• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 추계학술대회 논문요약집
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• pp.239-239
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• 2003

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1714-1717
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• 2003

ECCOMAS Thematic Conference Multibody 2003 was held at IST (Instituto Superior Technico), Lisbon, Portugal from July 1 to July 4. 2003. And MBDV(Multibody Dynamics and Vibration) in the 2003 ASME DETC was held at Chicago, U.S.A. from September 2 to September 6. In this paper, the presented papers in these conferences were reviewed and the trends in the multibody dynamics are summarized. The session titles in these conferences include Flexible Multibody Dynamics, Vehicle Dynamics, Contact, Biomechanics, Real-time Challenges, Spatial manipulator and Control, Multidisciplinary Applications, and Advanced Education. The poster session was also organized for more discussions in the Multibody2003 conference.

• 한국정밀공학회지
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• 제21권5호
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• pp.114-121
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• 2004

Recently, the finite element absolute nodal coordinate formulation (ANCF) was developed for the large deformation analysis of flexible bodies in multi-body dynamics. This formulation is based on the finite element procedures and the general continuum mechanics theory to represent the elastic forces. In this paper, a computation method of dynamic stress in flexible multi-body dynamics using absolute nodal coordinate formulation is proposed. Numerical examples, based on an Euler-Bernoulli beam theory, are shown to verify the efficiency of the proposed method. This method can be applied for predicting the fatigue life of a mechanical system. Moreover, this study demonstrates that structural and multi-body dynamic models can be unified in one numerical system.

• 신재생에너지
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• 제7권4호
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• pp.50-57
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• 2011

A wind turbine simulation program for the coupled dynamics of aerodynamics, elasticity, multi-body dynamics and controls of turbine is newly developed by combining an aero-elastic code and a multi-body dynamics code. The aero-elastic code, based on the blade momentum theory and generalized dynamic wake theory, is developed by NREL(National Renewable Energy Laboratory, USA). The multi-body dynamics code is commercial one which is capable of accounting for geometric nonlinearity and twist deflection. A turbulent wind load case is simulated for the NREL 5-MW baseline wind turbine model by the developed program and FAST. As a result, the two results agree well enough to verify the reliability of the developed program.

• 대한기계학회논문집A
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• 제38권2호
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• pp.115-120
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• 2014

본 연구에서는 다물체 동역학 해석 소프트웨어인 RecurDyn 을 이용하여 풍력 발전기를 쉽게 모델링하고 동적 거동 해석을 수행할 수 있는 기법을 개발하였다. 풍력 발전기는 타워, 너셀, 허브, 그리고 블레이드로 구성되어 있다. 타워와 블레이드는 탄성체로 가정하였고 탄성효과를 고려하기 위하여 탄성체 이론을 이용하여 모델링 하였다. 바람의 속도는 일정하다고 가정하였고 날개 요소 운동량 이론을 이용하여 공력하중을 모델링 하였다. 이를 통해 계산된 공력을 풍력 발전기에 적용시키고 동적 거동 해석을 수행하였다. 해석의 타당성을 검증하기 위하여 풍력 발전 시스템 상용 소프트웨어인 GH-Bladed를 이용한 해석결과와 비교하였다.

• 대한기계학회논문집A
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• 제29권8호
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• pp.1123-1131
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• 2005

In this paper, a formulation for a spatial sliding joint, which a general multibody can move along a very flexible cable, is derived using absolute nodal coordinates and non-generalized coordinate. The large deformable motion of a spatial cable is presented using absolute nodal coordinate formulation, which is based on the finite element procedures and the general continuum mechanics theory to represent the elastic forces. And the non-generalized coordinate, which is neither related to the inertia forces nor external forces, is used to describe an arbitrary position along the centerline of a very flexible cable. In the constraint equation for the sliding joint, since three constraint equations are imposed and one non-generalized coordinate is introduced, one constraint equation is systematically eliminated. Therefore, there are two independent Lagrange multipliers in the final system equations of motion associated with the sliding joint. The development of this sliding joint is important to analyze many mechanical systems such as pulley systems and pantograph/catenary systems for high speed-trains.

• 한국자동차공학회논문집
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• 제5권1호
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• pp.101-109
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• 1997

A tool for the dynamic simulation and design technique of the excavator plays an important role in the prediction of dynamic behavior of the excavator in the initial design stage. In this paper, a flexible multibody dynamic analysis model including track of the crawler type excavator is developed using DADS and ANSYS. Through the driving simulation of the excavator travelling over rough road track, frequency characteristics of the upper frame and cabin are obtained, and the reaction forces acting on the track rollers are also presented for the fatigue life estimation. The effect of boom vibration modes on the joint reaction forces and accelerations is presented from the swing simulation.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1730-1735
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• 2003

In this paper, the absolute nodal coordinate formulation was introduced to describe the large deformation problems. And also, the modal coordinates were employed to represent the small elastic deformation. A new hybrid formulation was developed to combine the modal coordinates and the absolute nodal coordinates. A spherical joint and the DOT1 constraint were developed to carry out the numerical simulation of mechanical systems with kinematic joints. A beam example was suggested to show the new formulation. The simulation results using the modal coordinates and the absolute nodal coordinates show a good agreement to the experiments.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 춘계학술대회 논문집
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• pp.78-83
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• 2009

In this study, computer applied engineering (CAE) techniques are fully used to conduct structural and dynamic analyses of a whole huge wind turbine system including composite blades, tower and nacelle. For this study, computational fluid dynamics (CFD) is used to predict aerodynamic loads of the rotating wind-turbine blade model. Multi-body dynamic structural analyses are conducted based on the non-linear finite element method (FEM) by using super-element method for composite laminates blade. Three-dimensional finite element model of a wind turbine system is constructed including power train(main shaft, gear box, coupling, generator), bedplate and tower. The results for multi-body dynamic simulations on the wind turbine's critical operating conditions are presented in detail.

• 한국자동차공학회논문집
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• 제17권4호
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• pp.63-71
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• 2009

The elastic effects of the valve train components are analyzed by using the finite element models of the rocker arm and valve. The whole equations of motion of the valvetrain of an internal combustion engine formulated by finite element techniques are solved by imposing the contact conditions with the augmented Lagrange multiplier method. The velocity and acceleration constraints as well as the displacement constraints are imposed on the contact points. The numerical simulations show that, even if the magnitude of the elastic deformation of the components is very small, it may have large effects on the valvetrain dynamics of a high-speed engine.