• Title/Summary/Keyword: Room air

Search Result 1,752, Processing Time 0.028 seconds

Effect of Contaminant Source Location on Indoor Air Quality

  • Lee, Hee-Kwan;Kim, Shin-Do
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.14 no.E
    • /
    • pp.1-7
    • /
    • 1998
  • This paper presents an experimental study for understanding the indoor air quality in a room. A model room, which had a ceiling-mounted supply and a sidewall-mounted exhaust, was used to examine the effect of air exchange rate (AER) and contaminant source location (CSL) as a function of the elapsed time. A tracer gas method, using carbon monoxide tracer, gas analyzers, and a data acquisition system, was applied to study the ventilation air distribution and the tracer removal efficiency, so-called pollutant removal efficiency, in the model room. The experiment was composed of two parts; firstly the AER was varied to examine its effect on the ventilation air distribution and the ventilation effectiveness and secondly both AER and CSL were considered to determine their effect on the pollutant removal efficiency. It was found that the ventilation effectiveness in the model was proportional to AER but not linearly. It was also found that changing the CSL can improve the pollutant removal efficiency. In some cases, the efficiency improvement by increasing AER was achieved by simply changing CSL.

  • PDF

HACCP의 환경 최적화를 위한 식품 클린룸 설계에 관한 연구

  • Won, Yeong-Jae
    • Air Cleaning Technology
    • /
    • v.23 no.3
    • /
    • pp.1-9
    • /
    • 2010
  • This study proposed the optimum design values for the biological clean room system observing the regulations of Hazard Analysis Critical Control Point (HACCP). Even though the standard for industrial clean room system has been well established, the basis for biological food clean room system is the first stage. In order to prevent the contaminations in advance for food storages, processes, and distributions, the criterion of Hazard Analysis Critical Control Point is positively required. This study also suggested the possible ways of how to avoid the hazardous contaminations.

  • PDF

On the Characteristics of the Flow with Opening and Shutting of Access Panels in a Clean Room (Access Panel 개폐에 따른 청정실내 유동특성)

  • Park, M.S.;Lee, Jae-Heon;Ahn, K.H.;Kim, J.H.
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
    • /
    • v.5 no.1
    • /
    • pp.55-64
    • /
    • 1993
  • A numerical investigation has been carried out for the two-dimensional flow and pressure characteristics in a clean room equipped with two kinds of filters and four access panels. The distributed pressure resistance concept was applied to describe the momentum loss in filters and access panels. As a result, the velocity profile in the clean room became rather smooth by the presence of access panels. Furthermore, the average pressure drop of each access panel reached the same value so that the ratio of the flow rate should be the same at any zone. The closing of an access panel with maintaining the other access panels being opened had influenced on the velocity distribution in lower two thirds of left half space of the clean room.

  • PDF

Simulation of the hot water ONDOL heating system by response factor method (應答係數法에 의한 溫水 溫室 暖房 시스템의 Simulation)

  • 조상준;민만기;최영돈
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.11 no.3
    • /
    • pp.409-424
    • /
    • 1987
  • Simulation on the hot water ONDOL heating system was made in order to investigate the variation of room temperature and specific fuel consumption of boiler. Heat balance equation was derived by response factors and solved implicitly. Variation of room temperature and specific fuel consumption of boiler were calculated with respect to the thickness of room floor, the absorptivity of wall for solar radiation, on-off temperature range of boiler and air exchange. The results show that specific fuel consumption of boiler is independent of the thickness of room floor and decreases with increasing the absorptivity of wall and on-off temperature range of boiler. However, it increases with increasing the air exchange. They also show that, when the absorptivity and on-off temperature range of boiler are increased, the amplitudes of room temperature variation increase.

Evaluation of Indoor Thermal Environment and Thermal Sensation in Traditional Ondol Room (전통온돌방의 실내온열환경 및 온열감에 관한 연구)

  • 김난행;손장열
    • Journal of the Korean housing association
    • /
    • v.15 no.2
    • /
    • pp.19-25
    • /
    • 2004
  • The aim of the research was to evaluate the characteristics of indoor thermal environment and thermal sensation in the traditional Ondol room. Indoor thermal factors including air temperature, operative temperature, floor surface temperature, relative humidity, PMV, OT were measured, and survey was carried out to understand subjective responses of resident's related to indoor thermal environment in Ondol room. The analysed houses are: the Chung hyo dang(the head house of Ryu family in Andong) and the Pyeung won jung(the traditional house in Yesan). The purpose of the survey was to know the relationship between resident's sensation and thermal environmental indicators such as air temperature, relative humidity, floor surface temperature, OT. The experimental results have pointed out how Ondol room may lead to comfortable and uniform indoor thermal environments.

Analysis on ventilation efficiency by CFD simulation for breathing zone in bed room (CFD해석에 의한 침실 호흡역의 환기효율 분석)

  • Yoo, Bok-Hee;Yoon, Chung-Sook
    • KIEAE Journal
    • /
    • v.2 no.3
    • /
    • pp.11-16
    • /
    • 2002
  • Indoor air environment is one of the most important factors that affect resident's health and comfort level. In this paper, the influence of ventilation efficiency with different types of furniture arrangement at breathing zone in a room was analyzed by numerical simulation based on computational fluid dynamics(CFD). The furniture layout of students' bedroom have been classified by three different patterns so that SVE3(scale for ventilation efficiency3) in the rooms was analyzed for air flow distribution. According to the results of the study, SVE3 has the maximum value in spaces between furnitures and each comer of the room. The furniture arrangement influences the ventilation efficiency. It was con finned that ventilation effective in a room is not uniformly distributed as compared the breathing zone with all the area in a room. It means that a study of ventilation efficiency was considered relatively with target zone(a residential or breathing zone) and all the area in a space.

Effectiveness of Ventilation Control in a Dry Room with a Heat and Moisture Source

  • Lee, Kwan-Soo;Lim, Kwang-Ok;Ahn, Kang-Ho;Jung, Young-Sick
    • International Journal of Air-Conditioning and Refrigeration
    • /
    • v.9 no.4
    • /
    • pp.1-9
    • /
    • 2001
  • The temperature and moisture distributions in a dry room with a heat and moisture source -i.e., workers- are studied numerically by using a standard $k-\varepsilon$ turbulence model. In order to evaluate the effectiveness of heat and moisture ventilation inside the room, the heat removal capacity and the moisture exhaust efficiency are introduced. The effectiveness of ventilation control is analyzed by evaluating the temperature and humidity distributions in the room quantitatively. It is found that the mean absolute humidity inside the room is almost constant regardless of the models and the heat generation rates in this study range. This results from the fact that the moisture generation by the workers was relatively small. Through the modification of the design, 40% improvement in critical decay time was achieved.

  • PDF

A Comparative Analysis on Cooling Energy of Heat Recovery Ventilator and Air Handling Unit in the Office Building (사무용 건물에서 전열교환 환기시스템과 일반공조기의 냉방에너지 비교분석에 관한 연구)

  • Jang, Ji-Hoon;Kim, Hyeonsoo;Auh, Jin-Sun;Leigh, Seung-Bok;Kim, Byungseon-Sean
    • KIEAE Journal
    • /
    • v.16 no.6
    • /
    • pp.123-128
    • /
    • 2016
  • Purpose: In order to save the energy consumption of buildings, buildings have been constructed with high performance insulation or airtightness. However, high performance insulation or air tightness has led to a poor indoor air quality. Therefore, HRV(Heat Recovery Ventilator) has received attention to save the energy consumption and insure a good air quality. Because existing research is almost about the performance of HRV in residential buildings, This study analyzed the effect of HRV on cooling energy consumption in commercial office building. Method: This study was proceeded at commercial office building in In-cheon. In order to evaluate the energy consumption of HRV, this study proposed two methods: estimating energy consumption of the room installed AHU(Air Handling Unit) system; estimating energy consumption of the room installed HRV system. Therefore, comparison of two methods was proceeded to evaluate energy performance of each method. Result: As the result of comparison between rooms installed AHU and HRV, the experiment showed that energy consumption of the room installed HRV system is about 22% less than the room of AHU system. This conclusion is considered because the room installed HRV system have maintained temperature well at set point temperature $26^{\circ}C$.

Indoor environmental alarm robot (실내환경 오염 측정장치 알람봇 구현)

  • Cho, Hae-Jin;Lee, Hye-bin;Lee, Gi-Ho;Oh, Min-u;Choi, Ji-Seung;Kim, Su-Min;Kim, Seong-Hyeon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2016.10a
    • /
    • pp.549-551
    • /
    • 2016
  • In this paper, With the development of modern science and technology are Sheds to stay indoors rather than outdoors space it increased significantly compared to the past. And a wide variety of research about outdoor air quality until recently, efforts are underway but the issue of air quality in the room is the fact that all considered relatively lightly. As the contamination of the room air is polluted, unlike the natural environment, a large outdoor air dilution rate, the dilution rate is very low, once the contaminated air continuously circulating exerts a very bad influence on the health of people staying in the room. In this study, movement characteristics of the person living in a room, the air measuring device for the study of the active indoor environmental control system reflects the life form to measure the quality of the measured air in real time for transmitting the information to the user of the smart devices, alarm bot It was implemented and operational applications.

  • PDF

The Mycobiota of Air Inside and Outside the Meju Fermentation Room and the Origin of Meju Fungi

  • Kim, Dae-Ho;Kim, Sun-Hwa;Kwon, Soon-wo;Lee, Jong-Kyu;Hong, Seung-Beom
    • Mycobiology
    • /
    • v.43 no.3
    • /
    • pp.258-265
    • /
    • 2015
  • The fungi on Meju are known to play an important role as degrader of macromolecule of soybeans. In order to elucidate the origin of fungi on traditional Meju, mycobiota of the air both inside and outside traditional Meju fermentation rooms was examined. From 11 samples of air collected from inside and outside of 7 Meju fermentation rooms, 37 genera and 90 species of fungi were identified. In outside air of the fermentation room, Cladosporium sp. and Cladosporium cladosporioides were the dominant species, followed by Cladosporium tenuissimum, Eurotium sp., Phoma sp., Sistotrema brinkmannii, Alternaria sp., Aspergillus fumigatus, Schizophyllum commune, and Penicillium glabrum. In inside air of the fermentation room, Cladosporium sp., Aspergillus oryzae, Penicillium chrysogenum, Asp. nidulans, Aspergillus sp., Cla. cladosporioides, Eurotium sp., Penicillium sp., Cla. tenuissimum, Asp. niger, Eur. herbariorum, Asp. sydowii, and Eur. repens were collected with high frequency. The concentrations of the genera Aspergillus, Eurotium, and Penicillium were significantly higher in inside air than outside air. From this result and those of previous reports, the origin of fungi present on Meju was inferred. Of the dominant fungal species present on Meju, Lichtheimia ramosa, Mucor circinelloides, Mucor racemosus, and Scopulariopsis brevicaulis are thought to be originated from outside air, because these species are not or are rarely isolated from rice straw and soybean; however, they were detected outside air of fermentation room and are species commonly found in indoor environments. However, Asp. oryzae, Pen. polonicum, Eur. repens, Pen. solitum, and Eur. chevalieri, which are frequently found on Meju, are common in rice straw and could be transferred from rice straw to Meju. The fungi grow and produce abundant spores during Meju fermentation, and after the spores accumulate in the air of fermentation room, they could influence mycobiota of Meju fermentation in the following year. This could explain why concentrations of the genera Aspergillus, Eurotium, and Penicillium are much higher inside than outside of the fermentation rooms.