• 한국강구조학회 논문집
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• 제21권3호
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• pp.289-299
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• 2009

본 연구는 각주형 저층건축물에 작용하는 지점별 풍압을 다점동시측정시스템을 이용하여 건물 폭과 깊이변화에 따른 평균풍압분포 특성에 대한 기초적인 결과를 정리한 것이다. 본 실험에서는 건물의 폭과 깊이를 변화시킨 5개의 각주형 풍압실험모형이 사용되었으며, 풍동실험은 금오공과대학교 소재 토출식 경계층풍동에서 실시하였다. 실험결과는 저층건축물의 건물 폭 및 깊이의 변화에 따른 저층건축물의 평균풍압분포 변화경향을 건축물의 풍상면, 풍측면 및 풍하면 중심으로 특성을 분석하였다. 실험결과를 토대로 저층건축물의 구조골조 설계용 풍하중을 합리적으로 산정하기 위해 필요한 새로운 풍압계수 및 간략한 약산식을 제시하였다.

• 한국안전학회지
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• 제5권1호
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• pp.41-48
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• 1990

In this study the explosion characteristics of terephtalic acid dust(PTA) was investigated with the Hartmann type apparatus. The minimum ignition energy, minimum explosible concentration, flame propagation velocity, explosion pressure, explosion pressure rise rate and the effect of inert dust(talcum) on explosion characteristics were measured. Flame velocity was 50m/s at 700g/m$^3$ concentration, and the explosion pressure and explosion pressure rise rate were most likely with that of gas explosion. It was found that an inert dust acts as a heat sinker and it disturbs the combustion of flammable dust, as a result, explosion pressure and explosion pressure rise rate were decreased and minimum explosion concentration was increased with increasing the fraction of talcum dust in PTA.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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• pp.41-42
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• 2006

A study on the combustion characteristics by using Emulsion Fuel in Diesel Engine is performed experimentally. In this paper, the experiments are performed at engine speed 1800rpm, emulsion fuel ratio is 0%, 10%, 20%, and main measured items are specific fuel consumption, pressure, ratio of pressure rise, rate of heat release etc. The obtained conclusions are as follows. 1) Specific fuel consumption increase maximum 19.8% at low load, but is not effected at full load. 2) Ratio of pressure rise and rate of heat release are about the same in the case of 10% and 20% of emulsion fuel ratio. 3) Cylinder Pressure increase 11.7%, ratio of pressure rise increase 60.4% in case of emulsion fuel ratio 20% at full load. 4) Rate of heat release increase 76.9% in case of emulsion fuel ratio 20% at full load.

• 한국주거학회논문집
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• 제16권2호
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• pp.75-82
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• 2005

The High-rise Residential Buildings are recently consuming a lot of energy because of the vertical height rise in case of supplying cold and hot water. It is required to a appropriate solution in occurring discomfortable use and unexpected conditions of High-rise Residential Buildings on account of the difference of water supply pressure on top and bottom floor, faucet outlet pressure rise. Thus, the purpose of this study is to research on practical use status of Cold and Hot Water Supply System through Question Survey in High-rise Residential Buildings and to analyze problems.

• Wind and Structures
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• 제36권1호
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• pp.41-60
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• 2023

The effect of cladding panel size on the size reduction factor (SRF) of extreme area-averaging wind pressure (EAWP) on the facades of a high-rise building is often ignored in previous studies. Based on wind tunnel tests, this study investigated the horizontal and vertical correlations of wind pressure on the facade claddings of square-section high-rise buildings. Then, the influencing parameters on the SRF of the EAWP on the cladding panels were analyzed, which were the panel area, panel width, panel length and building width. The results show clear regional distinctions in the correlation of wind pressures on the building facades and the rules of the horizontal and vertical correlations are remarkably different, which causes the cladding size ratio to impact the SRF significantly. Therefore, this study suggests the use of the non-dimensional comprehensive size parameter b^𝜶h^1-𝜶/B (𝜶 is the fitting parameter) determined by the cladding panel horizontal size b, cladding panel vertical size h and the building width B rather than the cladding panel area to describe the variation of the EAWP. Finally, some empirical formula for the SRF of the EAWP on the cladding of a high-rise building is proposed with the nondimensional comprehensive size parameter.

• 한국강구조학회 논문집
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• 제21권3호
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• pp.245-255
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• 2009

산업용 건축물은 일반적으로 박공지붕형 저층의 형태로 많이 건설된다. 본 연구는 박공지붕형 저층건물의 풍압분포와 특성을 알아보기 위하여 풍동실험을 수행하였다. 풍동실험은 경사각 변화에 따른 외장재용 피크외압계수 분포양상을 알아보기 위하여 동일한 폭과 높이, 길이를 가지지만 지붕 경사각이 서로 다른 7가지의 모형을 제작하여 실험하였다. 실험결과 지붕과 벽면의 모서리 부분에서 최대 피크외압계수가 나타났으며, 이를 KBC-2005 및 각국의 기준과 비교하여 보았다. 실험에 의한 피크외압계수는 AIJ-2004와 매우 유사하게 나타났지만 KBC -2005보다는 다소 크게 나타났다.

• 설비공학논문집
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• 제17권3호
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• pp.268-276
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• 2005

The aim of this paper is to suggest one efficient method for the various requirements of performance during the process designing and producing an impeller. The study considers that the revisions of a pitch angle of an impeller at an axial turbo fan affect an air flow rates and a static pressure rise. The axial turbo fan specified with the 250 Pa maximum static pressure and 1300 CMH fan air flow rates was tested and analyzed by CFD. The Numerical results show that the air flow rates are calculated to 1,175 CMH, 1,223 CMH, 1,270 CMH, 1,340 CMH and 800 CMH in cases that the pitch angles are $44^{\circ},\;49^{\circ},\;54^{\circ},\;59^{\circ},\;and\;64^{\circ}$ respectively. Also the static pressure rises are shown to 108 Pa, 122Pa, 141 Pa, 188 Pa and 63 Pa at the same cases. The air flow rate is increased linearly according to the changes of the pitch angle from $44^{\circ}\;to\;59^{\circ}$ and the maximum air flow rate passing the impeller is increased to $13\%$ over at the case of $59^{\circ}$ pitch angle compared with the reference case of $54^{\circ}$ pitch angle. The static pressure rise is increased linearly according to the changes of the pitch angle from $44^{\circ}\;to\;54^{\circ}$, too. The static pressure rise at the $59^{\circ}$ pitch angle is increased to $33\%$ over compared with the $54^{\circ}$ pitch angle. The result shows that the revisions of pitch angle make the static pressure rise increase widely. However the air flow rates and the static pressure rise at the $64^{\circ}$ pitch angle are suddenly decreased because of over-changed pitch angle.

• 오토저널
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• 제7권1호
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• pp.35-42
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• 1985

This paper describes an experimental study of the effect of injection timing on the combustion characteristics in four stroke cycle diesel engine with direct injection type combustion chamber. The effect of injection timing and compression ratio of engine on the combustion characteristics are investigated. Experimental results of combustion characteristics in cylinder show that the combustion pressure and the rate of pressure rise decrease in accordance with the retard of fuel injection timing. It is observed that the rate of pressure rise in cylinder is increased an increase in the compression ratio of engine. The effect of the fuel injection timing on the frequency of cylinder pressure brings about the same trend of the maximum rate of pressure rise in cylinder.

• 한국화재소방학회:학술대회논문집
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• 한국화재소방학회 2008년도 추계학술논문발표회 논문집
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• pp.235-238
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• 2008

High-rise buildings with stack effect caused by the foreclosure, which significantly delayed the spread of a fire in effects of these stack effect driving force said. In this research on the stack effect of the lobby if the pressurization of the stairwell analysis of the pressure distribution of the CONTAMW. Overall, the pressurization of the lobby makes it stairwell amount of pressure(+) to the zone in pressure designed to prevent the spread of smoke control performance and found that, the way a normal state and sub-pressurization in the stairwell with stack effect of the turbulence Such as the formation of the upper flow, but, in the upper atmosphere with pressurization was formed by the underlying trend.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.409-414
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• 2009

Since cryogens are stored at very low temperatures, the cryogenic storage systems are quite sensitive to heat leaks. Even though the vessel operated under sealed condition with vacuum insulation and reflective coatings are used, the heat leakage into the vessel is still unavoidable. Therefore, this paper concerns with numerical study of self-pressurization used to analysis the optimum design with the variation volume fraction, effect of heat flux and storage pressure of liquid nitrogen. The result shows that as the volume fraction increases, the pressure rise reduces and the relatively at atmosphere pressure is better than the higher one. In addition, higher heat flux leads the pressure rise increases faster than low one. The additional of heat pipe system to reduce the pressure rise rate also has been done. By this comparison, the optimum design for storage umbilical cord blood can be selected.