• 제목/요약/키워드: crossflow

검색결과 176건 처리시간 0.031초

Crossflow Fan 주변의 유동 (Flows around crossflow fan)

  • 김재원;정윤영
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 춘계학술대회논문집E
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    • pp.678-683
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    • 2001
  • The present work has carried out experimental study on a cross-flow fan system with a simplified vortex wall scroll casing. A cross-flow fan test rig was constructed to obtain pressure rise and volume flow rate for various fan operating conditions. The performance estimation is using a wind tunnel with a motor driven damper for flow rate control and flows are quantitatively visualized by light scattering system with a pulsed laser. Min focus on the visualization is finding a eccentric vortex inside a fan which is a major factor reducing fan efficiency. Comprehensive engineering data are prepared for industrial applications and show a good agreement with a prior work by experimental measurements.

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기체 유동에 수직 분사된 액체의 분해에 대한 수치적 해석 (Numerical Analysis for Breakup of Liquid Jet in Crossflow)

  • 박순일;장근식;문윤완;사종엽
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.1629-1633
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    • 2004
  • Liquid is commonly introduced as transversal jets in venturi scrubber which is one of the gas cleaning equipments. The jet dynamics such as penetration and breakup is of fundamental importance to the dust-collection efficiency. We have developed a model that can numerically simulate the breakup of the liquid jet in crossflow. This simulation consists of models on liquid column, jet surface breakup, column fracture and secondary droplet breakup. These models have been embedded in the KIVA3-V code. We have calculated such parameters as the jet penetration, jet trajectory, droplet size, velocity field and the volume flux distribution. The results are compared with the experimental data in this paper.

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모델 램제트 연소기 내에서의 정상/가진 수직 분무 특성 연구 (An Investigation on the Spray Characteristics of Steady/Plused Jet in Crossflow in Model Ramjet Combustor)

  • 김진기;송진관;김민기;윤영빈;황용석
    • 한국분무공학회지
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    • 제13권2호
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    • pp.99-106
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    • 2008
  • In this study, spray characteristics research of steady/pulsed injection in crossflow was performed experimentally in the model ramjet combustor. High-speed-camera photography was performed through a visualization window of model combustor, and then, steady and pulsed spray structures were observed and analyzed. Varying influx air temperature and fuel species, we could obtain the trajectory correlation in the steady injection case. In the experiment of pulsed injection, it is found that the pulsed frequency hardly influences spray trajectory. Also, it is found that, in the same injection pressure differential, the trajectory correlation of steady condition can be used for estimating pulsed spray trajectory.

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평판 후류가 원통 표면의 물질전달에 미치는 영향에 대한 실험적 연구 (Experimental study on the effect of flat-plate wake on mass transfer about a cylinder in crossflow)

  • 맹두진;김형수;이준식
    • 대한기계학회논문집
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    • 제18권10호
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    • pp.2779-2786
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    • 1994
  • This study presents an experimental investigation of the effect of the wake on mass transfer about a circular cylinder in crossflow. The flat-plate wake was generated by merging two mirror images of turbulent boundary layers that were well developed along the both sides of flat plate with a sharp trailing edge. The velocity field was measured by a hot-wire system and the mass transfer rate by a naphthalene sublimation method. The mixing and developing stages of the wake were addressed to identify flow conditions. The mass transfer effects of different developing stages of the wake was discussed in detail. It is noted that a local maximum appears not at the front stagnation point but at a point a little downstream when the cylinder is located in the nearwake region and much more elevated mass transfer rate is obtained compared to effect of free-stream turbulence.

준 3차원 모델에 의한 주유동에 분사되는 난류제트 유동 해석 (Prediction of Turbulent Jet in a Crossflow by a Quasi Three Dimensional Model)

  • 맹주성;이종신
    • 대한기계학회논문집
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    • 제15권3호
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    • pp.954-962
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    • 1991
  • 본 연구에서는 횡 방향으로 속도구배를 타내는 a=.part.W/.part.z에 대한 방정식을 3차원 운동량 방정식으로 부터 유도한 준 3차원 수학적 모델을 성정하여 해석하였다. 또한 수치 해석을 위하여 Chen에 의하여 고안된 유한 해석법과 2-방정식 저 레이놀즈 K-.epsilon. 난류모델, 그리고 Maeng에 의해 제시된 경계 공정 좌표계를 사용하였다. 그리 고 프로그램의 검증을 위하여 G.Ber geles가 수행한 실험치와 비교하여 그 타당성을 입증하였다.

이차원 다중젯트의 유동 및 열전달 특성의 수치적 해석(II) -돌출열원이 있는 경우의 유동 및 열전달 특성- (A Numerical Analysis of Flow and Beat Transfer Characteristics of a Two-Dimensional Multi-Impingement Jet(II))

  • 장대철;이기명
    • Journal of Biosystems Engineering
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    • 제20권1호
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    • pp.66-72
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    • 1995
  • A numerical study for a two dimensional multi-impingement jet with crossflow of the spent fluid has been carried out. To study the flow characteristics especially in the jet flow region, three different distributions of mass flow rate at 5-jet exits were assumed. For each distribution, various Reynolds numbers ranging from laminar to turbulent flows were considered. Calculations drew the following items as conclusion. 1) A periodical fully developed flow was observed from the third protrusion. This was also observed from previous experimentally by Whidden at al. The Nessult number at the protrusion surface increased mildly as going downstream. 2) The low Reynolds number turbulence model of Launder and Sharma was found to be adequate for the prediction of fluid flow and heat transfer characteristics of two dimensional multi-jet configuration. 3) The Nusselt number at the protrusion surface was nearly proportional to the square root of the Reynolds number.

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Conceptual design of a copper-bonded steam generator for SFR and the development of its thermal-hydraulic analyzing code

  • Im, Sunghyuk;Jung, Yohan;Hong, Jonggan;Choi, Sun Rock
    • Nuclear Engineering and Technology
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    • 제54권6호
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    • pp.2262-2275
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    • 2022
  • The Korea Atomic Energy Research Institute (KAERI) studied the sodium-water reaction (SWR) minimized steam generator for the safety of the sodium-cooled fast reactor (SFR), and selected the copper bonded steam generator (CBSG) as the optimal concept. This paper introduces the conceptual design of the CBSG and the development of the CBSG sizing analyzer (CBSGSA). The CBSG consists of multiple heat transfer modules with a crossflow heat transfer configuration where sodium flows horizontally and water flows vertically. The heat transfer modules are stacked along a vertical direction to achieve the targeted large heat transfer capacity. The CBSGSA code was developed for the thermal-hydraulic analysis of the CBSG in a multi-pass crossflow heat transfer configuration. Finally, we conducted a preliminary sizing and rating analysis of the CBSG for the trans-uranium (TRU) core system using the CBSGSA code proposed by KAERI.