• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.180.2-180.2
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• 2010

Simulation technology for dynamic analysis of wind turbine is developed. The Aerodyn and the DAFUL are chosen for aerodynamic analysis and multi-body and flexible body dynamics respectively. Subroutines and variables of Aerodyn developed by NREL are analyzed with hub-height wind data, full field turbulent wind data and Airfoil data. The interface to perform coupled analysis between AeroDyn and DAFUL, GUI for modeling several parts of wind turbines are developed. The program will be extended to analyze the coupled analysis of aerodynamic and hydrodynamic behavior for floating offshore wind turbines.

• 항공우주시스템공학회지
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• 제16권6호
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• pp.106-113
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• 2022

본 연구에서는 eVTOL 개인항공기의 개별 블레이드 피치 제어용 선형 구동기 기본설계 모델에 대한 구조 안전성을 검토하였다. Stall 하중에 대한 정적 구조 안전성을 검토하기 위해 유한요소법을 이용한 응력해석을 수행하여 안전여유율을 계산하였다. 또한 선형 구동기의 운용조건에 대한 피로수명을 평가하기 위해 피로 해석을 수행하였다. 다물체 동역학 분석을 통해 블레이드 피치각에 따른 하중이력을 산출하였다. 또한 정하중 해석에 정격하중을 적용하여 응력 분포를 산출하고 피로 해석에 활용하였다. 해석 결과, 선형 구동기의 모든 부품은 0 이상의 안전여유율이 계산되었고, 10⁷ cycles 이상의 피로수명이 산출되어 구조적으로 안전함이 확인되었다.

• 한국소음진동공학회논문집
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• 제17권11호
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• pp.1069-1076
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• 2007

The purpose of this study is to improve the performance of a linear feeder that can transport grains uniformly. In order to analyze the dynamic behaviors of a linear feeder, the displacements of the feeder are measured by several accelerometers when it is in an operating condition. After the signal data from the accelerometers are captured in the time domain, the feeder motion in the space is visualized by using graphic computer software. In addition, a dynamic model of the feeder is established for a multi-body dynamics simulation. For the dynamic simulation, RecurDyn, which is a commercial multi-body dynamic package, is used. From the experimental and the computational approaches, an optimal dynamic motion is obtained for uniform transportation of grains. Furthermore, we also consider the determination of design parameters for optimal dynamic motion such as centroid, stiffness, and damping coefficient of the feeder system.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2009년 추계학술대회논문집
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• pp.211-217
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• 2009

The numerical program has been developed for the purpose of the complicate geometries application using CIP method. The non-staggered, non-orthogonal, and unstructured grid system can be also used for the various geometries in the program. For validating CIP solver, the lid-driven cavity flow and solitary wave propagation flow are carried out. Test results show a good agreement with the verified results. The dynamic solver was used for the behavior of moving body. Interface process between the two solvers is introduced. The research was performed on the flow problem around torpedo and log and the flow problem in a tank in order to analyze the three phase flow problem Although the comparison to the verified results was not quantitatively performed, the trend of the results was reasonable.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.875-879
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• 2007

The effects of the statistical properties of the Coulomb friction coefficients on the dynamic responses of a galloping quadruped robot are investigated in this paper. In general, the Coulomb friction coefficients are assumed to be deterministic for a controller design to achieve required motion characteristics. However, the friction coefficients between the ground and the robot legs are not constant in reality. Therefore, statistical characteristics of the friction coefficients need to be considered for a multi-body modeling of the robot galloping on the ground. The effects of the statistical properties on the dynamic responses of the quadruped robots are investigated.

• 대한기계학회논문집A
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• 제28권9호
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• pp.1422-1428
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• 2004

In this paper, computer simulation model of handrail band including pulley-driving system is developed to calculate handrail slippage. This handrail simulation model is validated with test result within operating range and used to predict its slippage behavior with respect to variation of 4 different design parameters considering the applicability into the real handrail system. Based upon this parameter study, optimal condition for handrail slippage improvement is proposed without time-consuming and costly experiments of the real handrail system. And then performance improvement of handrail slippage complied with safety code is achieved after applying the optimal condition into the real handrail band system.

• 한국군사과학기술학회지
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• 제11권5호
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• pp.12-22
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• 2008

In this study, the dynamic characteristics for the wheel-type landing gear system of helicopter have been analyzed. Nonlinear multi-body dynamic models of the landing gear system are constructed and the equations of motion, kinematics and internal forces of shock strut are considered. In addition, flexibility effect of the wheel axle with equivalent beam element is taken into account. General purpose commercial finite code, SAMCEF which includes MECANO module is applied. The results of dynamic simulation for various landing and weight conditions are presented and compared with each other. Based on the results, characteristics of impact dynamic behaviors of the landing gear system are practically investigated.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.676-679
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• 2006

The media transport in automatic office machines such as printers, ATMs, copying machines is achieved by a complicated belt system. The system generally uses a crowning roller and belt which has been well-known for its intrinsic belt centering advantage during its operation. Since the modern office machines require precise high operating speed, stabilization of media transporting system has been one of the important issues of the machine design. Even a minor defect of the belt or the roller in the transport system directly affects its operating stability. This paper delivers a simulation technique that combines a multi-body dynamics analysis routine and a FEM based flexible continuum modeling for the efficient simulation of the flexible media transport problems.

• 한국위성정보통신학회논문지
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• 제3권1호
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• pp.29-34
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• 2008

발사체로부터 분리된 위성체가 궤도상에 진입하면 가장 먼저 태양전지판을 전개한다. 태양전지판의 전개유무는 위성 임무의 성공에 관련되어 있는 매우 중요한 요소 중 하나이다. 따라서, 설계 초기 단계에서부터 태양전지판 전개해석을 통하여 태양전지판의 거동을 예측하고, 전개 중 태양전지판 주요 부위에서의 하중을 계산하여, 태양전지판 전개안전성을 점검하는 것이 반드시 필요하다. 본 논문에서는 다몸체동역학 해석프로그램을 이용하여 차세대 저궤도 위성의 태양전지판 전개해석을 수행하고, 그 결과로부터 태양전지판 전개시 안정성을 분석하였다. 또한, 전개해석시 필요한 힌지 특성 데이터는 힌지 특성 시험을 수행하여 구하였으며, 이의 결과를 전개해석에 반영하여 해석을 수행하였다.

• 한국자동차공학회논문집
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• 제22권2호
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• pp.175-181
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• 2014

A four-link mechanism consisting of torsion bars is used for opening the trunk lid in most midsize sedans. When the weight of the lid is in equilibrium with the spring force exerted by torsion bars, the lid stops opening at a pop-up height. However, the actual pop-up height has large deviations from the specified height even with the same parts in the same car model, which leads to quality issues. Automotive manufacturers have experienced this deviation problem despite much effort to resolve it. In this research, we developed a multi-body dynamics model for the analysis of pop-up deviation of a trunk lid with torsion bars, which can simulate the actual pop-up motion of the trunk lid by considering kinematic constraints of the motion and friction forces in joints. We could also determine the most important factor that governs the pop-up height by sensitivity analysis of all parts. The developed system can be used for the analysis of other trunk lid systems to control the tolerance of parts.