• 항공우주기술
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• 제12권1호
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• pp.207-212
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• 2013

스월 제트 전단층 제어에 관한 인공적 방법의 가능성을 연구하기 위해 전단 자극장치가 제안되었다. 주요 구성품으로는 두개의 동심 아음속 노즐 그리고 유동 자극 생성을 위한 내부 돌기 등이다. 돌기의 숫자는 방위각 방향의 다양한 모드를 유도 할 수 있도록 변화가 가능하다. 획득된 속도 결과는 평면 contour plot과 공간 입자 궤적으로 표현하였다. 다양한 자극 모드에서의 결과 값들이 기준 값(무자극)과 비교되었다. 결과적으로, 새로 고안된 기법이 스월 유동 와류 구조 제어에 있어 효과적인 방법임이 입증되었다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2008년도 제31회 추계학술대회논문집
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• pp.149-152
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• 2008

초소형 터보제트엔진에 적용되는 슬링거연소기를 개발하고 리그시험을 수행하였다. 슬링거연소기에 적용하기 위하여 고속으로 회전하는 회전연료노즐을 설계, 제작하고 분무시험을 통해 연소에 적합한 액적크기와 분포를 얻었다. CFD를 이용해 연소기 내부 유동장을 해석하였으며, 연소리그시험을 통해 설계점에서 11.2%의 압력손실, 99.8%의 연소효율을 달성하였다.

• 동력기계공학회지
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• 제5권3호
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• pp.31-37
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• 2001

A study to obtain the enhancement of turbulence at low Reynolds number is carried out by adding ultrasonic force into the jet flow field of a coaxial circular pipe which can afford the sufficient data of flow characteristics with the shear flow and turbulence flow in spite of its simple shape. A coaxial circular flow field is made vertically in a large and transparent acryl tank. The time mean velocity vector, distribution, kinetic energy and turbulence intensity formed in the complex flow field of turbulence enhancement are investigated, observed and discussed at Reynolds number of 2,000, 3,000 and 5,000 by using PIV measurement, in results, the validity of ultrasonic to obtain the enhancement of turbulence is certified.

• 한국가시화정보학회지
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• 제5권1호
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• pp.43-48
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• 2007

Micro-PIV(particle image velocimetry) has been widely used to measure the velocity of micro flow. Although this micro-PIV method can give accurate 2D instantaneous velocity information of mea-surement plane, it cannot resolve the out of plane component of velocity vectors. Lots of the micro fluidic devices generate three-dimensional flow and 3D measurement of velocity is useful to understand the physics of micro flow phenomena. In this study, we constructed stereoscopic micro-PIV(SMPIV) system and applied this method to the impinging micro jet flow. The results show that this method can produce accu-rate 3D reconstruction of micro jet flow.

• 한국가시화정보학회:학술대회논문집
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• 한국가시화정보학회 2005년도 추계학술대회 논문집
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• pp.28-35
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• 2005

Experiments were conducted to show the characteristics of the flow on triple parallel plane impinging jets. Measurements of mean velocity components and turbulent intensities were carried out with a particle image velocimetry(PIV) to investigate the flow field generated by the air issued from three identical plane parallel nozzles and mixed with the ambient air. The measurements range of these experiments were Reynolds number of 5000 and 1000 based on the nozzle width and the case of nozzle-to-plate distances were two times, six times and ten times the width of the nozzle. Results show that recirculation region of Re=5000 is the stronger than that of Re=1000. Therefore, velocity loss of centerline for Re=5000 that shows strongly recirculation region takes effect greatly.

• Journal of Advanced Marine Engineering and Technology
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• 제25권6호
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• pp.1330-1335
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• 2001

A present study is the flow characteristics of impinging jet by PIV measurement and numerical analysis. The flow characteristics of impinging jet flow are affected greatly by nozz1e inlet velocity An circular sharp edged nozzle type($45^{\circ}$ ) was used to achieve uniform mean velocity at the nozz1e inlet, and its diameter is 10 mm(d). Therefore, the flow characteristics on the impinging jet can be changed largely by the control of main flow In this parent study, we investigate the effects of inlet velocity, its variable is nozzle inlet Reynolds numbers (Re=1500, 3000, 4500, 6000 and 7500)

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2000년도 춘계학술대회 논문집(Proceeding of the KOSME 2000 Spring Annual Meeting)
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• pp.165-170
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• 2000

A fundamental experimental study for a substitute proposal to super-speed craft propulsion system called underwater ram-jet propulsion by high pressure air ejection as driving force was investigated. for basic study of effect of ram-jet propulsion performances ismple underwater ram-jet flow field was established and PIV(Particle Image Velocimetry) method was adopted to analyse the jet-induced flow appearing at ram intake mixing chamber and nozzle. Some flow dynamics relating to the high-speed ejector effect were discussed for the basic understanding for the ram-jet propulsion principle.

• 석유와에너지
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• 1호통권228호
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• pp.62-69
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• 2002

2015년까지 국내석유수요는 연평균 1.4% 증가하여 총 8억9,648만 배럴을 기록할 것으로 전망된다. 대한석유협회는 지난 12월 27일 석유수요전망위원회를 통해 「2015년 석유수요전망」을 발표하면서 오는 2005년까지 연평균 1.6%, 10년까지 1.5%, 15년까지는 1.3%로 점차 증가율이 둔화될 것으로 분석하고 그 수준도 1~2%에 그쳐 장기적 안정기에 접어들 것이라고 했다. 부문별로는 산업과 수송부문에서의 수요는 지속적으로 증가될 것으로 예상되고 있으나 LNG등 타에너지로의 연료대체가 이뤄지고 있는 가정상업부문과 발전, 도시가스부문의 수요는 감소할 것으로 전망했다. 유종별에 있어서도 휘발유와 경유, 제트유 등 수송용 연료의 수요는 증가하는 반면 가정상업용인 등유, 프로판과 환경규제를 많이 받는 B-C유의 수요는 점차 낮아질 것이라고 분석했다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.823-826
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• 2002

Experiments were conducted to show the characteristics of the flow on unventilated parallel plane jets. Measurements of mean velocity components and turbulent intensities were carried out with a particle image velocimetry. The measurements range of these experiments was Reynolds number of 5300 based on the nozzle width and the cases of nozzle-to-nozzle distance were 4, 6, 8, and 10 times the width of the nozzle. Results show that a recirculation zone with a sub-atmospheric static pressure was bounded by the inner shear layers of the individual jets and the nozzles plate. The positions, where maximum value of mean turbulent intensities and mean turbulent kinetic energy show, were at the same position with the merging point. The spread of jets in the merging region increases more rapidly than that of jets in the converging and the combined region. As nozzle-to-nozzle distances were increased, it was shown that merging and combined lengths were shorter.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.513-516
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• 2002

The flow structure and heat transfer characteristics of a turbulent buoyant jet were investigated experimentally. The instantaneous temperature and velocity fields in the near field were measured using a two-frame PIV and PLIF techniques. A thin light sheet illuminated a two-dimensional cross section of the buoyant jet in which Rhodamine B was added as a fluorescent dye. The intensity variations of LIF signal from Rhodamine B molecules scattered by the laser light were captured by a CCD camera after passing an optical filter. By ensemble averaging the instantaneous temperature and velocity fields, the mean temperature and velocity fields as well as the spatial distributions of turbulent statistics were obtained. The results show the flow structure and convective heat transfer of the developing shear layer in the near field.