• 제목/요약/키워드: Inclined angle

검색결과 522건 처리시간 0.028초

초음파회절방법(超音波回折方法)을 이용한 귀렬(龜裂)의 높이 측정(測定) (Measurement of the Crack Height using the Two-Probe Ultrasonic Diffraction Method.)

  • 이재옥;이승규;김영길
    • 비파괴검사학회지
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    • 제7권2호
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    • pp.35-41
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    • 1988
  • The optimum test conditions of measuring the crack height were determined for the two-probe ultrasonic diffraction method. The applicability and the accuracy of the two-probe ultrasonic diffraction method on the inclined artificial cracks and the fatigue cracks were evaluated. It us possible to measure the height of the normal and inclined artificial cracks with the maximum error of ${\pm}\;0.5mm$ with the two-probe ultrasonic diffraction method. It was found, however, that the accuracy of this method in meaasuring the height of the fatigue crack depends on the degree of closure of the crack tip. It was desirable to choose a refraction angle as small as possible, but the angle should not be so small that the distortion of the lateral waveform became appreciable.

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경사진 벽부착 제트의 열전달 특성에 대한 연구 (An Investigation on Heat transfer Characteristics of Inclined Wall Attaching Offest jet)

  • 심재경
    • Journal of Advanced Marine Engineering and Technology
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    • 제22권2호
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    • pp.200-209
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    • 1998
  • Experiments have been conducted to determine heat transfer characteristics for a two-dimen-sional turbulent wall attaching offset jet at different oblique angles to a flat surface. The local Nusselt number distributions were measured using liquid crystal as a temperature sensor. Wall static pressure coefficient profiles were measured at the Reynolds number Re 53200(based on the nozzle width, D) the offset ratio H/D from 2.5 to 10 and the oblique angle a from $0^{\circ}$, to $40^{\circ}$ It is observed that the maximum Nusselt number point occurs slightly upstream of time-averaged reattachment point for all oblique angles. The correlations between the maximum Nusselt number and Reynolds number offset ration and oblique angle are presented.

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태양열시스템 설치를 위한 방위별 경사면일사량 분석 (Analysis of Solar Radiation on Inclined Surfaces with various Directions for the Installation of Solar Thermal Systems)

  • 조덕기;강용혁
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2008년도 추계학술대회 논문집
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    • pp.171-173
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    • 2008
  • The amount of incident solar rays on inclined surfaces with various directions has been widely utilized as important data in installing solar collector, hot water system, and designing solar buildings and house. This is because the performance of the solar energy applied systems is much affected by angle and direction of incident rays. Recognizing those factors mentioned above are of importance, actual experiment has been performed in this research to obtain the angle of inclination with which the maximum incident rays can be absorbed. The results obtained in this research could be used in designing optimal solar thermal systems.

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순수한 찬물속에 잠겨있는 경사진 등온벽면 부근의 자연대류에 관한 수동력학적 안정성 (The Hydrodynamic Stability of Natural Convection Flows Adjacent to an Inclined Isothermal Surface Submerged in Cold, Pure Water)

  • 황영규;장명륜
    • 설비공학논문집
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    • 제2권4호
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    • pp.268-278
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    • 1990
  • Hydrodynamic stability equations are formulated for natural convection flows adjacent to a heated or cooled, inclined, isothermal surface in pure water at $4^{\circ}C$, where the density variation with temperature becomes nonlinear. The resulting stability equations, when reduced to ordinary differential equations by a similarity transformation, constitute a two-point boundary-value problem, which was solved numerically. It is found from the obtained stability results that the neutral stability curves are systematically shifted to have lower critical Grashof numbers, as the inclination angle of upward-facing plate increases. Also, the nose of the neutral stability curve becomes blunter as the angle increases. It implies that the greater the inclination of the upward-facing plate, the more susceptible of the flow to instability for the wide range of disturbance wave number and frequency.

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경사진 바인더면의 드로우비드력을 측정하기 위한 모의실험장치 (An Angle-Binder Drawbead Simulator for Measuring Drawbead Forces on Inclined Binder Surface)

  • 양우호;최광용
    • 한국소성가공학회:학술대회논문집
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    • 한국소성가공학회 2009년도 춘계학술대회 논문집
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    • pp.180-184
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    • 2009
  • A novel set of experimental test tooling for measuring pulling and holding forces for drawbeads on binders inclined at a wide range of angles is introduced. A mechanical design featuring a single load cell, a male-female draw bead set, translation and rotation degrees of freedom, and a screw-driven clamping system has been incorporated into a standard tensile test machine. On a real time basis, restraining and holding force data with respect to draw-in displacement may be directly downloaded into a PC for data processing. The proposed experimental system represents a significant breakthrough in drawbead simulation technology due to its relatively low cost, clever design, and versatility. The system is shown to yield excellent experimental data suitable for verifying theory and numerical model predictions.

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방위별 경사면일사량 분석에 관한 연구 (A Study on the Analysis of Solar Radiation on Inclined Surfaces)

  • 조덕기;전일수;전명석;강용혁;오정무
    • 한국태양에너지학회 논문집
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    • 제21권3호
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    • pp.19-24
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    • 2001
  • The amount of incident solar rays on inclined surfaces with various directions has been widely utilized as important data in installing solar collector, hot water system, and photovoltaic module, and designing solar buildings and house. This is because the performance of the solar energy applied systems is much affected by angle and direction of incident rays. Recognizing those factors mentioned above are of importance, actual experiment has been peformed in this research to obtain the angle of inclination with which the maximum incident rays can be absorbed. The results obtained in this research could be used in designing optimal solar systems.

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프리캐스트 콘크리트 전단키의 역학적 거동에 관한 실험연구 (An Experimental Study on the Behavior of Precast Concrete Shear Keys)

  • 오병환;이준서;이형준;임동환
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1992년도 봄 학술발표회 논문집
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    • pp.86-89
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    • 1992
  • In the precast segmental method of construction, segments of a structure are precast, assembled, and tied together by post-tensioning to form the structure. Shear strength and behavior of points in precast concrete structures are important problems in the design of these structures. An experimental program was set up study the shear behavior of precast concrete shear keys. experimental models of keyed joints include a single key, representing one of a series include the shear key shape, d/h ratio(1/4, 1/5, 1/7), and inclined angle (45。 60。 75。). Two different types of joints, i.e., epoxied joint and dry joints were studied. From the present tests, it is found that epoxied joints have higher shear strength than those of dry joints, and that high d/h ratio keys have higher shear strength than those of low d/h ratio keys. The keys with 60。-inclined angle shows the highest shear strength among various angles.

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기울어진 정방형 실린더를 지나는 유동패턴의 수치해석적 연구 (NUMERICAL STUDY OF FLOW PATTERNS PAST AN INCLINED SQUARE CYLINDER)

  • 윤동혁;양경수;최춘범
    • 한국전산유체공학회지
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    • 제14권2호
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    • pp.19-24
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    • 2009
  • A parametric study has been carried out to elucidate the characteristics of flow past a square cylinder inclined with respect to the main flow for Re$\leq$150. Reynolds number and angle of incidence are the key parameters which determine the flow characteristics. This study would be the first step towards understanding flow pattern past a cylindrical structure under a strong gust of wind from the viewpoint of wind hazards. A complete classification of flow pattern has been obtained in the laminar region.

PV시스템 설치를 위한 경사면 태양광에너지 분석에 관한 연구 (A Study on the Analysis of Solar Radiation on Inclined Surfaces for the Installation of PV Systems)

  • 조덕기;강용혁
    • 한국태양에너지학회 논문집
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    • 제27권1호
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    • pp.11-17
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    • 2007
  • The amount of incident rays over inclination according to direction has been widely utilized as important data in installing photovoltaic systems. This is because the performance of the photovoltaic systems in much affected by angle and direction of incident rays. Recognizing that factors mentioned above are of importance, actual experiment on the moving route of the sun have been performed in this research to obtain the angle of inclination with which the maximum incident rays can be absorbed. After all, the standard for designing highly optimized photovoltaic systems will be provided for designers and employees working in the photovoltaic module related industries.

VARIATION OF LOCAL POOL BOILING HEAT TRANSFER COEFFICIENT ON 3-DEGREE INCLINED TUBE SURFACE

  • Kang, Myeong-Gie
    • Nuclear Engineering and Technology
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    • 제45권7호
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    • pp.911-920
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    • 2013
  • Experimental studies on both subcooled and saturated pool boiling of water were performed to obtain local heat transfer coefficients on a $3^{\circ}$ inclined tube of 50.8 mm diameter at atmospheric pressure. The local values were determined at every $45^{\circ}$ from the very bottom to the uppermost of the tube periphery. The maximum and minimum local coefficients were observed at the azimuthal angles of $0^{\circ}$ and $180^{\circ}$, respectively, in saturated water. The locations of the maxima and the minima were dependent on the inclination angle of the tube as well as the degree of subcooling. The major heat transfer mechanisms were considered to be liquid agitation generated by the sliding bubbles and the creation of big size bubbles through bubble coalescence. As a way of quantifying the heat transfer coefficients, an empirical correlation was suggested.