Objectives: The Ministry of Employment and Labor has revised the articles regarding management of the thermal environment in the workplace. Currently, two types of regulations exist together with indoor workplaces as the scope of application. It appears that the time has come to discuss regulations. In this study, we aim to identify the feasibility of and problems with the current system through a comparative legal review of workplace thermal environment management laws from around the world. We suggest directions for improving South Korea's workplace thermal environment management laws. Methods: For the several selected countries, we analyzed the classification and content of obligations stipulated for the thermal environment, the presence or absence of specific measures for thermal environment management, legal status and content, and the scope of application of thermal environment provisions and measures. The investigated content was classified according to Zweigelt-Kotz's legal theory. Results: In some countries, employers' obligations for regulating the thermal environment are broadly divided into two types: results and actions. The scope of application of provisions and measures on the thermal environment was extensive, with most of the selected countries targeting general workplaces. Conclusions: In the case of South Korea, restricting and classifying target workplaces and imposing separate obligations to manage a workplace thermal environment goes against global practices, and stipulating legal orders and separate action obligations in guidelines does not conform to the characteristics of South Korea's legal system, meaning that improvement is needed.

Evaluation of Indoor Thermal Environment for Cooling in Apartment House (공동주택의 냉방시 실내온열환경 평가 연구)

  • 김난행;안병욱
    • Journal of the Korean housing association
    • /
    • v.14 no.3
    • /
    • pp.1-8
    • /
    • 2003
  • It is not sufficient to control the indoor thermal environment using only one or two parameters by itself as human response for the control of indoor thermal environment. So a proper environmental thermal index is required for the control of indoor thermal environment effectively. In this study, the physical environment was measured and analysed and the skin temperature of the subjects and their response were investigated to evaluate the optimum thermal comfort range for cooling season in an apartment house. As a result, the optimal temperature was 26.1$^{\circ}C$ and the temperature ranges which more than 80% responded as satisfactory were 24.1~28.$0^{\circ}C$, respectively. As the OT had most significant interrelation with the PMV, it is desirable to use the OT in evaluating the thermal environment during cooling. Also, the comfort range was concluded between OT 25.5~27.3$^{\circ}C$ by appointing the PMV of -0.5~0.5 as the optimum comfort condition. In addition, the Human responses were compared with calculated PMV, OT and MRT and the relationships are suggested in order to utilize to control indoor thermal environment.

Monitoring of Urban Thermal Environment Change in Daejun Using Landsat TIR Satellite Data (Landsat 열적외 영상자료를 활용한 대전시 열 환경 변화 모니터링)

  • Choi, Jin-Ho;Cho, Hyun-Ju;Jong, Hoan-Do
    • Journal of Environmental Impact Assessment
    • /
    • v.22 no.5
    • /
    • pp.513-523
    • /
    • 2013
  • This purpose of this work is to explore the characteristics of urban thermal environment distribution with the case of Daejeon. To do that, this work applied GIS Spatial Statistics to the LandSAT images gathered from 2000 to 2011. The urban thermal environment distribution at the time point of 2 showed high spatial autocorrelation. Therefore, it is judged that spatial autocorrelation is needed to increase the reliability and explanatory power of the characteristics of thermal environment distribution. In the case of the thermal in Daejeon, its positive clustering appeared high at the time point of 2, and its clustering in 2011 more gradually decreased than that in 2000 to 2011. In particular, given the decrease in the core H-H region, it was found that the thermal environment of Daejeon was greatly improved. However, since the rise in the region L-L means another changed like construction of a new city, it is judged that it is necessary to come up with a proper plan. It is considered that this analysis of the characteristics of urban thermal environment distribution in consideration of spatial autocorrelation L-L be useful for providing a fundamental material necessary for the policy and project of thermal environment improvement.

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

  • 김태연;이윤규
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.16 no.2
    • /
    • 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.

An Analysis of Indoor Thermal Environment by Macro Model (매크로 모델에 의한 실내온열환경 검토)

  • Jung, Jae-Hoon
    • Proceedings of the SAREK Conference
    • /
    • 2008.11a
    • /
    • pp.584-589
    • /
    • 2008
  • It is known that slab thermal storage which uses concrete slab as thermal material is effective in the load leveling and using the nighttime electric power. The temperature distribution is not constant in plenum in thermal storage time by beams, ducts such as several factor. It is considered that this fact will effect on efficiency of thermal storage and indoor thermal environment. The purpose of this paper is to examine the thermal environment inside plenum. A macro model was made for the analysis of indoor thermal environment as the first step. The flow rate distribution and temperature distribution of object room model was examined by use of basic equations such as airflow by the pressure difference between unit cells, heat flow by air and heat transfer.

  • PDF