• 제목/요약/키워드: Marine structural element

검색결과 182건 처리시간 0.034초

유한요소 해석을 이용한 선박용 엔진 프레임 박스 용접부의 피로수명 예측 (Fatigue Life Estimation for Welded Parts of Marine Vessel Engine Frame Box by Utilizing Finite Element Analysis)

  • 이재훈;최종호;조진래;이인수
    • 한국전산구조공학회논문집
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    • 제20권5호
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    • pp.573-580
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    • 2007
  • 본 논문은 선박용 엔진인 S60MC-C의 프레임 박스 용접부에 대한 피로수명 예측을 위한 수치적 기법을 제시한다. 피로 수명 평가를 위해 싸이클 동안의 동적인 응력변화를 계산해내야 하며, 이에 따라 선행된 연구에서 얻은 엔진의 한 싸이클 동안의 하중 조건으로 상용 유한요소해석 프로그램을 이용한 구조해석을 실시하였다. 구조해석은 8단계에 대해 이루어 졌으며, 그 결과를 바탕으로 프레임 박스 용접부의 피로수명 평가를 위해서 HSS(Hot spot stress), Reservoir counting method, Palmgren-miner's rule을 적용하였다. 결과적으로 구조해석을 통한 대상 엔진의 취약부와 과잉 설계부를 확인하였고, 피로수명의 평가를 통해 설계의 적절성 여부를 평가하였다.

ISO 기반 Moon Pool형 다이버 보트 구조 건전성 평가 (Evaluation of Structural Integrity of the ISO-based Moon Pool Type Diver Boats)

  • 강병모;오우준;나현호;최주석
    • 해양환경안전학회지
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    • 제24권5호
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    • pp.597-603
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    • 2018
  • 본 연구는 수중 및 여가활동에 대한 수요 증가에 따른 다이버들을 위한 보트의 구조 건전성에 관한 것이다. 대상 선박은 선체 중앙부에 Moon Pool 구조를 갖추고 있는 소형 쌍동선이며, 연구수행은 ISO Rule 기반의 허용응력 산정을 통한 유한요소 해석법을 이용하여 연구를 수행하였다. 연구수행 방법은 ISO 12215-5와 TC118.1225-7에서 정의하고 있는 계수를 산정하고, 종방향굽힘 모멘트, 비틀림 모멘트, 선저슬래밍 하중 등을 적용하여 ISO 기준과 허용응력 설계법(ASD)에 의한 적합성 여부를 판정하고 유한요소해석(FEA)를 활용한 극한강도 설계법을(LFRD)를 적용하여 수행하였다. 연구결과 문풀형 구조를 가진 선박도 ISO규정, KR규정을 적용하여 설계시 구조적 건전성을 확보하는 것으로 사료된다.

Topology Optimization of the Decking Unit in the Aluminum Bass Boat and Strength Verification using the FEM-program

  • Seo, Kwang-Cheol;Gwak, Jin;Park, Joo-Shin
    • 해양환경안전학회지
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    • 제24권3호
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    • pp.367-372
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    • 2018
  • The objective of this paper is to optimize the cross-section of aluminum decking units used in the bass boats under operating conditions, and to verify the optimized model from the results via by ANSYS software. Aluminum decking unit is needed to endure specific loading while leisure activity and sailing. For a stiffer and more cost-neutral aluminum decking unit, optimization is often considered in the naval and marine industries. This optimization of the aluminum decking unit is performed using the ANSYS program, which is based on the topology optimization method. The generation of finite element models and stress evaluations are conducted using the ANSYS Multiphysics module, which is based on the Finite Element Method (FEM). Through such a series of studies, it was possible to determine the most suitable case for satisfying the structural strength found among the phase-optimized aluminum deck units in bass boats. From these optimization results, CASE 1 shows the best solution in comparison with the other cases for this optimization. By linking the topology optimization with the structural strength analysis, the optimal solution can be found in a relatively short amount of time, and these procedures are expected to be applicable to many fields of engineering.

Study on Stiffened-Plate Structure Response in Marine Nuclear Reactor Operation Environment

  • Han Koo Jeong;Soo Hyoung Kim;Seon Pyoung Hwang
    • 한국해양공학회지
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    • 제37권5호
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    • pp.205-214
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    • 2023
  • As the regulations on greenhouse gas emissions at sea become strict, efforts are being made to minimize environmental pollutants emitted from fossil fuels used by ships. Considering the large sizes of ships in conjunction with securing stable supplies of environment-friendly energy, interest in nuclear energy to power ships has been increasing. In this study, the neutron irradiation that occurs during the nuclear reactor operation and its effect on the structural responses of the stiffened-plate structures are investigated. This is done by changing the material properties of DH36 steel according to the research findings on the neutron-irradiated steels and then performing the structural response analyses of the structures using analytical and finite-element numerical solutions. Results reveal the influence of neutron irradiation on the structural responses of the structures. It is shown that both the strength and stiffness of the structures are affected by the neutron-irradiation phenomenon as their maximum flexural stress and deflection are increased with the increase in the amount of neutron irradiation. This implies that strength and stiffness need to be considered in the design of ships equipped with marine nuclear reactors.

응력 특이점을 갖는 필릿 용접구조물의 피로해석을 위한 가상절점법을 이용한 구조응력 계산 기법 고찰 (A Study on the Fatigue Strength Evaluation for Fillet Weldment including Stress Singularity using Structural Stress with Virtual Node Method)

  • 하청인;강성원;김명현;김만수;손상용;허주호
    • Journal of Welding and Joining
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    • 제24권3호
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    • pp.27-33
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    • 2006
  • Structural stress approach is well known as a mesh-size insensitive fatigue assessment method by using finite element analyses. It is, however, difficult to estimate the structural stress (SS) at weld end points due to stress singularities when shell elements are used. In this study, fatigue evaluations with longitudinal load carrying box fillet weldment under out-of-plane bending load have been performed by using virtual node method (VNM) in order to avoid the problem, which is called the weld end effect. Various combinations of virtual node parameters, such as reference point and virtual node locations, are investigated for the estimation of proper structural stress values applying VNM in a systematic manner. The appropriate guidance of virtual node parameter has been offered for the fillet weldment considered in the study. The structural stress values obtained by VNM have also been validated by comparing the result with finite element model including weld bead. Moreover, the fatigue strength of the fillet weldment based on the equivalent structural stress is shown to be consistent with the master S-N curve.

객체지향개념을 이용한 유한요소 구조설계 시스템 개발 (Development of Finite Element Structural Design System using Object-Oriented Concept)

  • 이상갑;장승조
    • 해양환경안전학회지
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    • 제1권2호
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    • pp.83-94
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    • 1995
  • The purpose of this paper is to develop an integrated environment system for finite element structural analysis using OOA(Object-Oriented Analysis) and OOD(Object-Oriented Design), with may reduce inconveniencies in use such as file input of macro command and improve lacks of graphic presentation in the established finite element analysis program. This paper is attempted to suggest an easy approach to object-oriented concept and convenient programming. Two languages are used together in this paper instead of single C++ language for the development of object-oriented program. : Visual Basic with CDK(Custom Development Kit), and Borland C++ with OWL(Object Windows Library).

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선박 유압공급 장치용 사판식 유압 피스톤 펌프의 구조적 안정성에 관한 연구 (A Study on the Structural Stability of the Swash Plate Piston Pump for Marine Hydraulic Power Supply)

  • 곽범섭;임종학;이인욱;이중섭;이호성;송철기
    • 한국기계가공학회지
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    • 제20권4호
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    • pp.24-30
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    • 2021
  • In this paper, a structural stability analysis of the swash plate hydraulic piston pump installed on hydraulic supply systems in marine vessels is presented. In order to verify the integrity of the pump design, a standard structural analysis technique based on the finite element method has been applied for various operating and boundary conditions. For the maximum operational torque (223 N·m) at 5°, 10°, and 15° of the swash plate angle, the maximum deformation, equivalent stress and safety factor are evaluated. The analytical results show that under current operating conditions, the structural reliability of the design has been confirmed.

박용엔진 실린더 커버 스터드의 구조거동 분석 (Structural Behavior of the Cylinder Cover Stud of Marine Diesel Engine)

  • 김병주;이재옥;박진수;김세락
    • 한국마린엔지니어링학회:학술대회논문집
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    • 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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    • pp.267-268
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    • 2006
  • The cylinder cover stud of low-speed marine diesel engine is more than just a stud. It is a large structural element occasionally weighing over 200 kg used for assembling the combustion chamber components. Therefore, to understand the structural behavior of the stud and design it safely is quite important considering a catastrophic failure which can be arisen from an inadequate use of it. In this paper, the analysis results of the structural behavior of the stud is introduced. Strain measurement results compared with FE analysis results are summarized. The results showed that 1) the stud stress increased with engine operating load, 2) the maximum stress amplitude was about 10 MPa which is far smaller than the stud's fatigue strength of 61 MPa, 3) the stress ratio is higher than 0.9 and the stud's load factor is about 20 %, and 4) about 7 % of initial pressure tightening load was reduced while changing to a nut tightened condition.

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소형 요트의 기본 구조 설계 및 구조 해석 기법에 대한 연구 (A Study on the Structural Design and Structural Analysis for Small Yacht)

  • 신종계;이재열;이장현;반석호;이상홍;유재훈
    • 대한조선학회논문집
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    • 제43권1호
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    • pp.75-86
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    • 2006
  • The scantling and structural design work is done during the initial stage in yacht design. This paper studies a procedure of the structural design for yacht with an illustrative design. Scantling of structural members and loads are defined based on the rules suggested by ISO(International Standard Organization) and ABS(American Bureau of Shipping). Also, FEA(Finite Element Analysis) model is presented for a practical guide for structural analysis. An equivalent structural element is used to simplify the composite material for the analysis.

유한요소-전달강성계수법에 의한 이산계 곡선보의 자유진동해석 (Free Vibration Analysis of Curved Beams Regarded as Discrete System Using Finite Element-Transfer Stiffness Coefficient Method)

  • 최명수;여동준
    • 동력기계공학회지
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    • 제21권1호
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    • pp.37-42
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    • 2017
  • A curved beam is one of the basic and important structural elements in structural design. In this paper, the authors formulated the computational algorithm for analyzing the free vibration of curved beams using the finite element-transfer stiffness coefficient method. The concept of the finite element-transfer stiffness coefficient method is the combination of the modeling technique of the finite element method and the transfer technique of the transfer stiffness coefficient method. And, we confirm the effectiveness the finite element-transfer stiffness coefficient method from the free vibration analysis of two numerical models which are a semicircle beam and a quarter circle beam.