• Biomedical Science Letters
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• v.10 no.3
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• pp.245-251
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• 2004

Microbial infection provokes one of the most serious complications to the patients with indwelling catheters. Ciprofloxacin (CFX) was added into the catheter materials (polyurethane or silicone) during the manufacturing process to avoid the microbial infection. Efficacy of the catheters containing CFX was investigated by using the in vitro zone of growth inhibition test method. The catheters made of polyurethane or silicone exhibited a strong antimicrobial activity against the major catheter-related microorganisms (S. aureus, S. epidermidis, P. aeruginosa and E. coli), when CFX was incorporated into the catheters. Fetal bovine serum (FBS) did not affected antimicrobial activities of the polyurethane catheters with CFX loading of 0.5 and 1.0％ (W/W) against S. aureus and S. epidermidis. However, the polyurethane catheters with 1.0％ (W/W) of CFX loading showed a significantly (P<0.05) reduced antimicrobial activity against E. coli when the catheters were exposed to FBS. Silicone catheters with 1.0 and 1.5％ (W/W) of CFX loading demonstrated effective antimicrobial activity against S. epidermidis for at least 2 weeks. These results suggest that the use of catheters containing ciprofloxacin could be effective in preventing catheter-related infections.

• The KSFM Journal of Fluid Machinery
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• v.15 no.5
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• pp.37-41
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• 2012

High-efficiency and low-noise axial flow fan is developed by combining the FanDAS, a computerized axial fan design/performance analysis system, and CFD software(CFX). Based on fan design requirements, FanDAS conducts 3-D blade geometry design, quasi-3D flow/ performance analyses and noise evaluation by using through-flow analysis method and noise models for discrete frequency and broadband noise sources. Through the parametric studies of fan design variables using FandDAS, preliminary and baseline design is achieved for high efficiency and low noise fan, and then can be coupled with a CFD technique such as the CFX code for constructing final and optimized fan design. The FanDAS-CFX coupled system and its design procedure are applied to actual fan development practice. The FanDAS provides an optimized 3-D fan blade geometry, and its predictions on the performance and the noise level of designed fan are well agreed with actual test results.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.582-586
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• 2012

본 연구에서는 ANSYS CFX 모형을 이용하여 임의형상 파샬플륨 내에서의 유동모의 및 해석을 수행하였다. 상류경계조건으로 파샬플륨 상류 2m 지점을 기점으로 하여 상류수위를 0.2, 0.25 그리고 0.3m로 변화시켰으며, 하류경계조건은 상류수위의 0.5, 0.8 그리고 0.9로 변화시키면서 모의를 수행하였다. 모의된 결과는 수리모형실험으로부터 측정된 결과와 FLOW-3D 모형에 의한 모의결과와의 비교를 통해 검증하였다. 또한, 격자 시스템의 조밀도 정도(T-1, T-2, T-3, T-4)에 따른 유동변화 양상을 분석하였다.

• Journal of Power System Engineering
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• v.18 no.3
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• pp.5-13
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• 2014

In order to control emissions from engine, it is necessary to understand the mixture formation process of diesel spray. In this study, analysis of diesel fuel(n-Tridecane, $C_{13}H_{28}$) spray under a high temperature and pressure was performed by a general-purpose program, ANSYS CFX release 11.0, and the results of these are compared with experimental results of diesel fuel spray using the Exciplex Fluorescence Method. The simulation results of diesel spray is analyzed by using the combination of Large-Eddy Simulation(LES) and Lagrangian Particle Tracking(LPT), and then injection pressure was selected as an analysis parameter. Consequently, it was found that the experimental results and the numerical results are consistent with each other, and then in order to investigate the behavior characteristics of evaporative diesel spray, the effectiveness of the use of CFX of commercial code is definitely validated.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.11a
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• pp.174-175
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• 2005

The purpose of this study is focused on the analysis of 3D complex flow and performance characteristics of a centrifugal pump with volute casing. The numerical analysis was performed by commercial code CFX-10 according to the variation of flow rate, which is changing from 5.847$m^3$/min to 6.865$m^3$/min. The rated rotational speed of close type impeller is 1750rpm. Turbulence model, k-${\omega}$ SST was selected to guaranty more accurate prediction of flow separation. The ICEM-CFD 10, reliable grid generation software was also adapted to secure high quality grid generation necessary for the reliable numerical simulation. The experimental results such as static head, brake horse power and efficiency of the centrifugal pump were compared with the numerical analysis results. The simulated results are good agreement with the experimental results less 5$%$ error.

• The KSFM Journal of Fluid Machinery
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• v.7 no.5 s.26
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• pp.82-90
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• 2004

• 유체기계공업학회:학술대회논문집
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• 2004.12a
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• pp.396-401
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• 2004

In this paper, a 1MW HAWT(FIL-1000) rotor blade has been designed by BEMT(Blade Element Momentum Theory) with Prandtl's tip loss. Also, a 3-D flow and performance analysis on the FIL-1000 rotor blade has been carried out by using the 3-D Navier-Stokes commercial solver (CFX-5.7) to provide more efficient design techniques to the large-scale HAWT engineers. The rated power and itsapproaching wind velocity at design point (TSR=7.5) are 1MW and 9.99m/s respectively. The rotor diameter is 54.5m and the rotating speed is 26.28rpm. Airfoils such as FFA W-301, DU91-W-250, DU93-W-210, NACA 63418, NACA 63415 consist of the rotor blade from hub to tip. Recent CFX version, 5.7 was adopted to simulate 3-D flow field and to analyze the performance characteristics of the rotor blade. Entire mesh node number is about 730,000 and it is generated by ICEM-CFD to achieve better mesh quality The predicted maximum power occurringat the design tip speed ratio is 931.45kW. Approaching to the root, the inflow angle becomes large, which causesthe blade to be stalled in the region. Therefore, k-$\omega$ SST turbulence model was used to predict the quantitative flow information more accurately. Application of commercial CFD code to optimum blade design and performance analysis was proved to be more effective environment to HAWT blade designers.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1476-1481
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• 2004

In this paper, we present the flow and heat transfer characteristics with the array of impinging jet nozzles by using the numerical computation and experiment. Numerical solutions were obtained for dimensionless gap H=6, dimensionless outlet length L=10 and Reynolds number Re=1500 by using the commercial CFD code, CFX -5. Experimental and numerical results were agreed well with each other. It was found that the impinging jet with circular array nozzles generated the uniform heat transfer area and the maximum heat transfer is higher than rectangular array nozzles for certain parameter sets.

• Wind and Structures
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• v.5 no.2_3_4
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• pp.359-368
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• 2002

This paper describes a CFD investigation into the flow over the cab of a bluff-fronted lorry. Several different simulations were undertaken, using the commercial codes: CFX, Fluent and PowerFLOW. Using the $k-{\varepsilon}$ turbulence model, the flow over the cab was symmetric, however, using more accurate turbulence models such as the RNG $k-{\varepsilon}$ model or the Reynolds Stress Model, the flow was asymmetric. The paper discusses whether this phenomenon is a real effect or whether it is a solver artefact and the study is supported by experimental evidence. The findings are preliminary, but suggest that it has a physical origin and that it may be aspect ratio-dependent.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.157-160
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• 2008

Tip clearance is a critical point in turbine to reduce friction between blade and casing. To estimate the direct effectiveness of the tip clearance, numerically analyzed are flow passing through rotors with and without tip clearance. The Results by CFX tells that rotors with tip clearance have vortex structure which makes larger loss in turbine, and shows lower total-to-total efficiency than that without tip clearance.