• 소성∙가공
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• 제21권6호
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• pp.366-371
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• 2012

Atomistic simulations have become useful tools for exploring new insights in materials science, but the length and time scale that can be handled with atomistic simulations are seriously limiting their practical applications. In order to make meaningful quantitative predictions, atomistic simulations are necessarily combined with higher-scale modeling. The present research is thus concerned with the development of a multi-scale model and its application to the prediction of the mechanical properties of body-centered cubic(BCC) iron with an emphasis on the coupling of atomistic molecular dynamics with meso-scale discrete dislocation dynamics modeling. In order to achieve predictive multi-scale simulations, it is necessary to properly incorporate atomistic details into the meso-scale approach. This challenge is handled with the proposed hierarchical information passing strategy from atomistic to meso-scale by obtaining material properties and dislocation mobility. Finally, this fundamental and physics-based meso-scale approach is employed for quantitative predictions of the mechanical response of single crystal iron.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.906-909
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• 2005

This study provides the method to build the rotor system model using dynamic analysis software. also, it introduces the traditional methods of the rotor system modeling and informs the each merits and demerits. We will make up the flexible system of rotor system model with ADAMS, multi-body dynamics S/W, in order to develop dynamics model and get the response of plant model near to real model through connection the SIMULINK of MATLAB. We will develop the computing dynamics-controling model possible controlled simulation similar to a real model with controlling the plant model.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 창립기념 춘계학술대회 논문집
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• pp.517-524
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• 1998

A liner numerical model of the wheel-rail interation and the track geometry is developed for multi-body dynamics program. The simulation results are very simulation to these of VAMPIRE simulation. This program can be used for the analysis of train dynamic performance.

• 한국기계가공학회지
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• 제15권3호
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• pp.115-121
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• 2016

A mackerel grader is a machine for sorting mackerel according to size. In this study, the dynamic deflection and optimal sorting simulation of a mackerel grader was carried out by using multi-body dynamics. To analyze the dynamic deflection of the roller, RecurDyn, a multi-body dynamics analysis program, was used. The dynamic deflection of the roller pipe was analyzed according to the inclination of the roller pipe. When the inclination of the roller pipe was 30 degrees, the roller indicated the maximum deflection of about 6.3 mm at the center of the mass. To simulate the mackerel sorting, the mackerel grader machine was modeled, and the contact simulation between the mackerel model and the rotating roller pipe was carried out. When the inclination of the roller frame was 7 degrees, the mackerel grader indicated optimal sorting performance.

• 한국소음진동공학회논문집
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• 제24권5호
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• pp.363-373
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• 2014

In this study, computational multi-body dynamic analyses for the drivetrain system of a 5 MW class offshore wind turbine have been conducted using efficient equivalent modeling technique based on the design guideline of GL 2010. The present drivetrain system is originally modeled and its related system data is adopted from the NREL 5 MW wind turbine model. Efficient computational method for the drivetrain system dynamics is proposed based on an international guideline for the certification of wind turbine. Structural dynamic behaviors of drivetrain system with blade, hub, shaft, gearbox, supports, brake disk, coupling, and electric generator have been analyzed and the results for natural frequency and equivalent torsional stiffness of the drivetrain system are presented in detail. It is finally shown that the present multi-body dynamic analysis method gives good agreement with the previous results of the 5 MW class wind turbine system.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.1093-1098
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• 2002

Dynamic behaviors of the Korean High-speed Train(KHST) have been analyzed to investigate the performance on the stability, the safety and the ride comfort. Multi-body dynamics analysis program using Recursive method, called RecurDyn, have been employed in the numerical simulation. To model the wheel-rail contact, the RecurDyn uses its built-in module which uses the square root creep law. The accuracy of the rail module in RecurDyn. however, decreases in the analysis of flange contact because it linearizes the shape of the wheel and rail. To solve this problem, a nonlinear contact theory have been developed that considers the profiles of the wheel and rail. The results show that the KHST still needs more stability. The problem should be solved by the examinations of module and modeling.

• 드라이브 ㆍ 컨트롤
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• 제21권2호
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• pp.44-52
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• 2024

In this study, we predicted PTO power requirements based on torque predicted by the discrete element method and the multi-body dynamics coupling method. Six different scenarios were simulated to predict PTO power requirements in different soil conditions. The first scenario was a tillage operation on cohesionless soil, and the field was modeled using the Hertz-Mindlin contact model. In the second through sixth scenarios, tillage operations were performed on viscous soils, and the field was represented by the Hertz-Mindlin + JKR model for cohesion. To check the influence of surface energy, a parameter to reproduce cohesion, on the power requirement, a simple regression analysis was performed. The significance and appropriateness of the regression model were checked and found to be acceptable. The study findings are expected to be used in design optimization studies of agricultural machinery by predicting power requirements using the discrete element method and the multi-body dynamics coupling method and analyzing the effect of soil cohesion on the power requirement.

• 한국기계기술학회지
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• 제20권6호
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• pp.836-843
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• 2018

In this paper, dynamic model of 120mm self-propelled mortar is developed, and multi flexible body dynamics analysis is performed to analyze stresses occurring in the mount during mortar fire. For this, vehicle dynamic system, mortar dynamic system, and finite element mount model are proposed. The commercial program Recurdyn is used in the analysis. As a result of the analysis, the maximum stress(146.9MPa) occurred at the mount side plate. In order to analyze the validity of the analysis results, we performed strain measurement tests by selecting three major points, and the errors of results were 7.91%, 11.15%, and 18.23%, respectively. It is confirmed that the tendency of analysis and test is similar.

• 한국산업융합학회 논문집
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• 제20권5호
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• pp.431-439
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• 2017

Since the power transmission line(PTL) passes through the high mountain and heavy snowfall region, it is necessary to keep the stability of the PTL. In this study, PTL is modeled as a mass-spring-damper system by using RecurDyn. The lumped mass model is verified by calculated from the simulation comparing the deflection analysis according to the sag and tension. In order to analyze the dynamic behavior of PTL, a damping coefficient for a multi-body model is derived by using the free vibration test and Rayleigh damping theory. Sleet jump simulation according to the region is performed. The maximum jump height, icing sag and amount of jump are confirmed. Also, the amount of jump and the reaction force at the supporting point according to the tension and load of ice are analyzed, respectively. As a result, it is noted that the amount of jump and reaction force are influenced more by the load of ice than by the tension of PTL.

• 한국자동차공학회논문집
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• 제16권2호
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• pp.58-65
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• 2008

The finite element programs have been developed for structure, collision, flow, dynamics, heat transfer, acoustics, electromagnetism, MEMS (Micro Electro Mechanical Systems), and etc. These programs can be classified as either "package" program or "single purpose" program. Single purpose programs usually have convenient and powerful functions, but these programs have limited expandability to different fields of analysis. Therefore, the method to converter the analysis results of single purpose program to other programs is needed. In the research, multi-body data conversion methods of 1) finite element model and 2) solid model were created to convert fluid analysis result of CFD-ACE+ to ANSYS data structure. Automatic boundary condition algorithms were developed for blade, and finite element model was compared with solid model. It is expected that, by sealess data transfer, the Multi-body Data Conversion Program could reduce the development period of torque converters.