• 터널과지하공간
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• 제27권4호
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• pp.195-204
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• 2017

본 사례연구에서는 신림~봉천터널 지하환기소 대단면 터널의 시공 사례를 소개하였다. 환기갱(폭 7.8 m, 높이 6.6 m)에서 환기소(축류팬실, 폭 20.8 m, 높이 12.3 m)로 터널 단면이 확대되는 구간에 대해 안전성 및 시공성 등을 고려하여 점진적인 확대 굴착 방안 및 Q 시스템을 이용한 확폭 구간의 임시 보강 방안이 검토되었다. 확폭이 완료된 이후 대단면 터널은 현장의 암반조건을 확인하고, 전산해석을 이용한 터널의 안정성 검토 등을 통해 암반등급에 따라 굴진장을 일부 조정하고, 터널 상부 굴착을 분할 없이 전단면 굴착으로 변경하여 시공성을 향상시켰다. 본 사례연구에서 소개한 시공 사례가 향후 유사한 조건의 지하환기소 또는 4차로 도로 등의 대단면 터널의 설계 및 시공에 유용한 참고 자료가 될 수 있기를 기대한다.

• 한국농공학회논문집
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• 제50권1호
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• pp.39-47
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• 2008

Most of the broiler houses in Korea have experienced problems on controlling the environmental conditions such as suitability, stability and uniformity of rearing condition inside the broiler house. It is very critical which if not properly controlled, would cause serious stress on the chickens. It is therefore urgent to develop optimum designs of naturally ventilated broiler house which is appropriate to the four seasons of Korea. Field experiment for this matter is very difficult to conduct due to the unpredictable and uncontrollable weather condition. In this study, the heating load of a naturally ventilated broiler house was calculated using TRANSYS 15 BES program while internal climate and thermal condition were computed using Fluent 6.2. The computed resulted of the conventional ventilation system (A) and upgraded ventilation system (B) (Seo et al, 2007) were compared with each other for cold season. The results of the Building Energy Simulation(BES) indicated that the system B, the upgraded ventilation system made 8% lower total heating load and 47% lower at only the broiler zone compared to the conventional broiler house. Considering the entire broiler house, the existence of middle ceiling made the heating energy 11% lower required than without middle ceiling. Accordingly, the system B with middle ceiling was found to save heating energy by 20% in average. This study showed that the BES program can be a very powerful to effectively compute the energy loads of agricultural building while the energy load is very close related to ventilation efficiency.

• 한국입자에어로졸학회지
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• 제16권4호
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• pp.73-94
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• 2020

Particulate infectious sources, including infectious viruses, can float in the air, causing airborne infections. To prevent indoor airborne infection, dilution control by ventilation and indoor air cleaners are frequently used. In this study, the risk of airborne infection by the operation of these two techniques was evaluated. In case of dilution control by ventilation, a high efficiency air filter was embedded at the inlet of supply air. In this study, infectious source reduction devices such as indoor air cleaner include all kinds of mechanical-filters, UV-photo catalysts and air ionizers through which air flow is forced by fans. Two mathematical models for influenza virus were applied in an infant care room where infants and young children are active, and the risk reduction efficiency was compared. As a result, in the case of individually operating the ventilator or the infectious source reduction device, the airborne infection risk reduction efficiencies were 55.2~61.2% and 53.8~59.9%, respectively. When both facilities were operated, it was found that the risk of airborne infection was reduced about 72.2~76.8%. Therefore, simultaneous operation of ventilation equipment and infectious source reduction device is the most effective method for safe environment that minimizes the risk of airborne infection of respiratory infectious diseases. In the case of a space where sufficient ventilation operation is difficult, it was found that the operation of an infectious source reduction device is important to prevent the spread of infectious diseases. This study is meaningful in that it provides an academic basis for strategies for preventing airborne infection of respiratory infectious diseases.

• 한국산학기술학회논문지
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• 제16권3호
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• pp.1600-1604
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• 2015

현대 주택이 고기밀 고단열로 건축되기 때문에 에너지 절감의 이점이 있는 반면 오염된 공기로 인한 많은 부작용이 발생하고 있다. 이런 부작용을 해결하기 위해 환기장치를 사용하여 실내 공기 환경을 개선하고 있다. 본 연구에서는 폐열회수 환기장치의 일종인 히트파이프를 사용하여 작동유체 충진량 및 환기량에 따른 히트파이프의 환기성능을 시험적으로 평가하였다. 본 연구에서 사용된 히트 파이프는 환기장치에 적용이 가능하도록 분리형으로 제작되었다. 작동유체는 R22이고 유체의 충진량은 40~55(%vol.)로 5(%vol.) 단위로 충진 하였다. 환기량은 전면풍속을 기준으로 0.3~1.5m/s로 0.3 m/s 간격으로 바꿔 가며 측정하였다. 시험결과 최대 효율을 가지는 냉매 충진량이 환기량에 따라 다름을 알 수 있었고, 실험 결과 분석을 통하여 분리형 히트파이프의 환기량에 따른 최적 냉매 충진량을 찾을 수 있었다.

• KIEAE Journal
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• 제14권6호
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• pp.99-104
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• 2014

Recently supply of low energy house is increasing which can enhance energy efficiency and indoor environment comfort. Low energy house have to secure air tightness as well as thermal performance so house become high airtightness and inevitably need heat recovery ventilator to enhance indoor air quality. However, most of current ventilation systems are one-click, controlling the entire space so it causes increasing of heating load and fan power which makes it hard to save energy. Thus, Individual Control system is required which can achieve both enhancing indoor air quality and decreasing heating load and electric fan power. Thereby, in this study, we analyzed the correlation between ventilation and fan power through mock-up experiment and measured ventilation load under individual control system. As a result, under the condition of $24^{\circ}C$ of indoor temperature for 6 month(November to April) in Daejeon, ventilation load by fan speed was $10.9{\sim}19.6kWh/m^2{\cdot}a$ when operated 24 hours and $7.6{\sim}13.7kWh/m^2{\cdot}a$ when operated 12 hours in night time. In addition, it is possible to reduce at most 60% of ventilation load under the individual control system; measured ventilation load was $7.4kWh/m^2{\cdot}a$ when operated 24 hours, and $5.5kWh/m^2{\cdot}$ when operated 12 hours in night time.

• 설비공학논문집
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• 제13권10호
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• pp.982-992
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• 2001

In this paper, the performance of ventilation equipments in enclosed parking garages were investigated for several air distribution systems by numerical method. Air change effectiveness of the non-mixing system was 0.42. It meant that more supply air as much as the design supply air was needed to maintain good indoor air quality. In the high speed nozzle ventilating system which is most expensive one, air change effectiveness was 0.54. Therefore this system satisfied to ventilation design. In the jet fan ventilating systems, air change effectiveness for jet fan ventilating system-A with 18 jet fans and jet fan ventilating system-B with 6 jet fans in circulation mixing arrangement were 0.565 and 0.42 respectively. Jet fan ventilating system-C with 6 jet fans in transport mixing arrangement was 0.535. Jet fan ventilating system-A and jet fan ventilating system-C met the ventilation design. But velocity in jet fan ventilating system-A was over 2.0m/s which is inappropriate in human comfort. Therefore this system is not proper to ventilation. Jet fan ventilating system-C was the optimum one for enclosed parking garages among 5 systems examined in this paper.

• 한국산학기술학회논문지
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• 제16권9호
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• pp.6432-6438
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• 2015

본 논문에서는 피드빈 내부의 온도와 습도를 계측하여 분석하고, NV, EA, SA, $SA{\cdot}EA$환기 시스템을 적용하여 효율적인 관리와 운영방향을 제안한다. 외부기온과 상대습도에 따른 피드빈 내부온도와 습도의 변화를 확인하기 위해 사료 투입 기간과 투입하지 않은 기간을 대상으로 환기시스템을 적용한 후 비교분석 한다. 외부기온과 상대습도의 비교분석을 통해 내부온도는 $SA{\cdot}EA$, 내부습도는 NV, SA환기시스템의 적용과 효율을 확인할 수 있다.

• 한국가스학회지
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• 제6권1호
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• pp.74-80
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• 2002

지하공간에서 천연가스가 고압으로 분출될 때, 이에 응하여 작동되는 환기시스템이 전체 지하공간 내 유동에 미치는 영향은 매우 크며 이에 대한 적정한 선계는 안전성 확보측면에서 매우 중요한 일이다. 본 연구에서는 천연가스 분출 비상시의 유동을 전산해석을 통하여 반밀폐공간 내 천연가스의 농도분포 및 유동특성을 규명함으로써, 내부유동을 가시화하고 상부 환기팬 유$\cdot$무에 따른 환기효율을 비교함으로써 환기시스템의 개선사항 및 설계 방안을 제시하였다.

• 설비공학논문집
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• 제24권3호
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• pp.224-229
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• 2012

The importance of ventilation system is being emphasized by interest of indoor air quality. Especially, heat recovery ventilation system has attracted attention as most effective ventilation plan. Because it can reduce hazardous construction materials, indoor air pollutions, and also can reduce air conditioning energy cost. In heat recovery ventilator, the element core is the most important part. The element core is composed of liner and spacer. And liner and spacer are stacked alternately. On the Liner, heat and humidity transfer are made between supply and exhaust air. And spacer plays a role as a tunnel of exhaust and supply. In this study, we investigated and analyzed the efficiency of a heat recovery ventilator, when the spacer's properties are changed. As a result, difference spacer's properties affect an efficiency of heat recovery ventilator.

• 한국실내디자인학회논문집
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• 제14권3호
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• pp.46-54
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• 2005

This study explored how the elementary schools provided proper interior environments to the students in terms of ecological aspects. 14 cases-7 in Busan and 7 in Osaka which were newly built or remodelled since 2000 were selected. These schools were analyzed based on the eco-school guideline suggested In the former study. The guideline categorizes into three parts: 1) energy efficiency related with lighting, ventilation, heating and insulation, 2) greening, 3) sustainability including recycling water system and use of environmentally friendly materials. The results showed that Korean schools require more systematic planning for natural lighting, ventilation, Insulation, greening and new water system while Japanese schools need use of environmentally friendly materials and consideration for natural lighting, insulation and interior greening. Especially, natural lighting and natural ventilation through roof window, atrium, wind tower and use of natural insulation and blind window system should be basically considered at the Initial planning. Also, this study reveals that ecological approach including greening and natural lighting with various architectural form should be applied in future elementary school design to make the school environment more agreeable and economical.