• 제목/요약/키워드: convergence section

검색결과 490건 처리시간 0.026초

Cone Type 밸브 내부유동 수치해석에 관한 연구 (A Study on the Numerical Analysis of Internal Flow in a Cone Type Valve)

  • 진도훈
    • 한국산업융합학회 논문집
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    • 제23권2_2호
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    • pp.199-207
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    • 2020
  • These days, many different types of valves are developed in the industrial area according to their use purpose. Multiple kinds of valves are installed to control a flow and pressure of the pipe conveying fluid. Valves serve as critical roles in land plants such as power plants. The performance of equipment varies depending on valve characteristics. In this study, the internal flow analysis on Cone-type valve is conducted to analyze flow field and secure a value of the flow coefficient Cv. According to the internal flow analysis, when the flow distribution of the middle cross-section of valve was open 100%, flow field was relatively and smoothly taken out. If it was open 50%, flow recirculation region increased and a little complex flow field occurred. Unlike ball valve or butterfly valve, this valve had flow recirculation in its outlet depending on a valve opening amount. Therefore, it was found that there was no flow recirculation in the outlet of Cone-type valve.

STL 포맷의 단면정보를 이용한 형상분할에 관한 연구 (A Study on Feature Division using Sliced Information of STL Format)

  • 반갑수
    • 한국산업융합학회 논문집
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    • 제5권2호
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    • pp.141-146
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    • 2002
  • Stereolithography is the best known as rapid prototyping system. It uses the STL format data which is generated from CAD system. In this study, One of the main function of this developed CAM system deals with shape modification which divide a shape into two parts or more. The cross section of a STL part by a z-level is composed with nested or single polygonal closed loop. In order to make RP product, closed loops must fill with triangular facets from SSET and recover sliced triangular facets which is located normal direction to the cross sectional plane. The system is development by using Visuall C++ compiler in the environment of pentium PC. Operating system is Windows NT workstaion from Micro-Soft.

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SFRC구조물의 휨거동에 관한 해석적 연구 (Analytical Study of Flexural Behavior on Steel Fiber Reinforced Concrete Structure)

  • 서성탁
    • 한국산업융합학회 논문집
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    • 제11권1호
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    • pp.35-40
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    • 2008
  • Various characters of the concrete are greatly improved as the effect of the steel fiber. As the improvement effect of the steel fiber, the increment in flexural strength, shear strength, toughness, and impact strength are remarkable, and tenacious concrete is obtained. This paper presents model which can predict mechanical behavior of the structure according to aspect ratio and volume fraction of steel fiber. Experiments on compressive strength, elastic modulus and tensile strength were performed with self-made cylindrical specimens of variable aspect ratios. This paper presents an analytical study on the behavior of a beam specimen with steel fiber reinforced concrete(SFRC). The effect of the SFRC on the crack pattern, failure mode and the flexural behavior of the structure were investigated. The analysis model based on the nonlinear layered finite element method was successfully able to find the necessary amount of steel fibers, tensile steels and beam section which can best approximate flexural strength and ductility of a given conventionally reinforced concrete beam.

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비접촉 이송 시스템의 구동원으로서 동전기 휠의 응용 (Application of the electrodynamic wheel as a driving principle of noncontact transfer system)

  • 정광석
    • 융복합기술연구소 논문집
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    • 제6권2호
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    • pp.1-7
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    • 2016
  • The rotating electrodynamic wheels can produce three-axial forces on the conductive target. The forces are linked strongly each other, and their magnitudes depend on the rotating speed of the wheel. However, the wheels can be used effectively as an actuating principle for transfer system of conductive material. The conductive material is a pipe with a constant cross-section or a conductive plate. In this paper, a few applications using the electrodynamic wheels as transferring means are introduced including the full description of the real hardware implementation.

SI 열화학 수소 생산 공정의 분석을 위한 열역학 모델의 적용 (Application of Thermodynamic Models for Analysis on SI Thermochemical Hydrogen Production Process)

  • 이준규;김기섭;박병흥
    • 융복합기술연구소 논문집
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    • 제2권2호
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    • pp.30-34
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    • 2012
  • The SI thermochemical cycle process accomplishes water splitting through distinctive three chemical reactions. We focused on thermodynamic models applicable to the process. Recently, remarkable models based on the assumed ionic species have been developed to describe highly nonideal behavior on the liquid phase reactions. ElecNRTL models with ionic reactions were proposed in order to provide reliable process simulation results for phase equilibrium calculations in Section II and III. In this study, the current thermodynamic models of SI thermochemical cycle process were briefly described and the calculation results of the applied ElecNRTL models for phase equilibrium calculations were illustrated for binary systems.

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감온액정을 이용한 층류유동의 온도장에 관한 실험적 연구 (An Experimental Study on Laminar Flow Temperature Using Thermo-sensitive Liquid Crystal)

  • 장태현
    • 한국산업융합학회 논문집
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    • 제6권4호
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    • pp.373-378
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    • 2003
  • An experimental investigation was performed to study the characteristics of laminar water flow in a horizontal circular tube by using liquid crystal. A simultaneous measurement technique has been employed to measure the temperature field in a two-dimensional cross section of fluid flow. This study found the temperature distribution for Re =900~1,500 along longitudinal sections and the results appear to be physically reasonable. To determine some characteristics of the laminar flow, 2D PIV technique is employed for temperature measurement and liquid crystal is used for heat transfer experiments in water. The experimental rig was manufactured from an acryle tube. The test tube diameter of 25mm, and a length of 1200mm. The used algorithm is the gray level cross-correlation method by using Kimura et al. in 1986.

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영역분할에 의한 격자세분화 기법 및 압출공정의 유한요소해석에의 적용 (Mismatching Refinement with Domain Decomposition and Its Application to the Finite Element Analysis of the Extrusion Process)

  • 박근;양동열
    • 소성∙가공
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    • 제8권3호
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    • pp.284-293
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    • 1999
  • The rigid-plastic finite element analysis requires a large amount of computation time due to its non-linearity. For economic computation, mismatching refinement, and efficient domain decomposition method with different mesh density for each sub domain, is developed. A modified velocity alternating scheme for the interface treatment is proposed in order to obtain good convergence and accuracy. As a numerical example, the axisymmetric extrusion process is analyzed. The results are discussed for the various velocity update schemes form the viewpoint of convergence and accuracy. The three-dimen-sional extrusion process with rectangular section is analyzed in order to verify the effectiveness of the proposed method. Comparing the results with those of the conventional method of full region analysis, the accuracy and the computational efficiency of the proposed method are then discussed.

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감온액정을 이용한 층류유동의 속도장에 관한 실험적 연구 (An Experimental Study on Laminar Flow Velocity by Using Thermo-sensitive Liquid Crystal)

  • 장태현
    • 한국산업융합학회 논문집
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    • 제7권1호
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    • pp.19-24
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    • 2004
  • An experimental investigation was performed to study the characteristics of laminar water flow in a horizontal circular tube by using liquid crystal. A simultaneous measurement technique has been employed to measure the velocity field in a two-dimensional cross section of fluid flow. This study found the velocity distributions for Re = 1,594 ~ 2,510 along longitudinal sections and the results appear to be physically reasonable. To determine some characteristics of the laminar flow, 2D PIV technique is employed for velocity measurement by using liquid crystal in water. The experimental rig was manufactured from an acryle tube. The test tube diameter of 25mm, and a length of 1200mm. The used algorithm is the gray level cross-correlation method by using Kimura et al. in 1986.

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열전소자를 이용한 고온용 로봇 그리퍼 냉각장치에 관한 연구 (Study of the robot gripper cooling device for a high temperature material using peltier element)

  • 신기수;홍성덕;김근수;권순재
    • 한국산업융합학회 논문집
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    • 제18권1호
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    • pp.37-44
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    • 2015
  • In the research, we developed a device for cooling the drive section of the gripper of a robot for handling the high temperature material. In this study, By using a Peltier element, the high-temperature material is not affected and driving cylinder is cooled to prevent damage due to high temperatures. Hot part of the Peltier element is towards the robot gripper. Cool part of the Peltier element is towards the driving cylinder. The heat sink portion is made to keep the cooling effect. As the performance result, cooling-test is taken, and their result is satisfy.

블록단위 영역분할을 이용한 얼굴 특징 요소 추출 (Extraction of Facial Feature Component using Section Segmentation of Block-units)

  • 김승업;이우범;김욱현
    • 융합신호처리학회 학술대회논문집
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    • 한국신호처리시스템학회 2000년도 추계종합학술대회논문집
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    • pp.97-100
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    • 2000
  • 본 논문에서는 얼굴의 특징 추출 알고리즘을 제안한다. 입력 영상을 이진 영상으로 처리한 후, 얼굴 요소 후보 블록의 면적, 둘레, 원형도, 종횡비를 이용하여 불변하는 눈, 코, 입의 특징 요소를 추출한다. 사람의 얼굴에 대한 특징 요소를 추출하기 위하여 우선 이진 영상을 생성한다. 하나 하나의 고립된 영역으로 분리하기 위하여 화소 레이블링을 한 후 만들어진 얼굴 요소 후보 블록 단위로 면적을 구하고, 윤곽선 추적 방법에 의하여 둘레를 구한 다음 면적, 둘레, 원형도 및 종횡비의 유사도를 구한다 블록의 종합 유사도, 대칭적 거리, 위치의 유사도를 활용하여 눈, 코, 입을 추출한다. 추출된 각 특징 요소간의 거리와 각도를 이용하여 12개의 특징 인수를 구하는 제안 알고리즘을 수행함으로써 얼굴의 특징 인수들을 추출한다. 각 특징점 사이의 거리와 각 거리간의 기울기를 이용하여 100명으로부터 획득한 297개의 원 영상을 대상으로 12개의 특징 파라미터를 추출한 결과 92.93%의 추출 성공률을 보였다. 이러한 결과는 외부 환경의 영향을 덜 받는 눈, 코, 입의 위치 관계의 블록을 근거로 특징 요소를 추출할 수 있도록 제안 알고리즘을 구성하였던 것으로 판단된다.

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