• 제어로봇시스템학회:학술대회논문집
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• 1997.10a
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• pp.488-491
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• 1997

The PMGS(Plant Model Generating System) was developed based on modular modeling method and fluid network calculation concept. Fluid network calculation is used as a method of real-time computation of fluid network, and the module which has a topology with node and branch is defined to take advantages of modular modeling. Also, the database which have a shared memory as an instance is designed to manage simulation data in real-time. The applicability of the PMGS was examined implementing the HRSG(Heat Recovery Steam Generator) control logic on DCS.

• Korea-Australia Rheology Journal
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• v.21 no.3
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• pp.161-173
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• 2009

This study analyzes especially drag and lift models recently developed for fluid-solid, fluid-fluid or liquid-liquid two-phase flows to understand their applicability on the computational fluid dynamics, CFD modeling of pulsatile blood flow. Virtual mass effect and the effect of red blood cells, RBCs aggregation on CFD modeling of blood flow are also shortly reviewed to recognize future tendencies in this field. Recent studies on two-phase flows are found as very useful to develop more powerful drag-lift models that reflect the effects of blood cell's shape, deformation, concentration, and aggregation.

• Journal of applied mathematics & informatics
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• v.42 no.2
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• pp.291-303
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• 2024

In this paper, we consider a feedforward network of overloaded multiclass processor sharing queues and we give a fluid model solution under the condition that the system is initially empty. The main theorem of the paper provides sufficient conditions for a fluid model solution to be linear with time. The results are illustrated through examples.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.19 no.7
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• pp.659-666
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• 2009

This paper proposes a new method for dynamic modeling of electrorheological(ER) damper considering fluid compressibility. After describing configuration and operating principle of the ER damper, a quasi-static modeling of the ER damper is conducted on the basis of Bingham model of ER fluid. Subsequently, the dynamic model for describing the ER damper considering compressibility of ER fluid and gas chamber is obtained using the lumped parameter method. This method includes dynamic motions of annular duct, upper chamber, lower chamber and connecting pipe. The hysteresis behavior of the ER damper is evaluated through computer simulations and compared with experimental results. In addition, the hysteresis behavior due to the compressibility of ER fluid and gas chamber is investigated through computer simulations.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.04a
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• pp.438-443
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• 2009

This paper proposes a new method for dynamic modeling of electrorheological (ER) damper considering fluid compressibility. After describing configuration and operating principle of the ER damper, a quasi-static modeling of the ER damper is conducted on the basis of Bingham model of ER fluid. Subsequently, the dynamic model for describing the ER damper considering compressibility of ER fluid and gas chamber is obtained using the lumped parameter method. This method includes dynamic motions of annular duct, upper chamber, lower chamber and connecting pipe. The hysteresis behavior of the ER damper is evaluated through computer simulations and compared with experimental results. In addition, the hysteresis behavior due to the compressibility of ER fluid and gas chamber is investigated through computer simulations.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.14-20
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• 2014

This study, the reliability of weapon systems acquisition and research and development in order to increase the effect of the modeling and simulation method has been studied using computational fluid dynamics. Weapon system acquisition, Test & Evaluation for use in the modeling and simulation can reduce the reliability of the time and cost savings and possible predictions and verification, and can provide useful data. However, the current weapon system acquisition and active use of modeling and simulation and verification do not even use the software are restricted. In this study, using computational fluid dynamics (CFD) modeling and simulation using the GAMBIT and FLUENT modeling and simulation was performed. The result is better than previous research results were confirmed in future weapon systems acquisition and research and development are expected to be actively used.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.6
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• pp.105-112
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• 2003

This paper presents the numerical design technology of a passive orifice fluid damper system especially for the characteristics between the damper piston velocity and the damping force. Numerical analysis with the visual interfacial modeling technique was applied into the analysis of the damper system's dynamics. A prototype orifice fluid damper was manufactured and experimentally tested to validate the numerical simulation results. The performances of various damper system schemes were investigated based on the verified numerical simulation model of orifice fluid damper.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2001.10a
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• pp.297-300
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• 2001

Physical modeling technique is applied to investigate foam generation in molten aluminum. By using room temperature water with specially designed equipment, the effects of stirrer type, fluid viscosity(glycerine added to water) and stirring velocity on foam generation behaviors are intensively analysed The distribution and size of bubbles varied with each process parameters but the most important parameters are stirring velocity and fluid viscosity. The results obtained from physical simulation have been confirmed by actual aluminum foam generation experiment at various process variables.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.265-266
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• 2007

• Computers and Concrete
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• v.19 no.3
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• pp.325-331
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• 2017

In this study, vibration and stability of concrete pipes reinforced with carbon nanotubes (CNTs) conveying fluid are presented. Due to the existence of CNTs, the structure is subjected to magnetic field. The radial fore induced with fluid is calculated using Navier-Stokes equations. Characteristics of the equivalent composite are determined using Mori-Tanaka model. The concrete pipe is simulated with classical cylindrical shell model. Employing energy method and Hamilton's principal, the motion equations are derived. Frequency and critical fluid velocity of structure are obtained analytically based on Navier method for simply supported boundary conditions at both ends of the pipe. The effects of fluid, volume percent of CNTs, magnetic field and geometrical parameters are shown on the frequency and critical fluid velocity of system. Results show that with increasing volume percent of CNTs, the frequency and critical fluid velocity of concrete pipe are increased.