• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.631-634
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• 2011

본 연구에서는 규칙 파랑 중에 있는 부유식 구조물의 유탄성 거동을 해석 하고, 수치모델의 수렴성을 살펴본다. 부유식 구조물은 보로 모델링 하며, 유체는 이상유체로 가정하여 문제를 해결한다. 보 모델의 경우 Euler-Bernoulli 보 모델과 Timoshenko 보 모델로 나누어 그 특성을 비교 해 본다. 문제의 해석법에 있어서 부유식 구조물의 경우는 유한요소법을, 유체의 경우는 경계요소법을 이용하여, 상호 연성된 방정식을 이끌어 낸다. 상호 연성된 방정식을 토대로 Euler-Bernoulli 보 모델과 Timoshenko 보 모델의 거동 특성을 살펴보고 제시된 수치 모델을 기준으로 수렴성을 분석해 본다.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.23 no.12
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• pp.1035-1044
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• 2013

Because of the high specific stiffness and strength inherent in the sandwich structure composed of facesheet that resists in-plane loads and a core that resists out-of-plane loads, it is often used for large and light-weighted structures. However, inevitably the increased flexibility allows greater deformation-based disturbances in the structures. Thus, it is necessary to analyze the structural safety. To obtain more accurate analytical results, the input disturbances must more closely simulate real load conditions; to improve accuracy, non-linear elements such as gust effects were considered. In addition, the structural safety was analyzed for the iso-grid sandwich panel structure using fluid-structure interactions. For a more realistic simulation, flow velocity fields, which consider the effects of irregular gust fluctuation, were generated and the coupled field was analyzed by mapping the pressure and displacement.

• Computational Structural Engineering
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• v.32 no.3
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• pp.4-8
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• 2019

• Journal of the Society of Naval Architects of Korea
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• v.29 no.1
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• pp.135-142
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• 1992

In the vibration analysis or submerged of floating bodies such as ship and offshore structures, the coupled system between structure and fluid satisfying the compatibility conditions on the wetted surface should be considered. It is well known that the hydroelastic analysis of structural vibration in contact with fluid can be solved by applying the finite element method to structure and the boundary element method to fluid domain. However such an approach is impractical, because fluid added mass matrix is fully coupled on whole wetted surface. To overcome this shortcoming, an efficient approach based on reanalysis scheme is proposed in this paper. The proposed method can be applied for cases with higher modes lacking 3-D reduction factor J as well as beam-like modes of marine structures. It is well known the traditional method using 2-D added mass and J-factor is good only for beam-like modes with reliable J values. The validity and the calculation efficiency of the proposed method are proved with numerical examples.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.203-208
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• 2011

본 논문에서는 해양시추 생산설비의 상부구조(topside structure)에 설치된 공정설비(process module)에서 가스 누출에 의한 가스폭발 하중에 대한 해양구조물의 비선형 동적 거동응답 특성파악을 파악하기 위하여 LS-DYNA 코드의 유체-구조 연성(Fluid-Strycture Interaction) 해석기법을 적용하여 폭발 압력파를 보다 정확하게 구현하기 위한 기법을 개발하고자 한다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.7
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• pp.731-738
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• 2012

In this study, the evaluation of the aerodynamic characteristics of the NREL Phase VI Rotor System has been performed, for the 7 m/s upwind case using commercial FEA and CFD tools which are ANSYS Mechanical 12.1 and CFX 12.1. The initial operating conditions of the rotor blade include a $3^{\circ}$ tip pitch angle. A numerical simulation was carried out on only the rotor parts, excluding the tower structure based on the equivalent stiffness model, to consider the aeroelastic effect for the numerical simulation using the loosely coupled 2-way fluid-structure interaction method. The blade root bending moment was monitored in real time to obtain reasonable results. To verify the analysis results, the numerical simulation results were compared with the measurements in the form of the root bending moment and the pressure distributions of the NREL/NASA Ames wind tunnel test.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.8-13
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• 2018

A fluid-structure interaction analysis should be performed to evaluate the behavior of the internal fuel and its influence in order to confirm the structural soundness of the fuel tank against external impacts. In the past, fluid-structure interaction analyses have been limited to the obtention of numerical simulation results due to the need for considerable computational resources and excessive computation time. However, recently, computer performance has been dramatically improved, enabling complex numerical analyses such as fluid-structure interaction analysis to be conducted. Lagrangian and Euler coupling methods and Lagrangian based analysis methods are mainly used for fluid-structure interaction analysis. Since both of these methods have their advantages and disadvantages, it is necessary to select the more appropriate one when conducting a numerical analysis. In this study, a numerical analysis of a crash impact test for a fuel tank is performed using ALE. The purpose of the numerical analysis is to estimate the possibility of failure of the fuel tank mounted inside the container when it is subjected to a crash impact. As a result of the numerical analysis, the fluid behavior inside the fuel tank is investigated and the stress generated in the fuel tank and the container structure is calculated, thereby enabling the possibility of fuel tank failure and leakage of the internal fluid to be evaluated.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.4
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• pp.31-37
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• 2011

Fuel tank sloshing noise of vehicle is caused by flow impact on the tank wall during sudden braking, and the sloshing vibration of tank wall is a coupled phenomenon of the fuel inside tank and tank wall structure. Therefore, Fluid-Structure Interface(FSI) analysis technology should be adopted to predict accurately the sloshing vibration. In this study, FSI approach was employed to analyze sloshing phenomenon for a simple tank model with velocity change of the actual vehicle test. First, the simulated results for rigid tank model were compared with those for deformable tank model. Next, influence of baffle location and shape of baffle holes on the acceleration magnitude and the maximum stress of tank wall was investigated. In addition, sloshing analysis for tank with another baffle type was carried out.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.465-470
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• 2001

In this study, the seismic analysis of rack structure with fluid-structure interaction is performed through use of the Finite Element Method(FEM) code ANSYS. Fluid-structure interaction can specify in terms of an hydrodynamic effect which is defined as the added mass per unit length divided by the area of the cross section. Using the Floor Response Spectrum(FRS) obtained through the time-history analysis, modal analysis and seismic analysis under Operating Basis Earthquake(OBE) and Safe Shutdown Earthquake(SSE) condition is carried out. The fluid-structure interaction effects on the rack structure are investigated.

• Journal of the Society of Naval Architects of Korea
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• v.50 no.5
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• pp.343-348
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• 2013

When a natural frequency of the trailing edge of a wing is close to a vortex shedding frequency, an amplitude of the edge oscillation becomes maximal; it makes intensive noise called singing. Motion of the trailing edge may also feedback to the vortex shedding so that self-sustained oscillation appears, and a resonant frequency is locked in some interval of the speed of the incident flow. In this study, we first evaluate main features of oscillating characteristics of the wing. Second we simulate fluid-structure interaction of the wing with a flap using a commercial code, ANSYS-CFX, and investigate lift characteristics in a frequency domain.