• Journal of Advanced Marine Engineering and Technology
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• 제33권6호
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• pp.822-826
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• 2009

In case of engine room of ship, it uses type 2 ventilation system which supplies outside air forcibly by engine room ventilation fan, and naturally discharges air to outlet through low-pressed casing. The advantage of type 2 ventilation is that it makes inside with bi-pressure status to discharge contaminated materials to outside naturally. However, there is a phenomenon that pressure is greatly different between outside and inside due to huge amount of air supply by engine room ventilation fan. Therefore, we went aboard a container vessel which is on test run to analyze differential pressure with micronanometer by engine load and by combustion air supply method of engine. As a result, as engine load decreases (50, 75, 100%), the differential pressure between outside and inside tends to increase by 35% average, and the difference of pressure was 6.5 times maximum by combustion air supply method of engine.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2008년도 춘계학술논문발표회 논문집
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• pp.251-254
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• 2008

The fact that the major cases of life casualties are from smoke in the fire accidents and the expected steep increase of skyscrapers, huge spaces, multiplexes and huge scaled underground spaces demand establishment of efficient smoke countermeasure. The field experiments on two high buildings of 20 stories and 21 stories are carried out to evaluate the field performance of pressure differential systems for smoke management and the results of experiments are presented.

• 한국화재소방학회논문지
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• 제22권3호
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• pp.194-200
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• 2008

고층건물에서 급기가압 제연시스템과 같이 연기제어를 위해 제연구역에서의 압력차를 이용하는 제연시스템을 성공적으로 설계하고 운영하기 위해서는 건물내 압력형성에 영향을 미치는 건축적 요인들을 검토해야 하며 그중 큰 영향을 발휘하는 요인이 연돌효과이다. 본 연구에서는 고충건물의 피난환경과 제연시스템에 대해 연돌효과가 미치는 영향을 검토하기 위해서 여름과 겨울철에 각각국내 고층건물을 대상으로 급기가압 제연시스템을 가동하면서 피난계단, 부속실 및 거실에서의 압력변화를 측정하고 분석하였다. 연돌효과의 영향이 커지는 겨울철의 경우 급기가압 제연시스템이 가동되면 부속실에서 계단쪽으로의 누기현상과 연돌효과가 합쳐지면서 고층부의 계단실내 압력이 크게 상승하여 재실자가 대피를 위해 피난문을 열고자 할 때 문제가 발생할 수 있다.

• 한국유체기계학회 논문집
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• 제8권1호
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• pp.16-22
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• 2005

This paper presents the method of ROL(Rate Of Loading) improvement for the Motor Operated Gate Valve operated in high differential pressure condition. ROL is one of the most important evaluation parameters for the valve ability. It is close to correlation in stem factor (SF) and appears different value by the differential pressure of fluid. ROL and SF are analyzed by the static test and dynamic test. The obtained result show that the modification of stem factor is very important factor for the ROL improvement. In order to obtain the same value of SF between static and dynamic test, stem and stem nut should be combined appropriately by the repetition test.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2011년도 춘계학술논문발표회 논문집
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• pp.239-244
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• 2011

This study is aimed to develop fundamental technology on the smoke control method by simulation model and scale model simulation technique in pressure differential systems. Thereby, this research aimed to establish design elements and technologies required for smoke control system that is suitable to pressure differential systems of the high-rise buildings in order to minimize the loss of lives and property damage in case of fire.

• 대한기계학회논문집B
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• 제31권2호
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• pp.151-158
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• 2007

The mechanism of power transmission from motor torque to stem thrust and the operation characteristic of each stroke position are analyzed using the diagnostic signal, and effects of differential pressure on the performance of motor operated flexible wedge gate valve are investigated. Test facility consists of 76 mm motor operated valve(flexible wedge type), pump and pipe system. Static and dynamic test are performed separately, and two differential pressure conditions are applied in the dynamic test. To evaluate the performance of valve, test signals for the torque, thrust, current, voltage and stroke length are acquired by using UDS which is diagnosis device for motor operated valve, and each diagnostic signal is analyzed and compared. The characteristic of valve performance factors such as stem factor, rate of loading, valve factor, are evaluated, and these factors are found to be severely influenced by the fluid differential pressure.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2009년도 춘계학술논문발표회 논문집
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• pp.352-357
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• 2009

The fact that the major cases of life casualties are from smoke in the fire accidents and the expected steep increase of skyscrapers, huge spaces, multiplexes and huge scaled underground spaces demand establishment of efficient smoke countermeasure. The core technology for development of smoke management system is analysis tool of fan used in pressure differential system. The development of analysis technology on sirroco-typed fan using experimental and numerical methods are carried out to evaluate the features and performance of fan used in pressure differential systems.

• 한국화재소방학회논문지
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• 제29권6호
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• pp.71-75
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• 2015

최근 건축물은 대형화, 고층화되어 화재발생시 소방대의 활동이 제한되어 화염 및 연기에 의한 인명피해가 증가할 수 있다. 이러한 인명피해를 저감하기 위하여 제연설비가 필수적이며 특별피난계단 부속실 및 비상용승강기 승강장에 급기 가압제연설비를 적용하고 있다. 국가 화재안전기준에서는 부속실 및 승강장과 거실과의 차압을 40 Pa~60 Pa을 요구하고 있으나 실제 현장에서는 60 Pa 이상의 과압이 다수 발생하고 있다. 이러한 과압의 원인은 댐퍼의 누설량의 과다에 의한 것으로 알려져 있다. 과압은 피난자의 문개방을 어렵게 하여 피난을 불가능하게 할 수 있다. 이러한 문제점을 확인하고자 국내에 사용되고 있는 자동차압 과압조절형댐퍼의 누설량을 측정하여 실제 누설량이 얼마인지 분석하였다. 실험결과 제조사 별로 최대 누설량은 $0.154m^3/s$로 나타났으며, 최소 누설량은 $0.090m^3/s$로 나타났다. 이 누설량으로 인하여 과압이 발생하면 피난문 폐쇄력이 증가하여 피난에 방해가 될 수 있으므로 댐퍼의 누설량 제한 기준이 필요하다.

• 한국생산제조학회지
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• 제19권2호
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• pp.204-210
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• 2010

The inner structure of the triangular separate bar (TSB) was improved to enhance the productivity of the TSB flow meter by simplifying the machining process for making the flow meter. The cross section of upstream and downstream pressure chamber in the TSB was changed from triangle to circle, which make it possible to substitute the wire cutting by drilling in the process of machining the pressure chamber. The flow rate characteristics of the flow meters was calibrated with a laminar flow meter. Six kinds of flow meters whose diameters of pressure tap for measuring pressure of both upsteam and downstream pressure chamber were different one another were made. The effects of the pressure tap diameter on the flow rate characteristics of the TSB flow meter was little. The mass flow rate characteristics of the flow meters with increasing a non-dimensional parameter which includes the gas temperature, exhaust gas pressure and differential pressure at the flow meters and atmospheric pressure shows nearly linear relationship with a correlation coefficient of R=0.998.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집E
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• pp.613-618
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• 2001

For the evaluation of operability of MOV(Motor Operated Valve), the precision prediction of thrust/torque acting on the valve is important. In this paper, the analytical prediction method of thrust/torque was proposed. The design basis stem thrust calculation typically considers the followings: Packing thrust, Stem rejection load, design basis differential pressure load. In general, test results show that temperature, pressure, fluid type, and differential pressure, independently and combination, all have an effect on the friction factor. The prediction results of thrust/torque are well agrement with dynamic test results.