• 한국전산유체공학회:학술대회논문집
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• 2002.10a
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• pp.8-16
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• 2002

Now, the era of information, the rapid acquisition of vast and various information acts as a key role. for the national competitiveness. The smart UAV is brought to the fore as a new future technology which will be able to satisfy the information needs in broad and stereoscopic manner. The smart UAV, with VTOL capability, higher performance, and reliability over the existing technology thresholds, will lead the aerospace technology in the future. In this paper, the technology concept of smart UAV, the necessity of development, and the trend of worldwide R&D are introduced and analyzed. In addition, for the Smart UAV Development Program which is launched by the 21c Frontier R&D program this year, the role and application area of the CFD will be discussed.

• Journal of Advanced Marine Engineering and Technology
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• v.35 no.7
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• pp.946-956
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• 2011

The main objectives of this study are to analyze the leaked gas dispersion and quantify the potential overpressures due to vapor cloud explosions in order to identify the most significant contributors to risk by using Computational Fluid Dynamics (CFX & FLACS) for gas fuelled ships. A series of CFD simulations and analyses have been performed for the various gas release scenarios in a closed module, covering different release rates and ventilating methods. This study is specially focused on the LNG FGS (Fuel Gas Supply) system recently developed for the propulsion of VLCC crude oil carriers by shipyards. Most of work presented is discussed on the gas dispersion from leaks in the FGS room, and shows some blast prediction validation examples.

• 한국전산유체공학회:학술대회논문집
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• 2001.05a
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• pp.161-169
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• 2001

At the end of 1999, the TeraCluster Project in the KISTI Supercomputing Center was initiated to explore the possibility of PC clusters as a scientific computing platform to replace the Cray T3E system in KISTI by 2002. Since actual performance of a computing system varies significantly for different architectures, representative in-house codes from major application fields were executed to evaluate the actual performance of systems with different combination of CPU, network and network topology. As an example of practical CFD(Computational Fluid Dynamics) simulations, the flow past the Onera-M6 wing and the flow past a infinite wing were simulated on a clusters of Linux and several other hardware environments.

• 한국전산유체공학회:학술대회논문집
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• 2004.10a
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• pp.121-125
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• 2004

The preprocessor - solver - postprocessor software for 2D/Axisymmetric CSCM Upwind Flux Difference Splitting Navier-Stokes code has been developed for undergraduate educational purpose. This computational fluid dynamics (CFD) software allows students to setup, solve, visualize and control dynamically server for their own fluid problems via Internet. The preprocessor Is capable of generating geometry and grid, initial solution data and required solver control parameters. The postprocessor shows vector plot and contour plot with different options while residual plot shows root-mean-square (RMS) error history graphically and retrieves the data from solver interactively. Special feature of the preprocessor is grid generation part which is based on MFC/Visual C++ application and FORTRAN single block grid generator process. Many users can access solver via Internet from client computers and solve desired problems using locally installed pre- and postprocessor and remote powerful solver part.

• Journal of computational fluids engineering
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• v.20 no.1
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• pp.26-31
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• 2015

A grid generation program for specific problems is introduced. The program allows users to easily generate grid system for specific geometry such as an airfoil, cylinder, wedge, flat plate, and nozzle. Generating grid system for those problems can be proceeded with minimum user inputs such as geometry-defining parameters and grid-defining parameters. By using this program learning stage for preprocessing of CFD application can be efficiently shorten and novice students can learn and acquire experience by trying out grid generation and CFD solution by themselves.

• Nuclear Engineering and Technology
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• v.44 no.1
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• pp.33-42
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• 2012

In the present study, CFD is employed to investigate phenomena occurring during a process of thermal stratification in U-bent pipes at transitional Reynolds number. URANS evaluation had been chosen for its low computational costs during transient analysis and for the evaluation of modeling performance in these conditions. Application of CFD at transitional Reynolds number and buoyancy driven flows indeed contains deeper uncertainties in relation to the range of applicability for hydrodynamic and thermal models. The methodology applied in the work points out, through validations with the basic problems constituting the complex stratified phenomenon, the applicability of the current turbulence modeling. Accurate predictions have been found in relation to transitional Reynolds number in bent pipes and region of stability induced by the gravitational field. On the other hand the defects introduced in the unstable region of the U bent pipe, are discussed in relation to the adopted modeling.

• 한국전산유체공학회:학술대회논문집
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• 2011.05a
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• pp.483-487
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• 2011

In the present study, a CFD program based on a finite volume method was developed by using an unstructured polyhedral grid system for the accurate simulation with the complex geometry of computational domain. To simulate the transient flow induced by the moving solid object, the program used a fractional step method and a ALE (Algebric Lagrangian-Eulerian) method. The grid deformation for the moving of solid object were performed with a spring analogy based on the center coordinate of each computational grid. To verify the present program with these methodologies, the numerical results of the flow around the fixed and oscillating circular cylinder were compared with the previous numerical results.

• Particle and aerosol research
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• v.19 no.3
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• pp.77-87
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• 2023

We present the development of a wetcyclone sampler designed for the sampling of airborne bacteria. The wetcyclone design involves a combination of two traditional cyclone shapes and computational fluid dynamics (CFD) analysis to validate its effectiveness in terms of pressure drop and collection efficiency. The wetcyclone exhibits a collection efficiency of over 90% for bacteria, specifically targeting Staphylococcus aureus. Additionally, the wetcyclone enables continuous bioaerosol sampling using a liquid medium (deionized water), demonstrating a concentration ratio exceeding >105 and a stable microbial recovery rate of 81.9%. The application of real-time quantitative polymerase chain reaction (qPCR) and the colony counting method ensures precise measurement of the concentration ratio and microbial recovery rate.

• Journal of Wetlands Research
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• v.19 no.4
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• pp.451-458
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• 2017

In this study, the removal efficiency of the wetland in terms of particulate matter and dead water zone through the application of baffles in the sedimentation were simulated with the use of Computational Fluid Dynamics (CFD) to determine the design of a cost-effective constructed wetland. As a result, it was analyzed that the application of the baffle in the sedimentation tank affect the flow and sedimentation rate. Fine particles such as $2{\mu}m$ and $5{\mu}m$ showed high sedimentation rate when the baffles are installed horizontally. large particles such as $10{\mu}m$ and $20{\mu}m$ showed also high deposition rate when the baffles are installed vertically. In addition, the vertical baffles is considered to be more efficient than other baffle types in terms of maintenance since the particulate matter are concentrated in narrow areas. Therefore, it is considered that the selection of the most applicable type of baffle depends on the design purpose of the wetland to be constructed.

• Journal of computational fluids engineering
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• v.18 no.3
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• pp.67-71
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• 2013

Recently, the rapid development of the semiconductor industry induces the prompt technical progress in the area of device integration and the application of large diameter wafers for the price competitiveness. As a result of the usage of large wafers in the semiconductor industry, the silicon carbide components which have layers of silicon carbide on graphite or RBSC substrates is getting widely used due to the advantages of SiC such as high hardness and strength, chemical and ionic resistant to all the environments superior than other ceramic materials. For the uniform and homogeneous deposition of silicon carbide on these huge components, it needs to know about the gas flow in the CVD reactor, not only for the delicate adjustment of the process variables but more essentially for the cost reduction for the shape change of specimens and their holders on the stage of reactor. In this research, the CFD simulation is challenged for the prediction of the inner distribution of the gas velocity. Chemical reaction simulation is used to predict the distribution of concentration of the reacting gas with the rotating velocity of the stage. With the increase of the rotating speed, more uniform distribution of the reacting gas on the surface of the stage was obtained.