• 한국방재학회:학술대회논문집
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• 한국방재학회 2007년도 정기총회 및 학술발표대회
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• pp.242-245
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• 2007

초고층건물의 주된 피난경로인 계단실에 발생하는 연돌효과는 계단실 차압분포에 큰 영향을 주고 피난에 장애가 될 수도 있으므로 적정 범위 내에서 억제되어야한다. 고층건물의 연돌효과를 해소하는 방법을 찾기 위해 몇 가지 경우에 대해 시뮬레이션을 하고 계단실 상하부의 fan으로 가압과 감압을 적절히 병용한 결과 연돌효과에 의한 차압불균형을 해소할 수 있었다.

• Journal of Mechanical Science and Technology
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• 제20권3호
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• pp.391-398
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• 2006

This work involves a method for modeling the flow distribution in the stack of a solid oxide fuel cell. Towards this end, a three dimensional modeling of the flow through a Solid Oxide Fuel Cell (SOFC) stack was carried out using the CFD analysis. This paper examines the efficacy of using cold flow analysis to describe the flow through a SOFC stack. It brings out the relative importance of temperature effect and the mass transfer effect on the SOFC manifold design. Another feature of this study is to utilize statistical tools to ascertain the extent of uniform flow through a stack. The results showed that the cold flow analysis of flow through SOFC might not lead to correct manifold designs. The results of the numerical calculations also indicated that the mass transfer across membrane was essential to correctly describe the cathode flow, while only temperature effects were sufficient to describe the anode flow in a SOFC.

• 한국건축시공학회지
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• 제21권5호
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• pp.483-493
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• 2021

도시 인구의 과밀화로 고층 건물에 대한 폭발적인 수요와 공급이 발생하였다. 고층 빌딩은 각 도시의 구심점으로 도시 이미지를 제고하는데 기여하고 있으나 연돌효과로 인해 승강기 문의 오작동, 외벽의 문과 창문 개폐의 어려움, 상층부로 확산하는 연기와 악취, 소음, 에너지 손실, 화재 및 오염물질의 급속한 확산 등 예기치 못한 다양한 문제를 야기하고 있다. 본 연구에서는 초고층 건축물을 수직조닝별로 구분하여 연돌효과의 원인과 해결방안을 분석하고 설계와 시공 방안으로 도출하였다. 외기를 차단하는 초기 계획과 정밀한 시공을 통한 기밀성 확보를 통해 저층부에서 유입되는 기류를 능동적으로 차단하여 건물의 내·외부 기밀성을 확보하는 방안을 모색하였다. 설비적 해결대책은 연돌효과로 인한 특정 현상을 줄이기 위한 대책이 될 수 있으나 이에 따른 2차 피해의 가능성이 높기 때문에 최소한으로 적용해야 한다. 따라서 본 연구는 연돌효과의 원인과 대책방안을 수직 조닝별로 설계적, 시공적 대책을 제시함으로써 체계적인 연돌효과 관리의 필요성을 역설하였다. 또한 본 연구가 설계 및 시공뿐만 아니라 건물 유지관리에도 도움이 되기를 기대한다.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2010년도 춘계학술논문발표회 논문집
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• pp.284-288
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• 2010

건물 높이에 비례하여 피난계단의 길이가 증가하면서 피난 인원부하도 함께 늘어나기 때문에 피난시간은 건물 높이에 제곱비례하는 것으로 볼 수 있다. 연기의 수직전파가 신속한데 비하여 피난 속도는 너무나 늦기 때문에 수직피난로의 안전을 위한 대책이 절실하다. 현존하는 수직피난경로의 급기가압식 제연시스템은 흑한기에 연돌효과에 의해 기능이 현저히 제한을 받게 된다. 이러한 문제를 해결하기 위해 계단실을 외부로 개방하거나 계단실과 외부 사이의 공기 소통을 자유롭게 함으로써 혹한기 연돌효과를 극복할 수 있다.

• 설비공학논문집
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• 제16권9호
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• pp.796-803
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• 2004

The stack effect of a new type condenser installed in a high-rise apartment building was studied numerically A sirocco fan is introduced to the new type condenser instead of an axial flow In. The new type condenser intakes the cold air through the lower inlet and exhausts the hot air through the upper outlet. The effects of the building height and frontal wind on the performance of an air-conditioner were analyzed. The performance of an air-conditioner was evaluated by using COP (coefficient of performance) and CGPI (condenser group performance indicator). the hot air was exhausted by the new type condenser at an angle of 50$^{\circ}$ from the outer wall of the building. If there was no draft, the new type condenser installed in the high-rise apartment building had a good performance and its performance on each floor is not influenced by the stack effect. It is shown that the efficiency of the air-conditioner installed in several floors below the top floor decreased when the frontal wind velocity was greater than 8 m/s.

• 설비공학논문집
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• 제23권12호
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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.

• 한국화재소방학회논문지
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• 제23권6호
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• pp.82-90
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• 2009

본 연구에서는 화재 시 효과적인 연기배출을 위해 국내 건축법에서 규정하고 있는 배연창이 고층건물의 연돌효과 및 배연성능에 미치는 영향을 분석하기 위해 현장실험과 모델링 해석을 병행하였다. 현장실험은 배연창이 설치된 고층건물을 대상으로 정상조건 및 배연창 개방조건에서 외기온도에 따른 계단실, 부속실 및 복도에서의 압력분포 측정을 통해 연돌효과를 분석하였다. 모델링 해석에서는 연기유동 해석용 네트워크모델인 CONTAMW을 이용하여 모델링결과 및 실험결과의 비교분석을 통한 보정기밀도를 적용하여 이상적인 대상건물을 구현하고 배연창의 배연성능을 평가하였다.

• 대한안전경영과학회지
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• 제26권1호
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• pp.15-24
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• 2024

The purpose of this study is to improve the stack effect of the staircase and the failure to take into account the opening of the outside door of the staircase, which are the disadvantages of the existing smoke control only vestibule. As a result of the study, the new vestibule and the staircase simultaneous smoke control are equipped with an exhaust flap damper with an effective opening area of about 0.25 m² in the upper part of the staircase, and a ventilator-type air supply fan of about 5 m³/s in the lower part, and take measures to prevent overpressure in the staircase. If you use the new simultaneous smoke control method of the vestibule and staircase, you can achieve the following effects. First, it is possible to open the external entrance door. Second, it can reduce the stack effect. Third, the staircase door closes automatically without fail. And a new method of preventing overpressure was proposed for the vestibule.

• 한국전기전자재료학회논문지
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• 제16권1호
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• pp.77-82
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• 2003

The ac loss is an important issue in the design of high-Tc superconducting power devices such as transformers and cables. In these devices many Bi-2223 tapes are closely stacked together and exposed to alternating magnetic fields that can have different orientations with respect to a tape. In such arrangement the magnetization loss is influenced by the screening current induced in adjacent tapes and thus different from that in a single tape. This stacking effect was experimentally investigated by measuring the magnetization loss in a stack, which consists of a number of tapes. First the magnetization loss in the single tape was measured in order to confirm the reliability of the loss data measured in the stack. The results for the single tape coincide well will the loss characteristics described in other previous works. For the stack In parallel and longitudinal magnetic fields the measured loss is Independent of both the number of tapes and stacking type. The longitudinal magnetization loss Is well explained rather by the slab model for decoupled filaments. For the tall stack in perpendicular field the measured loss at low fields is greatly decreased, compared to the loss of the single tape. However the loss at high fields is unaffected. These loss behaviors in the tall stack are well described by the slab model for full coupling.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.889-894
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• 2008

Exhaust system used in toilet and cooking place of high riser public house is roof fan of two basic types : natural roof ventilator and natural/forced roof ventilator. Natural/forced roof ventilator has a motor in the rotary shaft. There are many high riser public house in Korea. These buildings were not viewed as being major contributors to exhaust pollutants producted in indoor. It was because many engineers thought that exhaust in high riser building depend on stack effect. This study investigates on stack pressure determined by exterior pressure and the difference pressure control in exhaust stack used in high riser public house. This paper focuses mainly on the effect of the time interval for power supply of motor installed in roof fan with function of natural wind velocity and of exhaust air volume of toilet. It is observed there are higher exhaust efficiency than the existing natural roof ventilator.