• Title/Summary/Keyword: Smoke particles

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A Numerical Simulation of Smoke Control in Daegu Subway Stations I. Smoke Control System (대구 지하철역 제연의 문제점과 대책 I. 제연방식)

    • Fire Science and Engineering
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    • v.17 no.4
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    • pp.98-104
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    • 2003
  • Smoke control in il space 10 m${\times}$3 m floor and 5.4 m high around the stairway of a subway station platform was simulated by using FDS to investigate problems of smoke control in Daegue subway stations. Distributions of temperature and smoke particles, and variation of the number of particles with time for a 200 ㎾ polyurethane fire were compared. It was shown that the purge system fails to remove smoke efficiently and that the extraction system has the highest perfor-mance among the three smoke control systems for the given situations. Simply switching the purge system into extraction mode might improve much the smoke removal performance.

Development of Packed Bed Lung Model for the Deposition Studies of Fire Smoke (흡입연기의 침착 실험을 위한 충전층 폐모델 개발에 관한 연구)

  • Goo, Jae-Hark
    • Fire Science and Engineering
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    • v.22 no.2
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    • pp.121-128
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    • 2008
  • Adverse health effects of inhaled smokes are associated with the amount of the particles deposited in human lung. Lung model is needed to simulate smoke deposition because of the hardness of the in vivo deposition experiment. However, it is hard to realize the successively decreasing bifurcations in the model. In this work, an experimental lung model was developed to simulate the smoke deposition in the lung. Instead of bifurcating airways, the lung model was made of packed beds of which size decreased downwards. The experimental results using this model showed good agreements with existing results for real lung in the deposition characteristics. The model could be applied to the studies of health risk assessment of the inhaled smoke particles generated by fire.

Optical Properties for Smoke Particles of Fire Sources According to UL 268 (UL 268 화원에 의한 연기입자의 광학적 특성)

  • Jee, Seung-Wook;Lee, Jong-Hwa
    • Fire Science and Engineering
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    • v.28 no.2
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    • pp.9-13
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    • 2014
  • This paper is basic study for development of the photoelectric-type smoke detector that is able to distinguish fire source as well as fire detection. For this subject, Light source and sensor which is normally used for the conventional smoke detector are assembled for the optical chamber. Using 3 type of the test fires (the paper fire, the wood fire, the flammable liquid fire) this paper attempts to find optical properties of each fire. These 3 type of fire are used in the testing of smoke detector according to UL 268 standard. As the result, there are disambiguated between the paper fire and the wood fire in scattering and reason of extinction in the flammable liquid fire is different from that of the paper and the wood fire.

A Study on the Oil-mist/Smoke Collecting Module for the Pure Energy Recycling (청정에너지 회수용 유증기/매연 포집모듈에 관한 연구)

  • Kim, Myung-Soo;Ohkura, Shigenobu;Ham, Koung-Chun
    • 한국태양에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.279-284
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    • 2009
  • Traditionally, so-called "industrial waste gases", such ad exhaust from boilers at industrial installations and a large quantity of soot discharged from power station, before their release into the atmosphere, have been on occasion subjected to an air cleaning process to remove fine particles that may pollute the atmosphere (such as mist and dust containing various powdery or oily substances and moisture from industrial waste gases). The release of industrial waste gases containing these particles directly into the atmosphere poses a serious threat to the earth environment; and recovery of these noxious substances is required by law in some countries and local governments. in urban areas, air pollution from automobile exhaust and others creates a serious condition. Some homes are equipped with and use indoor air purifiers. In many of the kitchens of restaurants, smoke generated during cooking and otherwise contaminated air are cleansed by air purifiers before being released outside or recycled inside. For the dust collecting devices to recover the fine particles contained in contaminated air, the cause for air pollution and how to purify air, many types based on various principles are known. Specifically, classified based on theories of particle collection, filtration, gravity, inertia, centrifugation, electricity, and cleaning types are cited as available processes. Among them, an appropriate type is selected according to the size or type of fine particles to be collected and conditions for installation. For the efficiency of dust collection, a filtration system (by using bag filters and others) and electric system are particularly outstanding and are therefore used widely in various areas of industry. In this research, rotary type high performance oil mist and smoke collecting system with self auto cleaning device equipped with the cleaning fluid spraying section is investigated.

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An Experimental Study on the Removal Characteristics of Indoor Air Pollutants using an Air Cleaning System (실내 공기정화 시스템에 의한 실내 오염입자의 제거특성에 관한 실험적 연구)

  • 김성찬;이창건;안영철;이재근;강태욱;이감규;구정환
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.15 no.9
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    • pp.733-737
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    • 2003
  • The purpose of this study is to analyze the particle removal characteristics of a commercial air cleaner based on the electrostatic precipitator. The air cleaner consists of a positive corona precharger to precharge particles and a collector to remove the charged particles. The test for particle removal efficiency is conducted with tobacco smoke particles of 1.27${\mu}{\textrm}{m}$ in mass median diameter. The result of one-pass filtration test shows that the filtration efficiency is more than 90% for the particles larger than 2.5 Um, while the efficiency for the particles of 0.5~1.0${\mu}{\textrm}{m}$ in case of 4.18 CMM is 70%. For the test room of 5,800${\times}$3,400${\times}$2,600㎣, the concentration of tobacco smoke particles decreases up to 30% of initial values within 30 minutes due to natural reduction and up to 90% of initial values within 30 minutes with the air cleaner operation.

Development of a precision smoke particle detector to sense a fire in early state (초기화재 감지를 위한 정밀한 연기 입자 감지 장치 개발)

  • 김희식;김영재;이호재
    • 제어로봇시스템학회:학술대회논문집
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    • 1997.10a
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    • pp.1734-1737
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    • 1997
  • The conventional fire detection devices are operated after a processed fire phase, which are sensing only a high density of somke level or high temperature heat. They are not so precision to detect a fire in the early phase to protect the facility form the fire. We need to develope a new high precision smoke detection system to keep expensive industrial facilities most reliably form fire. A new optical precision smoke detection system was developed. It monitors very low level density of smoke particles in the air. It is operated continously through many years without a stop or any malfunction. The developed precision smoke detection system will be installed in important industrial facilities, such as power plants, underground common tunnel, main control rooms, computer rooms etc.

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Characterization of Respirable Suspended Particles and Polycyclic Aromatic Hydrocarbons associated with Environmental Tobacco Smoke

  • Baek, Sung-Ok;Park, Jin-Soo;Kim, Mi-Hyun;Roger A, Jenkins
    • Journal of Korean Society for Atmospheric Environment
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    • v.16 no.E
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    • pp.1-17
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    • 2000
  • In this study, the concentrations of particulate organic constituents of environmental tobacco smoke(ETS) were determined using an environmental smog chamber, where ETS is the sole source of target compounds. ETS was generated in a 30 ㎥ environmental chamber by a number of different cigarettes, including the Kentucky 1R4F reference cigarette and eight commercial brands. A total of 12 experimental runs was conducted, and target analytes included a group of ETS markers both in vapor and particulate phase and a class of polycylic aromatic hydrocarbos(PAHs) associated with ETS particles. The mass concentrations of PAH in ETS particles were also determined. The average contents of benzo(a) pyrene and benzo(a) anthracene in ETS particles for the commercial brands were 12.8 and 21.5$\mu\textrm{g}$/g, respectively, There values are all somewhat higher than those determined previously by other studies. Results form the chamber study are further used to estimate the average and variability of cigarette yields for target compounds associated with ETS. Finally, ratios of RSP to the surrogate standards of UVPM, FPM and solanesol were calculated for each sample. The average conversion factors factors for the eight commercial brands were 7.3, 38, and 41 for UVPM, EPM, and solanesol, respectively. The UVPM and FPM factors are in good agreement with the recently published values. Whereas there might be a substantial difference in the solanesol content among cigarettes produced in different countries, the variability is somewhat greater than those of UVPM and FPM, Unfortunately, comparison of the PAH yield data from this study with literature values was complicated by a lack of consistency in cigarette smoke generating methodology. Validation of the PAH yields was also difficult due to a lack of information on the ETS related PAH in the literature. From and engineering viewpoint , however, these data on the cigarette yields of ETS components may still provide useful information to studies on the mathematical modeling of indoor air quality management regarding tobacco smoke as a source of interest, or to studies on the assessment of human exposure to ETS.

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Analysis of the Response Time of a Photoelectric Spot-Type Smoke Detector Depending on the Type of Fires (화원에 따른 광전식 연기감지기 반응시간 분석)

  • Jee, Seung-Wook
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.27 no.5
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    • pp.89-94
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    • 2013
  • The fire testing performed for smoke detector model approval in Korea tests only one kind of fire smoke. A photoelectric spot-type smoke detector using Mie scattering is affected by the wavelength of light beam and the particle diameter. According to UL (Underwriters Laboratories Inc.) 268 standard, this paper analyze the characteristic of the response for a photoelectric spot-type smoke detector on sale in Korea using various fire smokes. Probability that the response time is included in non-defective range is 100% in paper fire, 90% in wood fire and 75% in flammable liquid fire, 90% in wood fire and 75% in flammable liquid fire. According to the estimation for population mean of the response time choosing a confidence level of 99%, a maximum of 19% for wood fire and that of 38% for flammable liquid fire are defective. As the result of analysis of smoke particle, this paper is found that these results are caused by the smoke particles are wide variations in size or have very black.

Characterization of Particle Size Distribution of Infiltrated Secondhand Smoke through the Gap in a Single Glazed and a Secondary Glazed Window by Indoor and Outdoor Pressure Differences (실내외 압력 차에 따른 단창과 이중창의 틈새로 침투된 간접흡연의 입자 크기 분포 특성)

  • Kim, Jeonghoon;Lee, Kiyoung
    • Journal of Environmental Health Sciences
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    • v.44 no.4
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    • pp.360-369
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    • 2018
  • Objectives: Outdoor tobacco smoke can penetrate into the indoor environment through cracks in the building envelope. This study aimed to characterize the particle size distribution of infiltrated secondhand smoke (SHS) through the gap in a single glazed and a secondary glazed window according to pressure differences in a chamber. Methods: Two polyvinyl chloride sliding windows were evaluated for infiltration, one with a glazed window and the other with a secondary glazed window. Each window was mounted and sealed in a polycarbonate chamber. The air in the chamber was discharged to the outside to establish pressure differences in the chamber (${\Delta}P$). Outdoor smoking sources were simulated at a one-meter distance from the window side of the chamber. The particle size distribution of the infiltrated SHS was measured in the chamber using a portable aerosol spectrometer. The particle size distribution of SHS inside the chamber was normalized by the outdoor peak for fine particles. Results: The particle size distribution of SHS inside the chamber was similar regardless of window type and ${\Delta}P$. It peaked at $0.2-0.3{\mu}m$. Increases in particulate matter (PM) concentrations from SHS infiltration were higher with the glazed window than with the secondary glazed window. PM concentrations of less than $1{\mu}m$ increased as ${\Delta}P$ was increased inside the chamber. Conclusions: The majority of infiltrated SHS particles through window gap was $0.2-0.3{\mu}m$ in size. Outdoor SHS particles infiltrated more with a glazed window than with a secondary glazed window. Particle sizes of less than $1{\mu}m$ were associated with ${\Delta}P$. These findings can be a reference for further research on the measurement of infiltrated SHS in buildings.

Flow Field Analysis of Smoke in a Rectangular Tunnel

  • Lee, Yong-Ho;Park, Sang-Kyoo
    • Journal of Advanced Marine Engineering and Technology
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    • v.33 no.5
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    • pp.679-685
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    • 2009
  • In order to simulate a smoke or poisonous gas emergency in a rectangular tunnel and to investigate a better way to exhaust the smoke, the characteristics of smoke flow have been analyzed using flow field data acquired by Particle Image Velocimetry(PIV). Olive oil has been used as tracer particles with the kinematic viscosity of air, $1.51{\times}10^{-5}\;m^2/s$. The investigation has done in the range of Reynolds number of 1600 to 5333 due to the inlet velocities of 0.3 m/s to 1 m/s respectively. The average velocity vector and instantaneous kinematic energy fields with respect to the three different Reynolds numbers are comparatively discussed by the Flow Manager. In general, the smoke flow becomes more disorderly and turbulent with the increase of Reynolds number. Kinematic energy in the measured region increases with the increase of Reynolds number while decreasing at the leeward direction about the outlet region.