• 터널과지하공간
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• 제19권3호
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• pp.226-235
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• 2009

터널내 자연환기력은 터널의 정상운영시 뿐만 아니라 터널내 화재와 같은 비상시에 기류 유동상의 심각한 문제를 야기할 수 있다. 따라서 자연환기력의 영향은 터널 환기 및 방재시스템 설계시에 반드시 고려하여야한다. 자연환기력의 결정에 영향을 미치는 변수에는 지형, 기상, 터널의 물리적 특성에 관련된 다양 변수들이 포함된다. 그러나 이들 변수간의 정량적인 관계의 이해가 복잡하여 현재 어떤 나라에서도 국가기준에 자연환기력의 예측방법을 제시하고 있지 않다. 본 논문에서는 국내 고속도로터널을 대상으로 자연환기력의 정량화 연구를 수행하였다. 정량화를 위하여 첫째, 양 갱구의 기압차 측정방법, 둘째, 피스톤효과에 의한 영향을 제거하는 방법, 셋째, 기압장벽고 방법을 적용하였다.

• KIEAE Journal
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• 제12권1호
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• pp.29-34
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• 2012

As a series of studies about natural ventilation driven by wind in basement parking lots of apartment, the influence of opening size and surrounding buildings on ventilation rate was analyzed. Natural ventilation in underground parking lots almost rely on wind than temperature difference. To investigate natural ventilation driven by wind, wind tunnel tests by using scale model and tracer gas method were conducted. $CO_2$-gas concentration was measured, natural ventilation rates were calculated. The experimental results showed that the natural ventilation rate is more reliable to wind direction and surrounding building than opening size and distance between buildings. It was verified that surrounding buildings play a principal role in increasing air flow rate by accelerating wind speed, and growing turbulence intensity. And it showed that ventilation performance is able to be increased by oblique wind to entrance ramp than head on wind in underground parking lots with surrounding buildings.

• 한국대기환경학회지
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• 제11권3호
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• pp.273-278
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• 1995

This study is to estimate the ventilation volume by the traffic that originated from driving automobiles for two tunnels (Kugi tunnel and Kumhwa tunnel) that adopted natural ventilation system among tunnels of Seoul, and on the basis of which, we estimated the ventilation velume at various conditions. With the result of the estimation, we will present the basic method that can be operated with the optimum condition for the ventilation system. Estimating the predicted ventilation volume in the tennel by the pollutant concentration, we used traffic volume and CO emission data by the automobile speed and CO concentration in the tunnel. And, when we estimated the traffic ventilation volume by natural and traffic ventilation force, we used traffic volume, automobile speed, tunnel area, automobile area data and so on. As the result of simple regression between predicted ventilation volume and traffic ventilation volume, we attained the regression coefficient 0.88, and achieved the relation form that predicted ventilation volume equal 0.12x traffic ventilation volume-92, 000. Using this equation, we estimated the ventilation volume to satisfy the enviromnental standards of several space, and calculated the required volume for mechanical ventilation. Incase of Kumhwa Tunnel, there is a need of mechanical ventilation all day long to satisfy air quality standard 9 ppm for 8 hours average and 10 ppm for the indoor air quality standard of public facilities.

• 한국터널지하공간학회 논문집
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• 제11권4호
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• pp.395-401
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• 2009

장대터널의 환기 및 방재시스템 설계시 주요한 요소설계인자 중 하나인 자연환기력은 그 중요성에도 불구하고 관련 영향변수들의 상호관계는 정량화가 매우 복잡하여, 자연환기력에 의한 유입 자연풍에 관한 설계기준을 정량적 근거하에서 제시하고 있지 못하다. 최근 발생한 터널화재에 의한 문제 및 터널 이용자에 의한 보다 나은 공기질에 대한 요구 등으로 터널 환기시스템의 최적화가 시급히 필요하며, 따라서 최적화의 주요 설계인자인 자연환기력에 대한 연구가 절실히 요구된다. 본 연구에서는 국내 최장대 도로터널로 계획된 인제터널(연장 10.9 km)을 대상으로 자연환기력의 예측을 목적으로 하였다. 지형적 요인에 의한 외부풍의 풍압에 기인하는 자연환기력의 최대 가능수준을 예측할 수 있는 기압장벽고의 개념을 적용하여 외부풍에 의한 자연환기력을 추정하고 터널내외부 공기 밀도차로 인한 굴뚝효과에 따른 자연환기력을 동시에 분석하였다.

• 설비공학논문집
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• 제29권4호
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• pp.175-184
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• 2017

With the improvement of living standards, the ventilation for the mitigation of indoor or outdoor air-pollution problems has recently attracted a lot of attention. Consequently, the ventilation for the supply of outdoor fresh air into a room is treated as an important building-design factor. The ventilation is generally divided into the forced and natural types; here, the former can control the ventilation rate by using mechanical devices, but it has the disadvantages of the equipment costs, maintenance costs, and noise generation, while the latter is applied to most workshops due to the absence of noise and the low installation and maintenance costs. In this experimental study, the ventilation performance of a typical rotating-type natural ventilator, which is called a "wind turbine," was investigated with the outdoor-wind velocity and the indoor/outdoor-temperature difference. From the experiment results, it was confirmed that the temperature difference of $10^{\circ}C$ corresponds to the ventilation driving force with an outdoor-wind velocity of 1.0 m/s. Additionally, the intake-opening area of a building also exerts a great effect on the ventilation rates.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.71-74
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• 2008

This paper aims at studying the key design elements for the optimal ventilation system design, developing the design models and suggesting the design guidelines. The key elements include the basic exhaust emission rate, wall friction coefficient, vehicle drag coefficient and slip streaming effect, jet fan operating efficiency, natural ventilation force and installation scheme for jet fans and ventilation monitors in tunnel. The design models developed in this study are one-dimensional ventilation simulator to analyze the air flow, pressure profile and pollutant dispersion inside and outside tunnel, expert model to choose the optimal ventilation method, and the ventilation characteristic chart to evaluate the preliminary ventilation system. The study results are reflected in the design guideline for road tunnel ventilation system.

• 국제초고층학회논문집
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• 제2권4호
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• pp.293-314
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• 2013

Double-Skin Façade (DSF), which is a kind of passive indoor environmental control technique, is effective way to control environmental loads while maintaining the transparency especially in perimeter zone and hence the adoption example of DSF keep increasing recently. The objective of this study was to perform a field survey of air quality environment with natural ventilation through DSF and thermal environment within office building with six stories during a mild climate period in Japan. Moreover, to understand the comprehensive environmental performance of the target building, questionnaire survey was conducted to subjectively evaluate the productivity and satisfaction with the environmental factors in office space. In this field measurement, there was a positive correlation between the DSF internal ventilation flow and the amount of solar radiation on the DSF normal surface; the primary driving force for ventilation in the DSF was considered to be the buoyancy force caused by solar radiation. The results of questionnaire survey with regard to productivity level indicated the need for improvement in the thermal (temperature) and spatial environment (room size and furniture placement).

• 한국태양에너지학회 논문집
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• 제24권2호
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• pp.25-31
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• 2004

Ventilation through air vent system in a building envelope is expected to be an effective measure to release solar radiation. An external surface of a wall absorbs solar radiation and transfers it to the air in the cavity. The warmed air gets buoyant force. So when openings are provided at the top and bottom of the cavity, the warmed air is released through the top opening and cooler outside air replaces the space in the cavity. This reduces the further heat transmission into the built environment. This natural ventilation effect seems to be steady and strong. So because of the cavity and the openings, the cooling load reduction by natural ventilation is believed to be considerable.

• 한국산업보건학회지
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• 제19권3호
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• pp.240-249
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• 2009

HRSG(Heat Recovery Steam Generator) building is large enclosed structure included various heat sources. This building needs to appropriately keep internal air temperature for worker's safety and operability of control devices. In this study, ventilation analysis is performed to find proper ventilation method for temperature control. Ventilation analysis is applied to entire internal space of the building with standard $k-{\varepsilon}$ model and enhanced wall treatment because of large size of the structure. And the ventilation method is considered natural and forced convection with two louver structures which has damper or not. Louver structure affect directly air circulation in near HRSG and lower region of the building. Forced ventilation provides strong inertial force which cause upward airflow. From the analysis, it is found that design requirement for internal air temperature can be satisfied by forced ventilation method with louver structure without damper.

• 한국생물환경조절학회:학술대회논문집
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• 한국생물환경조절학회 1999년도 학술발표논문집
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• pp.126-129
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• 1999

Natural ventilation is achieved by air exchanges through multiple openings due to natural pressure variations inside and outside the greenhouse. Wind is the primary driving force making natural ventilation systems very difficult to design properly because of variations in wind velocity and direction. The optimization of these systems for acceptable climate control requires a thorough knowledge of the airflow rates and patterns as related to weather conditions and greenhouse structural details. (omitted)