• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.517-523
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• 2010

Recently, the rapid evolution of computational fluid dynamics (CFD) has enabled its key role in industries and predictive sciences. From diverse research disciplines, however, are there strong needs for integrated analytical tools for multi-phenomena beyond simple flow simulation. Based on the concurrent simulation of multi-dynamics, multi-phenomena beyond simple flow simulation. Based on the concurrent simulation of multi-dynamics, multi-physics and multi-scale phenomena, the multi-phenomena CFD technology enables us to perform the flow simulation for integrated and complex systems. From the multi-phenomena CFD analysis, the high-precision analytical and predictive capacity can enhance the fast development of industrial technologies. It is also expected to further enhance the applicability of the simulation technique to medical and bio technology, new and renewable energy, nanotechnology, and scientific computing, among others.

• New & Renewable Energy
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• v.7 no.4
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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.

• Journal of Drive and Control
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• v.16 no.1
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• pp.36-44
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• 2019

Variable displacement swash plate piston pump analysis requires electric, hydraulics and dynamics which are similar to the one's incorporated in the complex fluid power and mechanical systems. The main variable capacity for the swash plate piston pumps, hydraulics or simple kinematic (swash plate degree, piston displacement) models are analyzed using AMESim, a multi-physics analysis program. AMESim is a multi-physics hydraulic analysis program that is considered good for the environment but not appropriate for environmental analysis for multibody dynamics. In this study, the analytical model of the swash plate type hydraulic piston pump variable capacity is modeled by combining the hydraulic part and the dynamic part through co-simulation of multibody dynamics program (Virtual.lab Motion) and multi-physics analysis (AMESim). This paper describes the whole modeling analysis method on the mechanical analysis of the multi-body dynamics program and how the hydraulic analysis in multi-physics analysis program works. This paper also presents a methodology for analyzing complex fluid power systems.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.6
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• pp.175-181
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• 2004

This paper presents the main method to analyze the dynamic characteristics of power transmission system using the multi-body dynamics, which is based on the concept of subsystem equation, subsystem assembling, and the self-determination technique for the system degree of freedom. We can model the mechanical components of power transmission system easily with the advantage of multi-body dynamics. Based on the theory, a dynamic simulation program was developed to analyze system performances, transient phenomena, and other dynamic problems. The driving performance of automatic transmission was simulated with using the multi-body dynamics and Newtonian method, and the validity of program was proved by comparing the two kinds of result.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.1
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• pp.70-81
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• 2017

Various components of an engine nozzle are modeled as flexible multi-body components that are operated under high temperature and pressure. In this paper, in order to predict complex behavior of an engine nozzle, thermo-fluid-flexible multi-body dynamics coupled analysis framework was developed. Temperature and pressure on the nozzle wall were obtained by the steady-state flow analysis for a two-dimensional nozzle. The pressure and temperature-dependent material properties were delivered to the flexible multi-body dynamics analysis. Then the deflection and strain distribution for a nozzle configuration was obtained. Heat conduction and thermal analyses were done using MSC.NASTRAN. The present framework was validated for a simple nozzle configuration by using a one-way coupled analysis. A two-way coupled analysis was also performed for the simple nozzle with an arbitrary joint clearance, and an asymmetric flow was observed. Finally, the total strain result for a realistic nozzle configuration was obtained using the one-way and two-way coupled analyses.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.5
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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.

• Journal of the Korea Institute of Military Science and Technology
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• v.4 no.1
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• pp.13-19
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• 2001

It is known that displacements, velocities and accelerations of the tractor- trailer type vehicle system in shock & vibration analysis by the flexible-multi-body dynamics including the flexibility of structure are bigger and more repetitive than them by the rigid-multi-body dynamics, and it is necessary to prove above results by the experimental field test. Therefore, in this paper, theoretical analysis by the flexible-multi-body dynamics and experimental field test for a tractor-trailer type vehicle system are conducted and their results are compared with each other. Because of unexpected metal contact and impact in the air coupler part in the field test, some accelerations measured from the experimental field test are bigger than them analyzed from the theoretical analysis, but most accelerations are well coincide with each other in the amplitudes and trends. Thus more refined dynamic analytical models for some special type vehicle systems will be possible in the future.

• Journal of the Chungcheong Mathematical Society
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• v.30 no.1
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• pp.141-149
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• 2017

In this article, we consider the Hyers-Ulam stability in multi-valued dynamics. We prove the Hyers-Ulam stability for a cubic set-valued functional equation on multi-valued dynamics by using several methods.

• Journal of the Chungcheong Mathematical Society
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• v.31 no.1
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• pp.89-101
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• 2018

In this paper, we consider the Hyers-Ulam stability on multi-valued dynamics. For a generalized n-dimensional quadratic set-valued functional equation, we prove the Hyers-Ulam stability for the functional equation in multi-valued dynamics.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.8
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• pp.1227-1234
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• 2001

A multi d.o.f robotic manipulator is considered for multi-axis vibration control of a slender structure, using the concept of the flow source based vibration control. In order not to cause the motion saturation of the manipulator system, a hybrid dynamics associated with the flexible and desired manipulator error dynamics is also modeled as the control object. It is numerically shown that the flexible vibrations and the base motions of a test structure can be effectively controlled with the proposed hybrid dynamics.