• Journal of Bio-Environment Control
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• v.11 no.1
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• pp.45-49
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• 2002

온실에서 환기는 온실내외의 공기를 교환하여 온실내부의 환경을 조절하는 수단으로 활용되고 있으나 조절 목표는 한계가 있기 때문에 보조수단의 역할을 한다. 주년재배용 대규모 온실 설계시 해결해야 할 문제중의 하나가 여름철의 고온장해이며 이는 온실의 자연환기 성능과 밀접한 관계를 가지고 있다. 본 강좌에서는 온실의 자연환기에 관한 기본적인 내용을 요약하여 정리하고, 온실구조가 자연환기 성능에 미치는 영향을 파악하기 위하여 수치해석으로 온실의 필요환기량, 측창과 천창의 면적비와 온실 폭이 자연환기 성능에 미치는 영향을 분석하였다. 온실의 자연환기 성능을 향상시키기 위해서는 주어진 조건하에서 가능한 한 측창과 천창의 면적을 동일하게 설계해야 하고 주년재배용 대규모 온실에서는 폭이 대략 50m이상이 되면 자연환기성능을 기대하기 어렵기 때문에 유의해야 할 것으로 판단된다.

• Journal of Korean Tunnelling and Underground Space Association
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• v.16 no.6
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• pp.561-571
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• 2014

The standards of ventilation system for bi-directional tunnel have not been established now. For this reason, with regard to the bi-directional tunnel below 1km, some problems have been appeared in ventilation capacity designing and in determining whether the mechanical ventilation system is needed or not for each case. In this study, we examine the characteristics of natural ventilations, analyze ongoing ventilation design cases for bi-directional tunnels and classify those cases into two groups. This study is carried out about the capability of using natural ventilating system by calculation of reasonable ventilation capacity in bi-directional tunnel and review of relationship between natural wind speed ($Vr^*$) and required speed(Vreq). This paper aims at providing a basis data for bi-directional tunnel ventilation design standards.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.3
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• pp.183-192
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• 2005

Natural ventilation in radioactive waste repositories is considered to be less efficient than mechanically forced ventilation for the repository working environment and hygiene & safety of the public at large, for example, controlling the exposure of airborne radioactive particulate matter. It is, however, considered to play an important role and may be fairly efficient for maintaining environmental conditions of the repository over the duration of its lifetime, for example, moisture content and radon (Rn) gas elimination in repository. This paper describes the feasibility of using natural ventilation which can be generated in the repository itself, depending on the conditions of the natural environment during the periods of repository construction and operation. Evidences from natural cave analogues, actual measurements of natural ventilation pressures in mountain traffic tunnels with vertical shafts, and calculations of airflow rates with given natural ventilation pressures indicate possible benefits from passive ventilation for the prospective Korean radioactive waste repository. Natural ventilation may provide engineers with a cost-efficient method for heat and moisture transfer, and radon (Rn) gas elimination in a radioactive waste repository. The overall thermal performance of the repository may be improved. The dry-out period may be extended, and the seepage flux likely would be decreased.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.29 no.10
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• pp.44-46
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• 2000

자연환기를 건물에 적용하는 주된 목적은 "실내 환경수준을 충족시키기 위해 필요한 초기투자 및 유지비용을 절감하기 위해서" 이다. 따라서, 합리적인 환경계획을 수립하기 위해서는 "자연환기를 적용하는 것이 유효한가\ulcorner 유효하다면 어떤 전략을 채용할 것인가\ulcorner" 하는 것이 계획단계에서 반드시 검토되어져야 한다. 설계자는 합리적인 판단을 위해서 다양한 정보를 필요로 하게되며 이 과정에서 다양한 해석도구가 이용될 수 있다. 본보에서는 자연환기 설계단계에서 요구되는 각종정보와 그 해석도구의 특성에 대하여 고찰해 보고자 한다.

• Land and Housing Review
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• v.5 no.4
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• pp.325-332
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• 2014

The purpose of this study was to measure the airtightness and Air-Flow Performance for 7th house of small apartment houses adopted window frame-type natural ventilation. All window and living room door is provide with window frame-type natural ventilation, and there is provide with manual controller. As the object of measurement, the 6th type small apartment houses with area of $33m^2$ to $51m^2$ was selected. airtightness performance was measured at the front door using Blower door system. We measured ventilation rate per hour on 50Pa pressure different between inside and outside by the 1st to 6th cases. As a result, when the natural ventilation frame was closed, average amounts are shown as the ventilation rate per hour were 2.27ACH (CASE1). and the result is similar to general apartment house (1.65~4.28ACH). When the natural ventilation frame was open, average amounts are shown as the ventilation rate per hour were 5.87ACH (CASE6). In addition, that's a 3.6ACH increased more than CASE1.

• Land and Housing Review
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• v.6 no.4
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• pp.215-220
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• 2015

The purpose of this study was to comparative analyses of energy performance in apartment houses adopted window frame-type natural ventilation, under-floor air distribution ventilation and heat recovery ventilation. As the object of energy simulation, the three type ventilation system with area of $84m^2$ was selected in apartment house. As a result, when the ECO2 simulation was performed, the 1st requirement quantity per annual were $159.9kWh/m^2yr$(CASE1, Natural Ventilation), $179.7kWh/m^2yr$(CASE2, Under-floor Air Distribution Ventilation) and $161.0kWh/m^2yr$(CASE3, Heat Recovery Ventilation).

• Tunnel and Underground Space
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• v.19 no.3
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• pp.226-235
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• 2009

Force induced by the natural ventilation in tunnel is likely to generate adverse influences on the airflow during the normal operation and create even more unfavorable circumstances during the tunnel fire. The influence of the natural ventilation is required to take into account in designing and operating the ventilation as well as safety systems. The magnitude of natural ventilation force depends on a variety of factors associated with the topographical, meteorological and physical features of tunnel. Unfortunately, at this moment those are difficult to quantify and none of the countries has suggested its estimation method in the design guideline. This study aims at quantifying the natural ventilation force at a local highway tunnel by three different methods. The first method employes direct measurement of the pressure at portals, while the second applies a stepwise approach to eliminate the piston effect ahead of deriving the natural ventilation force and the third method uses the concept of barometric barrier.

• 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.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.188-190
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• 1999

현재 지하주차공간의 자연환기방식에 대한 우리나라 건축법규의 기준은 150m$^2$ 이내마다 1개소이상의 외기와 면하는 2m$^2$이상의 개구부를 천창 혹은 Dry Area를 설치하도록 규정하고 있다. 이 지하공간에서의 자연환기는 풍력, 온도차, 차량출입구에 의한 환기를 들 수 있으나 주로 풍력에 의한 환기가 대부분을 차지한다.(중략)

• Tunnel and Underground Space
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• v.21 no.6
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• pp.518-525
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• 2011

In this study, the natural ventilation pressure resulting from the large altitude difference which is a characteristic of high radioactive waste repository and the caloric value of the heat emitted by wastes was calculated and based on the results, natural ventilation quantities were calculated. A high radioactive waste repository can be considered as being operated through closed cycle thermodynamic processes similar to those of thermal engines. The heat produced by the heating of high radioactive wastes in the underground repository is added to the surrounding air, and the air goes up through the upcast vertical shaft due to the added heat while working on its surroundings. Part of the heat added by the work done by the air can be temporarily changed into mechanical energy to promote the air flow. Therefore, if a sustained and powerful heat source exists in the repository, the heat source will naturally enable continued cyclic flows of air. Based on this assumption, the quantity of natural ventilation made during the disposal of high radioactive wastes in a deep geological layer was mathematically calculated and based on the results, natural ventilation pressure of $74{\sim}183$Pa made by the stack effect was identified along with the resultant natural ventilation quantity of $92.5{\sim}147.7m^3/s$. The result of an analysis by CFD was $82{\sim}143m^3/s$ which was very similar to the results obtained by the mathematical method.