• Title, Summary, Keyword: 굴뚝효과

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Influence of Stack Effect in High-Rise Buildings on Wind Effect in Jeju (Comparative Analysis of Seoul and Jeju) (제주지역 고층건축물에서의 바람의 영향이 굴뚝효과에 미치는 영향 분석 (서울과 제주지역간의 비교 분석))

  • Lim, Chae-Hyun
    • Fire Science and Engineering
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    • v.29 no.6
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    • pp.6-12
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    • 2015
  • This study used CONTAM modeling to analyzed analyze the stack effect in high-rise buildings for the terrain and weather conditions of Seoul and Jeju. The differential pressure caused by the stack effect is a function of the indoor and outdoor temperature difference and the height of the vertical shaft. Jeju is considered more stable than Seoul, because it is warmer than Seoul in winter. The differential pressure in Jeju is about 60% that of Seoul in for the same height of buildings in winter. However, Jeju is an island and the neutral plane is raised by over 56% by strong winds, although there is less differential pressure caused by the stack effect in Jeju than in Seoul. Due to the raised neutral plane, the region and magnitude of negative pressure in the lower part is larger in Jeju than in Seoul.

Study of exhaust stack degin for effective diffusion of atmospheric pollutant (대기오염물질의 효과적인 확산을 위한 굴뚝 설계에 관한 연구)

  • 김종철;김태형
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • pp.250-251
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    • 1999
  • 미국 산업환기 매뉴얼에서 빗물을 가장 효과적으로 방지하는 굴뚝으로 권장하고 있는 이중 굴뚝(Vertical Discharge Stack)을 우리의 기상조건에서 검증하여 그 사용가능성을 검토하고 기존에 우리 나라에서 가장 많이 사용되고 있는 삿갓모양과 "ㄱ" 모양 굴뚝의 불합리성을 지적할 뿐만 아니라 아울러 빗물 유입 방지나 배기저항을 최소화하고 배기확산에도 효과적인 새로운 모양의 굴뚝을 연구해 보고자 한다. (Clarke, J. H, 1965 ; Hama, G. M., 1963 ; ACGIH, 1998)(중략)

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Influence of the Entrance and Exit Lengths on the Natural Convection Heat Transfer of a Cylinder in a Duct (도관내 원형관의 자연대류 열전달에서 입구 및 출구 길이 효과)

  • Lim, Chul-Kyu;Chung, Bum-Jin
    • Journal of Energy Engineering
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    • v.21 no.1
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    • pp.18-25
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    • 2012
  • This work investigated the influence of the chimney dimensions(exit and entrance length, and diameter) on the heat transfer of a vertical cylinder in a duct. The measured mass transfer rates for the natural convection of vertical cylinder in a duct were presented for Prandlt number 2,094, Rayleigh number in the range of $4.55{\times}10^9$, $5.79{\times}10^{10}$, and $1.69{\times}10^{11}$. Experiments were performed using a copper sulfate electroplating system to simulate heat transfer based upon the analogy concept. The diameter of the duct was varied from 0.06 m to 0.14 m, and the heights from 0.30 m to 1.10 m. Nusselt numbers measured at open channel condition agreed well with the existing laminar heat transfer correlations for vertical plate developed by Le Fevre. The increase of the exit length enhanced the heat transfer up to a certain duct height but further increase does not affects the heat transfer. The heat transfer decreased with increasing the entrance length up to a certain duct height and was constant at further increase. The Nusselt number decreased with increasing the diameter of duct, until Nusselt number becomes similar to that at open channel beyond a certain diameter.

Design for Pressurizing System about Vestibule by Stack Effect & Engineering Analysis - Focused on Case Study - (굴뚝효과와 공학적분석에 의한 부속실 가압시스템 설계 - 사례를 중심으로 -)

  • Kim, Yong-Kwang
    • Fire Science and Engineering
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    • v.23 no.4
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    • pp.145-153
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    • 2009
  • We are generally applicate smoke control only vestibule about special escape staircase, it is one of some smoke control model of NFSC 501A. But there are some point at issue in this system. The smoke control system on supervision field of writer is smoke control only vestibule same as the other resemble field. Writer studied in the concrete to find a solution at this issue, and derived a conclusion the most reasonable system on the field is "same time smoke control for staircase and vestibule" by the engineering analysis considering stack effect.

A Numerical Analysis on the Indoor Air Ventilation by Stack Effect and Outdoor Wind in a High-rise Residential Building (초고층 주거건물에서 굴뚝효과와 외풍영향에 인한 실내 환기 기류해석 및 평가에 관한 연구)

  • Kim, Chi-Wan;Lim, Tae-Kun;Ahn, Young-Chull
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.23 no.12
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    • pp.828-835
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    • 2011
  • The purpose of this study is to analyze and evaluate the 3 types of indoor ventilation methods such as natural, mechanical, and hybrid ventilation in high-rise building which is affected by stack effect and outdoor air pressure. For the evaluation of the ventilation capacity, CFD simulation was performed in a typical high-rise residential building. The results of the simulations are as follows: 1) Natural ventilation method is not enough to the regulation. 2) In case of mechanical ventilation, congested area is occurred but meets the regulation. 3) In case of hybrid ventilation with stack effect, all the areas of indoor meet the regulation and congested area is reduced. 4) In case of high-rise building, the differences of ventilation rate among houses in the building are not large because the mechanical ventilation is main factor.

피동형 격납건물 냉각계통 내 돔 효과의 수치적 해석에 관한 연구

  • 전지한;박홍준;이은철
    • Proceedings of the Korean Nuclear Society Conference
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    • pp.298-303
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    • 1997
  • 실제의 격납건물의 구조는 하부 원통형의 구조를 가지는 영역과 상부 돔 형태와 굴뚝 형태의 구조를 가지는 영역으로 나눌 수 있다. 하부 원통형의 구조만을 고려한다면, 고온의 철제 벽면과 콘크리트 벽면 사이의 gap 크기에 비해서 원통의 반지름이 상대적으로 매우 큰 값을 가지기 때문에 2차원 무한평판으로 가정하는 것이 가능하다. 그러나 돔 및 굴뚝 영역에서는 높이가 높아질수록 돔 단면직경이 감소하고 굴뚝 영역도 유동단면적이 작은 원통의 구조를 가져 2차원 무한평판의 가정에 많은 무리가 따른다. 앞에서 명시한 세 가지의 격납건물 형태에 있어서 ASPWR의 경우는 굴뚝을 포함한 영역까지도 무한평판으로 가정하는 것이 가능하나(돔에서의 열전달 단면적이 하부의 열전달 단면적에 비해 매우 작다는 가정을 한다면) 나머지 AP600과 HWRF의 격납건물에 있어서는 상부까지도 무한평판 가정을 사용하는 것에는 무리가 있다. 본 연구에서는 일반적인 유체해석 코드인 FLUENT V4.3을 이용하여 실제 격납건물 구조에 대한 분석을 시도하여 무한평판 구조에 대한 가정이 과도한 열전달량을 예측하고 있음을 확인하였다.

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Basic Study on the Proportional Control System Development of Air Supply Damper (급기댐퍼의 비례제어시스템 개발에 관한 기초 연구)

  • Lee, Dong-Myung;Yu, Byung-Ku
    • Proceedings of the Korea Institute of Fire Science and Engineering Conference
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    • pp.97-100
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    • 2012
  • 본 연구는 비례제어시스템의 개발에 관한 기초 연구로서 건축물 화재에서 연기이동의 원인이 되는 압력수두손실, 굴뚝효과, 바람의 영향 등과 피난시 과압방지를 효율적으로 제어하여 제연구역에 균일한 허용차압을 유지시킬 수 있는 제연구역 급기댐퍼의 비례제어시스템을 개발하여 화재실로부터 발생된 연기가 다른 공간으로 침입 확산되는 것을 방지하고 피난안전성을 확보하여 인명과 재산피해를 최소화하는 것이며, 비례제어시스템의 로직 정립과 공학 해석에 의한 시스템 설계에 관한 것이다.

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An Experimental Study of Critical Velocity in Sloping Tunnel Fires (경사 터널내 화재시 임계속도에 관한 실험적 연구)

  • 이성룡;김충익;유홍선;김혁순;전명배
    • Fire Science and Engineering
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    • v.18 no.1
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    • pp.49-53
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    • 2004
  • In this study, reduced-scale experiments were conducted to analyze an effect of tunnel slope on critical velocity. The 1/20 scale experiments were carried out under the Froude scaling using ethanol pool fire. Square pools ranging from 2.47 to 12.30㎾ were used experiments. Critical velocity varied with one-fourth power of the heat release rate. As the slope of the tunnel increases the critical velocity comes to be fast due to the increase of the chimney effect.

Experimental Study on Airtightness Performance of the House with High Levels of Insulation and Airtight Construction (고기밀 고단열 주택의 기밀성능에 관한 실험적 연구)

  • Shin, U-Cheul;Yoon, Jong-Ho;Baek, Nam-Choon
    • Journal of the Korean Solar Energy Society
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    • v.25 no.4
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    • pp.61-67
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    • 2005
  • The purpose of this study is to evaluate the air tightness of Zero Energy Solar House(ZeSH) and to propose the construction improvement of junctions and penetrations where air infiltration was identified. Air leakage rate were measured by means of blower door test in accordance with ASTM E779-87. The results showed that ZeSH has an excellent airtightness with ACH50/20 (air change per hour at a pressure difference of 50 Pa between inside outside) of 0.34hr-1 and leakage class E by normalized leakage area of ASHRAE.

A case study for prediction of the natural ventilation force in a local long vehicle tunnel (장대도로터널의 자연환기력 예측 사례연구)

  • Lee, Chang-Woo;Kim, Sang-Hyun;Gil, Se-Won;Cho, Woo-Chul
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.11 no.4
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    • pp.395-401
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    • 2009
  • One of the key design factors for the ventilation and safety system at extra long tunnel is the airflow velocity induced by the natural ventilation force. Despite of the importance, it has not been widely studied due to the complicated influencing variables and the relationship among them is difficult to quantify. At this moment none of the countries in the world defines its specific value on verified ground. It is also the case in Korea. The recent worldwide disasters by tunnel fires and demands for better air quality inside tunnel by users require the optimization of the tunnel ventilation system. This indicates why the natural ventilation force is necessary to be thoroughly studied. This paper aims at predicting the natural ventilation force at a 11 km-long tunnel which is in the stage of detailed design and will be the longest vehicle tunnel in Korea. The concept of barometric barrier which can provide the maximum possible natural ventilation force generated by the topographic effect on the external wind is applied to estimate the effect of wind pressure and the chimney effect caused by the in and outside temperature difference is also analyzed.

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