• 제목/요약/키워드: Assembly Structure

검색결과 810건 처리시간 0.031초

Thermal-fluid-structure coupling analysis for plate-type fuel assembly under irradiation. Part-I numerical methodology

  • Li, Yuanming;Yuan, Pan;Ren, Quan-yao;Su, Guanghui;Yu, Hongxing;Wang, Haoyu;Zheng, Meiyin;Wu, Yingwei;Ding, Shurong
    • Nuclear Engineering and Technology
    • /
    • 제53권5호
    • /
    • pp.1540-1555
    • /
    • 2021
  • The plate-type fuel assembly adopted in nuclear research reactor suffers from complicated effect induced by non-uniform irradiation, which might affect its stress conditions, mechanical behavior and thermal-hydraulic performance. A reliable numerical method is of great importance to reveal the complex evolution of mechanical deformation, flow redistribution and temperature field for the plate-type fuel assembly under non-uniform irradiation. This paper is the first part of a two-part study developing the numerical methodology for the thermal-fluid-structure coupling behaviors of plate-type fuel assembly under irradiation. In this paper, the thermal-fluid-structure coupling methodology has been developed for plate-type fuel assembly under non-uniform irradiation condition by exchanging thermal-hydraulic and mechanical deformation parameters between Finite Element Model (FEM) software and Computational Fluid Dynamic (CFD) software with Mesh-based parallel Code Coupling Interface (MpCCI), which has been validated with experimental results. Based on the established methodology, the effects of non-uniform irradiation and fluid were discussed, which demonstrated that the maximum mechanical deformation with irradiation was dozens of times larger than that without irradiation and the hydraulic load on fuel plates due to differential pressure played a dominant role in the mechanical deformation.

Thermal-fluid-structure coupling analysis on plate-type fuel assembly under irradiation. Part-II Mechanical deformation and thermal-hydraulic characteristics

  • Li, Yuanming;Ren, Quan-yao;Yuan, Pan;Su, Guanghui;Yu, Hongxing;Zheng, Meiyin;Wang, Haoyu;Wu, Yingwei;Ding, Shurong
    • Nuclear Engineering and Technology
    • /
    • 제53권5호
    • /
    • pp.1556-1568
    • /
    • 2021
  • The plate-type fuel assembly adopted in nuclear research reactor suffers from complicated effect induced by non-uniform irradiation, which might affect stress conditions, mechanical behaviors and thermal-hydraulic performance of the fuel assembly. This paper is the Part II work of a two-part study devoted to analyzing the complex unique mechanical deformation and thermal-hydraulic characteristics for the typical plate-type fuel assembly under irradiation effect, which is on the basis of developed and verified numerical thermal-fluid-structure coupling methodology under irradiation in Part I of this work. The mechanical deformation, thermal-hydraulic performance and Mises stress have been analyzed for the typical plate-type fuel assembly consisting of support plates under non-uniform irradiation. It was interesting to observe that: the plate-type fuel assembly including the fuel plates and support plates tended to bend towards the location with maximum fission rate; the hot spots in the fuel foil appeared at the location with maximum thickness increment; the maximum Mises stress of fuel foil was located at the adjacent location with the maximum plate thickness increment et al.

3차원 퍼즐 시스템을 위한 구조물 조립 기법 (Structure Assembling Method for 3D Puzzle System)

  • 김진모;조형제
    • 한국멀티미디어학회논문지
    • /
    • 제12권1호
    • /
    • pp.58-68
    • /
    • 2009
  • 컴퓨터 하드웨어의 급격한 발전과 다양한 게임 기술의 발전으로 인해 게임 품질이 향상되고 게임 장르도 다변화 되었다. 이에 비해 퍼즐게임은 기존의 단순한 게임방식을 고수함으로 인해 점점 위축되고 있다. 따라서 본 연구는 현재 퍼즐게임의 한계를 벗어날 돌파구를 3차원 퍼즐게임에서 모색하려는 첫 시도이다. 3차원 퍼즐게임에서의 사실적인 퍼즐 조립을 표현하기 위해 조립에 적합한 구조물 처리 과정과 객체간의 정교한 충돌 방법, 물리구조를 활용한 3단계로 구성된 구조물 조립 기법을 설계하고 이를 통해 조립과정에서 연산 비용을 최소화하면서도 구조물 간의 정교한 퍼즐 조립이 가능함을 간단한 실험으로 보인다.

  • PDF

Prediction of the welding distortion of large steel structure with mechanical restraint using equivalent load methods

  • Park, Jeong-ung;An, Gyubaek
    • International Journal of Naval Architecture and Ocean Engineering
    • /
    • 제9권3호
    • /
    • pp.315-325
    • /
    • 2017
  • The design dimension may not be satisfactory at the final stage due to the welding during the assembly stage, leading to cutting or adding the components in large structure constructions. The productivity is depend on accuracy of the welding quality especially at assembly stage. Therefore, it is of utmost importance to decide the component dimension during each assembly stage considering the above situations during the designing stage by exactly predicting welding deformation before the welding is done. Further, if the system that predicts whether welding deformation is equipped, it is possible to take measures to reduce deformation through FE analysis, helping in saving time for correcting work by arresting the parts which are prone to having welding deformation. For the FE analysis to predict the deformation of a large steel structure, calculation time, modeling, constraints in each assembly stage and critical welding length have to be considered. In case of fillet welding deformation, around 300 mm is sufficient as a critical welding length of the specimen as proposed by the existing researches. However, the critical length in case of butt welding is around 1000 mm, which is far longer than that suggested in the existing researches. For the external constraint, which occurs as the geometry of structure is changed according to the assembly stage, constraint factor is drawn from the elastic FE analysis and test results, and the magnitude of equivalent force according to constraint is decided. The comparison study for the elastic FE analysis result and measurement for the large steel structure based on the above results reveals that the analysis results are in the range of 80-118% against measurement values, both matching each other well. Further, the deformation of fillet welding in the main plate among the total block occupies 66-89%, making welding deformation in the main plate far larger than the welding deformation in the longitudinal and transverse girders.

경수로 원전연료용 지지격자체의 LASER 용접부위 평가 (Welding Quality Evaluation on the LASER Welding Parts of the Spacer Grid Assembly for PWR Fuel Assembly)

  • 송기남;윤경호;강흥석;이강희;김수성
    • 대한용접접합학회:학술대회논문집
    • /
    • 대한용접접합학회 2004년도 추계학술발표대회 개요집
    • /
    • pp.67-69
    • /
    • 2004
  • The fuel assemblies as the nuclear fuel for the pressurized water reactor(PWR) are loaded in the reactor core throughout the residence time of three to five years. The spacer grid assembly, which is an interconnected array of slotted grid straps and is welded at the intersections to form an egg crate structure, is one of the main structural components of the fuel assembly. The spacer grid assembly is structurally required to have enough buckling strength under various kinds of lateral load acting on the fuel assembly so as to keep the fuel assembly straight. To meet the requirement, integrity on the spacer grid welding parts should be carefully checked. In this study, welding quality of the spacer grid assembly welded by several welding companies are examined and compared.

  • PDF

조립 및 분리용이성을 고려한 컴퓨터 케이스 재설계 (Redesign for Ease of Assembly and Disassembly in Computer case)

  • 이정우;김인호
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2000년도 추계학술대회 논문집
    • /
    • pp.344-347
    • /
    • 2000
  • In this paper, a redesign of computer case is proposed by applying some guide lines of assembly and disassembly to an existing computer case. Some problems such as increase of number of disassembly and vibration, difficult assembly and disassembly from unfittable covers are recognized through analysis of geometrical structure and practical assembly and disassembly. A solution of these problems is proposed through ideas of ease of assembly and disassembly. Design for Environment Software is used to evaluate both redesigned and existing products. Time of assembly and disassembly and MET-point are especially calculated by the software, and these data give us a good guide for analysis of ease of assembly, ease of disassembly and environmental influence in both products.

  • PDF

경수로 원전연료용 질칼로이 지지격자체의 LASER 용접품질 평가(III) (Welding Quality Evaluation on the LASER Welding Parts of the Zircaloy Spacer Grid Assembly for PWR Fuel Assembly(III))

  • 송기남;윤경호;이강희;김수성;한형준
    • 대한용접접합학회:학술대회논문집
    • /
    • 대한용접접합학회 2006년도 춘계 학술대회 개요집
    • /
    • pp.42-44
    • /
    • 2006
  • A spacer grid assembly, which is an interconnected array of slotted grid straps and is welded at the intersections to form an egg crate structure, is one of the main structural components of the nuclear fuel assembly for pressurized water reactors(PWRs). The spacer grid assembly is structurally required to have enough buckling strength under various kinds of lateral loads acting on the nuclear fuel assembly so as to keep the nuclear fuel assembly straight. To meet this requirement, it is necessary to weld the welding parts carefully and precisely. In this study, a series of welding tests were carried out to find an optimum welding condition. After examining and analyzing the specimens welded from the welding conditions, a recommendable laser welding condition was selected for the KAERI designed Zircaloy spacer grid assembly.

  • PDF

경수로 원전연료용 지지격자의 LASER 용접품질 평가 (Welding Quality Evaluation on the LASER Welding Parts of the Spacer Grid Assembly for PWR fuel Assembly)

  • 송기남;윤정호;강홍석;이강희;김우곤;김수성
    • 대한용접접합학회:학술대회논문집
    • /
    • 대한용접접합학회 2005년도 춘계학술발표대회 개요집
    • /
    • pp.109-111
    • /
    • 2005
  • Nuclear fuel assemblies for pressurized water reactors(PWR) are loaded in the reactor core throughout the residence time of three to five years. A spacer grid assembly, which is an interconnected array of slotted grid straps and is welded at the intersections to form an egg crate structure, is one of the main structural components of the nuclear fuel assembly. The spacer grid assembly is structurally required to have enough buckling strength under various kinds of lateral loads acting on the nuclear fuel assembly so as to keep the nuclear fuel assembly straight. To meet this requirement, it is necessary to weld the welding parts carefully and precisely. In this study, laser welding qualities of the spacer grid assembly welded by several welding companies, such as weld strength, weld penetration depth, and weld bead size, are examined and compared.

  • PDF

PDM기반 조립체 DMU를 위한 웹뷰어 형상커널의 설계 (Geometric Kernel Design of the Web-Viewer for the PDM Based Assembly DMU)

  • 송인호;정성종
    • 대한기계학회논문집A
    • /
    • 제31권2호
    • /
    • pp.260-268
    • /
    • 2007
  • Demand for the use of 3D CAD DMU systems over the Internet environment has been increased. However, transmission of commercial 3D kernels has delayed the communication effectiveness due to the kernel size. Light weight CAD geometric kernel design methodology is required for rapid transmission in the distributed environment. In this paper, an assembly data structure suitable for the top-down and bottom-up assembly models has been constructed. Part features are stored without a hierarchy so that they are created and saved in no particular order. In particular, this paper proposes a new assembly representation model, called multi-level assembly representation (MAR), for the PDM based assembly DMU system. Since the geometric kernel retains assembly hierarchy and topological information, it is applied to the web-viewer for the PDM based DMU system. Effectiveness of the proposed geometric kernel is confirmed through various case studies.

캠코더용 Iris Assembly의 국산화 및 생산 기술 개발 사례 (A Study of Development and Product ion Technology for Camcoder Iris Assembly)

  • 고종선
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1996년도 하계학술대회 논문집 A
    • /
    • pp.250-252
    • /
    • 1996
  • In this paper, the principle of operation. the part characteristic, characteristic of component movement, analysis are carried out for camcoder iris assembly which is one of the important element component in Video large projection TV instrument, and some Know-how for development of element component is also included. The magnetic field circuit for the small and simple structure with low power consumption is introduced and new materials of yoke for small motor system is suggested. Especially, the relation with remained magnetic field and operation duration time is analyzed by experimental results. Some problems of nonlinear torque characteristics include to obtain the simple and low cost structure in domestic production of element component is analyzed. Furthermore, development procedure is suggested for iris assembly and some methods to reduce the burr with some check points for small precise accessories are explained.

  • PDF