• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.235-236
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• 2022

In the present study, the effect of horizontal vent position on fire phenomena in the enclosure with vertical and horizontal vents was examined using numerical simulation. Case 1 indicates the condition that the horizontal vent is in the center of the ceiling. Case 3 indicates the condition that the horizontal vent is far away from the vertical vent. Case 2 indicates the condition that the horizontal vent is installed between Case 1 and Case 3. The temperature distribution, smoke layer temperature, velocity distribution, and mass flow rate of horizontal vent flow were analyzed. In Case 2, the temperatures were lowest and the mass flow rate through the horizontal vent was largest. This is because the flame is inclined by the inflow through the vertical vent. Hence, to determine the proper horizontal vent location for the high smoke ventilation performance, the inflow through the vertical vent and its effect on flame behavior should be considered.

• 한국화재소방학회논문지
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• 제22권4호
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• pp.1-10
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• 2008

본 연구에서는 미국 NFPA 204 기준에 의해 설계된 수직 배연구에 대하여 배연구의 위치, 외기 온도, 풍속 및 화재크기가 자연배연 성능에 미치는 영향과 화재특성을 CFAST 프로그램을 사용하여 수치 해석적으로 조사하였다. 배연구는 외벽의 최고 상부에 위치한 경우와 외기온도가 낮은 경우 및 풍속이 작은 경우 배연성능기준을 만족하였다. 또 화재크기가 클수록 배출량은 증가하나 연기층 높이는 낮아져 배연성능기준을 만족하지 못하였다. 직접 외기와 통하는 수직 자연배연구의 설계시 해당지역의 최고 온도와 최대 풍속을 고려하고, 설계화재를 정확히 결정하여 배연성능기준이 만족되도록 주의가 요망된다.

• 설비공학논문집
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• 제16권2호
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• pp.135-141
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• 2004

The present paper concerns a smoke movement in a tunnel fire with a vertical shaft. The model tunnel measured 13.4m long, 0.4m wide and 0.4m high. The cross section is 1： 20 of a full scale tunnel. Ethanol was used as a fuel. The fire size in model tests varied from 1.35 kW to 13.37 kW, which corresponds to full scale fires of 2.41 to 23.91 MW. Smoke front velocity and temperatrue were decreased due to the vertical shaft install. Temperature was reduced maximum about 2$0^{\circ}C$ at ceiling and about 23$^{\circ}C$ at vertical position. CO concentration was reduced as the vent width widened. When vent width was more than 15 cm, CO concentration was not reached 100 ppm. Descent degree of the smoke layer was confirmed through the visualization.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.970-975
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• 2008

This study considers indoor thermal comfort in an ondol space by supply vent configurations to prevent cold draft in winter. A specially-designed vent cap has been investigated in comparison with a round pan-type vent and a simple opening without a cap. Numerical simulations have been conducted using CFD to analyze thermal comfort indices such as Predicted Mean Vote (PMV) and Effective Draft Temperature (EDT) as well as air distribution index i.e. Air Diffusion Performance Index (ADPI). Results show the new vent cap provides improved thermal comfort conditions especially near ondol heated floor, as the cold outdoor air spreads upwards along the vertical wall before reaching occupant region near floor. This paper includes discussions on the flow and comfort distributions created by the thermal jets from the vents.

• 설비공학논문집
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• 제14권9호
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• pp.691-698
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• 2002

In this study, reduced-scale experiments were conducted to analyze smoke movement in tunnel fires according to vepntilation method. The 1/20 scale experiments were carried out under the Froude scaling using gasoline pool fires ranging from 6.6 to 10 cm in diameter corresponding to total heat release rate from 0.714 to 2.5 kW. Temperatures near the ceiling were lowered by installing the vent, and much lowered by operating fan compared wiht tile case without vent. In case of forced ventilation, the exhaust fan was more effective than the intake fan. Vertical temperatures at the upper part of the tunnel were also lowered by installing the vent. But, when suction fan was operated, temperatures at the lower part of the tunnel were higher than that without vent.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.491-496
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• 2009

Recently, the high-rise building has been constructed competitively because it is symbol of the national competitive power including the technical power. The higher buildings are getting, the more important building mechanical systems are. So, the building mechanical systems are getting developed. Among the building mechanical systems, the sanitary system is basically necessary in order to maintain the building hygienically along with convenience and safety. This study has been investigated for various cases of high-rise building plumbing system. As a result, a variety of zoning method has been applied to most skyscrapers depending on the building height in the building mechanical system. And a variety of joint have been applied to minimize the Shortening and Sway. Also, the drainage in same uses has been discharged outside of a build through the one vertical pipe line. And airing system has been used like Individual Vent Pipe Yoke Vent Pipe Stack Vent Pipe Loop Vent Pipe Relief Vent Pipe method. It is sure that this study could be used as the high-rise building design.

• 대한기계학회논문집B
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• 제32권1호
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• pp.1-6
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• 2008

In order to establish detailed plans for fire protection and reduce the possible fire accidents in the future, a study on the shock wave caused by VCE(Vapor Cloud Explosion) is very important. Destruction phenomena of structure by gas explosion is due to the explosion pressure and heat. Explosion pressure is a kind of energy converted from the gas mixture explosion. Therefore, the propagation progress of shock wave and flame is very important. This study investigated the shock wave caused by VCE in enclosure with opened vent port. From a result, the vent port of top at the straight line of ignition and leak location was opened most rapidly, and the vertical vent port not opened.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.54-59
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• 2007

In order to establish detailed plans for fire protection and reduce the possible fire accidents in the future, a study on the shock wave caused by VCE(Vapor Cloud Explosion) is very important. Destruction phenomena of structure by gas explosion is due to the explosion pressure and heat. Explosion pressure is a kind of energy converted from the gas mixture explosion. Therefore, the propagation progress of shock wave and flame is very important. This study investigated the shock wave caused by VCE in enclosure with opened vent port. From a result, the vent port of top at the straight line of ignition and leak location was opened most rapidly, and the vertical vent port not opened.

• 한국전산유체공학회지
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• 제17권4호
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• pp.49-55
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• 2012

Research has importance in proposing the design of a tunnel with a vertical vent to secure passengers in a comfortable environment and safe against pressure. Using several analysis methods, the magnitude of the pressure induced by the vertical vent in the tunnel can be analyzed. In addition to the 3-dimensional method, the 2-dimensional method and the 2-dimensional axis-symmetric method are also used to analyze the strong and weak points of each so that the optimum analysis method can be obtained. As a result, it appears that the 2-dimensional axis-symmetric method is the most suitable in analyzing tunnel pressure consider to accuracy and time effective aspect. Also, the 3-dimensional method is disadvantageous in that it takes longer in calculating results, but is more effective in predicting phenomena around the vertical vent in the tunnel.

• 한국산학기술학회논문지
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• 제20권4호
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• pp.619-625
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• 2019

저심도 터널에서는 온도차에 의한 부력을 이용한 자연배기시스템이 많이 사용되고 있지만 이는 연기배출을 인위적으로 조절할 수 없다. 그러므로 자연배기시스템에서는 수직환기구에서 연기 배출량이 설계된 연기 배출량보다 적어지는 Plug-holing 현상을 고려한 설계가 필수적이다. Plug-holing 현상은 터널과 수직환기구의 형상 위치, 화원의 위치와 발열량 등에 영향을 받는다. 본 연구에서는 터널과 자연 환기구의 단면적 비와 화원의 열방출률이 자연배기시스템에서 발생하는 Plug-holing 현상에 미치는 영향에 대하여 실험적으로 분석하였다. 1/20 크기로 축소시킨 실험모델에서 터널과 수직환기구의 종횡비는 고정시키고 터널과 수직환기구의 단면적 비를 달리하여 Plug-holing 현상에 미치는 영향을 확인하였다. 화원의 열방출율은 0.55 kW, 0.98 kW, 1.67 kW로 고정시켰다. 실험결과, 연기 경계층온도와 수직환기구 내의 온도와의 비교를 통한 Plug-holing 발생을 판단하였고, 터널과 수직환기구의 단면적 비가 증가함에 따라서 수직환기구 하부의 유동과 온도분포 특성이 변함을 확인하였다. 터널 화재 시 Plug-holing 현상은 터널과 수직환기구의 단면적 비에 영향을 받으며 단면적 비가 클수록 Plug-holing 발생 가능성이 증가하였다.