• Title/Summary/Keyword: 급기비

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A Study on the Performance Improvement of Smoke Control with Smart Dampers (스마트 댐퍼를 적용한 제연 성능 개선에 관한 연구)

  • Choi, Hyun-Jun
    • Proceedings of the Korean Society of Disaster Information Conference
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    • 2023.11a
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    • pp.159-160
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    • 2023
  • 화재가 발생할 때 연기로부터 안전하게 피난과 소방관의 소화활동을 위해 제연설비가 설치되어 있다. 기존의 자동차압·과압 조절형 급기댐퍼는 화재층과 비화재층을 구분하지 못하므로 화재가 발생하지 않는 층에서 피난을 할 경우 화재층이 연기로부터 보호받지 못한다. 스마트 댐퍼를 적용하면 화재층과 비화재층을 구분하므로 화재층을 연기로부터 보호가 가능하다.

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A Study on the Effects of Etching Surface Characteristics on Condensation Heat Transfer in Pre-heating Exchanger (급기 예열 열교환기에서 에칭 표면 특성이 응축 열전달에 미치는 영향에 관한 연구)

  • Seok, Sungchul;Hwang, Seung Sik;Choi, Gyu Hong;Shin, Donghoon;Chung, Tae Yong
    • Journal of Energy Engineering
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    • v.23 no.2
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    • pp.217-222
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    • 2014
  • In order to improve the heat efficiency of the general residential boiler, we performed an experiment of condensation heat transfer to air pre-heating exchanger adhered to the condensing boiler. In this study, surface roughness was imposed on the surface of stainless steel by etching. And in order to evaluate the heat transfer performance on each plate, the counter flow heat exchanger fabricated with polycarbonate in used. As a result, on etching treated plate's overall heat transfer coefficient is higher than the original plate. And etching treated plate during 60 seconds with etchant is the to average 15% compared to bare stainless steel. And we studied the heat transfer enhancement factor through the analysis of surface characteristics using AFM.

A basic study for thermal performance improvement of domestic oil boiler (家庭용 油類 보일러의 熱性能 向上에 관한 基礎設計 硏究)

  • 정진도;이은모;류정인
    • Journal of Energy Engineering
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    • v.4 no.1
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    • pp.31-41
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    • 1995
  • 본 연구에서는 일반 가정에서 많이 쓰이고 있는 15,000 Kcal/hr용량의 유류 보일러에 대한 제반 실험을 통하여 보일러 운전자료를 제공함은 물론 방열코일의 열교환 실험을 통하여 시중에 유통되고 있는 방열코일의 방열량 비교와 공기와 냉각수와의 열관류율을 비교함으로서 보일러 시공에 필요한 기초 자료를 얻었다. 연소에 필요한 급기량은 매연농도가 문제시 되지 않는 Smoke Scale No.가 1 이하인 공기비 1.45 이상으로 운전이 되어야 하며 송수온도는 t2=-0.0781XGw+85($^{\circ}C$)의 실험식으로 표시할 수 있다. 공기중에서 코일의 방열량은 X-L관이 외경의 차이로 인해 동관보다 높게 나타났다.

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진공챔버 내부의 위성표면온도 제어용 비접촉 적외선 발열장치 개발

  • Jo, Hyeok-Jin;Seo, Hui-Jun;Lee, Sang-Hun;Mun, Gwi-Won
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.08a
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    • pp.49-49
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    • 2010
  • 본 논문은 진공챔버 내부에서 위성 표면의 온도를 제어하기 위한 할로겐램프를 이용한 적외선 발열장치의 개발에 관한 것으로, 인공위성이 우주궤도에서 받게 되는 복사에너지를 지상의 진공챔버 내에서 모사하기 위한 비접촉 적외선 발열장치에 관한 것이다. 진공챔버 내에서의 비접촉식 발열 방법 중, 진공환경에서의 오염을 발생시키지 않고, 발열 시간 및 냉각 시간이 가장 짧으며, 높은 열효율로 태양복사에너지를 가장 근사하게 모사할 수 있는 할로겐 램프를 이용한 발열 방법을 적용하였으며, 램프에서 방사되는 열에너지가 위성표면에 균일하게 분포될 수 있도록 위성 표면으로부터의 거리와 램프의 개수, 램프의 배열에 따른 에너지 분포 계산식을 도출하여 적용하였다. 공급 전압에 따른 램프의 저항특성을 파악하여, 원격으로 제어되는 150 VDC, 5 A의 직류전원공급기를 이용해 램프의 발열량을 조절하였으며, 발열량에 따른 위성 표면온도에 대한 해석을 수행하였다. 램프를 이용한 비접촉식 적외선 발열장치 개발을 통해 진공환경에서의 시험대상에 대한 효율적인 열에너지 부과방법 수립이 가능하였다.

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국민생활의 과학화-식생활의 개선과 보건관리

  • Yu, Tae-Jong
    • The Science & Technology
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    • v.9 no.7 s.86
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    • pp.20-22
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    • 1976
  • 고래로부터 인간이 고안한 기술은 수렵, 가축, 농업 등에서 출발해서 기기나 동력을 더 많이 사용하는 형태로 발전해왔다. 그리고 급기야는 자동제어 등에 이르러 인간을 필요로 하지 않는 방향으로 유도되고 있다. 이러한 비인간적인 지향성을 가진 기술의 진보가 초래한것 중에는 인간과 그 사회에 구 많은 마이너스도 있었다. 이러한 기술의 발달을 보다 인간의 이익으로 유도하기 위해 기술평가의 개념이 진보하게 되었다. 이러한 발전으로 식품공업도 많이 변모하였고 식생활의 변화를 필연적으로 가지고 왔다. 식생활과 보건관리는 직접 사람에 직결되는 사항이다. 따라서 다른 여러 기술에 비해 일반국빈의 관심이 높고 정부가 직접 개입하게도 된다. 이러한 기본적인 생각은 식품이나 의약에만 필요한것이 아님은 오늘날의 생활환경을 생각해 보면 자명해 진다. 어떠한 기술도 기본적인 인권이라고 할 수 있는 건강이라든가 생할환경 등의 기본적인 요구를 저해해서는 안 되는 것이다. .

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Experimental Study for the Capacity of Ordinary and Emergency Ventilation System in Deeply Underground Subway Station (대심도 지하역사 승강장 및 대합실 평상시/비상시 급·배기 풍량에 대한 실험적 연구)

  • Jang, Yong-Jun;Lee, Ho-Seok;Park, Duck-Shin
    • Journal of the Korean Society for Railway
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    • v.15 no.6
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    • pp.579-587
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    • 2012
  • Shin-gumho station in Seoul underground subway have been selected to be experimentally investigated and analyzed for the real air supply & exhaust capacity compared to the original capacity of ordinary and emergency condition. The depth of Shin-gumho station is 43.6m which consists of the island-type platform ($8^{th}$ floor in underground) and a two-story lobby (first & second floor in underground). An emergency staircase connects between the platform and the lobby. Hot-wire anemometer, capture hood, wind vane & velocity meter and data acquisition systems are employed to perform the automatic measurement in this experiment. For ordinary case, air supply and exhaust capacity in the lobby were reduced by 34% and 46% compared to the original capacity, respectively. Air supply and exhaust capacity in the platform were reduced by 66% and 38%, respectively. For emergency case, air supply in the lobby was reduced by 42% and air exhaust in the platform was reduced by 28% compared to the original capacity. Therefore, air pollution in the station is expected to be worse in the ordinary environment and smoke control capability in the platform will be weakened in case of fire emergency.

Control of Suspended Dust in Various Ventilation Systems of Cement Packaging Process (시멘트 포장공정에서 환기시스템에 따른 발생분진의 제어)

  • Lee, Seung-Chul;Kim, Soo-Chang;Noh, Kwang-Chul;Park, Myoung-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.10 no.3
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    • pp.463-469
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    • 2009
  • We performed the experimental study on the control of suspended dust in a cement packaging process for various ventilation systems. To effectively remove the dust generated in the cement packaging process, three different kinds of ventilation system, such as local exhaust ventilation, electrostatic scrubber, and local air supply system, were adopted. Dust concentrations in the packaging process were measured with the variation of the airflow rate of the ventilation systems and then their ventilation performance were evaluated. From the results, we knew that the ventilation performance was the best when the local exhaust ventilation and the electrostatic scrubber were simultaneously operated in the packaging process. In the electrostatic scrubber system, the effect of the airflow rate on the indoor dust removal efficiency was negligible so hat he system ust be operated at $2,700m^3/h$ for saving power consumption.

Numerical Study on the Effect of Area Changes in Air Inlets and Vent Ports on the Ventilation of Leaking Hydrogen (급·배기구 면적 변화가 누출 수소 환기에 미치는 영향에 관한 수치해석적 연구)

  • Lee, Chang-Yong;Cho, Dae-Hwan
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.2
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    • pp.385-393
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    • 2022
  • Hydrogen has reduced greenhouse gas (GHG) emissions, the main cause of global warming, and is emerging as an eco-friendly energy source for ships. Hydrogen is a substance with a lower flammability limit (LFL) of 4 to 75% and a high risk of explosion. To be used for ships, it must be sufficiently safe against leaks. In this study, we analyzed the effect of changes in the area of the air inlet / vent port on the ventilation performance when hydrogen leaks occur in the hydrogen tank storage room. The area of the air inlet / vent port is 1A = 740 mm × 740 mm, and the size and position can be easily changed on the surface of the storage chamber. Using ANSYS CFX ver 18.1, which is a CFD commercial software, the area of the air inlet / vent port was changed to 1A, 2A, 3A, and 5A, and the hydrogen mole fraction in the storage chamber when the area changed was analyzed. Consequently, the increase in the area of the air inlet port further reduced the concentration of the leaked hydrogen as compared with that of the vent port, and improved the ventilation performance of at least 2A or more from the single air inlet port. As the area of the air inlet port increased, hydrogen was uniformly stratified at the upper part of the storage chamber, but was out of the LFL range. However, simply increasing the area of the vent port inadequately affected the ventilation performance.

Study on Measurement Method of Air Egress Velocity in Vestibule of Smoke Control System (특별피난계단 부속실 제연설비의 방연풍속 측정 방법에 관한 연구)

  • Lee, Su-Kyung;Hong, Dae-Hwa
    • Fire Science and Engineering
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    • v.25 no.3
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    • pp.85-90
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    • 2011
  • This study of the vestibule of pressurizing smoke control system installed in domestic high-rise buildings for evacuation in case of fire, when the door is open to forming characteristics of the air flow was analyzed using fire dynamics simulator and analyzed of variance. Vestibule which is compartment of the design condition, air flow in the exhaust damper was formed severe turbulence confirming preceding research. The door position is in the range of formed vortex, unsteady flow of air occurs at the point that the door could be confirmed. According to the NFSC 501A, door to symmetrically separate the average of 10 points or more as measured from the average of wind speed to do is based. Under these conditions, it is difficult to measure the characteristics of the upper air flow of upper points. so measuring points are subdivided by more than 64 points method presented in TAB because severe deviation of wind speed.

A Study on Heat and Smoke Exhaust Characteristics from the Subway Fire for Different Ventilation Modes (지하철 화재시 제연모드에 따른 열 및 연기 배출 특성 연구)

  • Chang, Hee-Chul;Yoon, Kyung-Beom;Park, Won-Hee;Kim, Tae-Kuk
    • Journal of the Korean Society of Hazard Mitigation
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    • v.8 no.3
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    • pp.37-42
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    • 2008
  • This study is focused on the numerical predictions for different smoke-control ventilation modes for the subway fire. Smoke-control ventilation mode in the domestic platform is that exhausting for the smoke detected zones while supplying air or stopping any ventilation for other zones in the platform. Three cases of smoke control ventilation modes are considered. First and second case are present running smoke control mode in Korea. The third is that smoke-control ventilation fans equipped in the platform are operated in first 4 minute(platform evacuation time, NFPA130) since then the fans equipped in the platform are stopped and the fans equipped in the tunnels are operated. Distributions of heat, carbon monoxide and visible range are compared at a height of 1.7m(passenger breath/sight height) above the platform. The numerical results show that air supply fan operation in the platform causes the smoke disturbance and a rapid spread of the smoke. The switch-operation with fans in both the platform and tunnel are better than operation with only platform fans in smoke rejection efficiency.