• Journal of Biosystems Engineering
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• v.41 no.3
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• pp.184-192
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• 2016

Purpose: To solve the decay phenomenon of Hanfu apples that occurs during storage and obtain the best environmental parameters for preserving Hanfu apples using Fluent. Methods: Preservation storage was designed by analyzing the characteristics of Hanfu-apple storage and the natural environment in northeast China. The boundary conditions and simulation of a preservation model were established. Results: Compared with the initial values, the hardness decreased by $1.95kg/cm^2$, the sugar-acid ratio decreased by 20.43, and weight-loss rate was 3.98%. Conclusion: The results for the temperature field and velocity field of the empty storage were analyzed using Fluent. Hanfu apples can maintain good quality during the period of storage, according to our analysis of the Hanfu-apple hardness, weight loss, and change in the sugar-acid ratio during the 90-day preservation period.

• 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.

• Wind and Structures
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• v.20 no.1
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• pp.59-74
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• 2015

A coupled model system for Wind Resource Assessment (WRA) was studied. Using a mesoscale meteorological model, the Weather Research and Forecasting (WRF) model, global-scale data were downscaled to the inner nested grid scale (typically a few kilometers), and then through the coupling Computational Fluid Dynamics (CFD) mode, FLUENT. High-resolution results (50 m in the horizontal direction; 10 m in the vertical direction below 150 m) of the wind speed distribution data and ultimately refined wind farm information, were obtained. The refined WRF/FLUENT system was then applied to assess the wind resource over complex terrain in the northern Poyang Lake region. The results showed that the approach is viable for the assessment of wind energy.

• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.6
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• pp.70-77
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• 2011

A ventilation-relief valve performs as a safety-valve assembly for the liquid-propellant feeding system of space launch vehicle. This valve plays a role of relieving the vaporized propellants from propellant tanks during the filling and storing stages of propellants. Also it regulates to maintain the pressure of ullage volume of on-board propellant tanks within the safety-margin during the flight. The simulation model of ventilation-relief valve is designed with AMESim to predict and evaluate the dynamic characteristics and pneumatic behaviors of valve. To validate a valve simulation model, the simulation results of the opening and closing pressures and their operating durations of valve by AMESim analysis are compared with the results of mathematical methods. In addition, the results of internal flow simulation with FLUENT are utilized to improve the accuracy of valve-modeling. This study will serve as one of reference guides to enhance the developmental efficiency of ventilation-relief valves with the various operating conditionss, which shall be used in Korea Space Launch Vehicle-II.

• Journal of the Korean Electrochemical Society
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• v.6 no.1
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• pp.28-35
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• 2003

A numerical analysis of electrochemical reaction and dynamics of the fluid flow in the channels of a DMFC separator was carried out by using a commercial Computational Fluid Dynamics(CFD) code fluent(ver.6.0). From the simulation work, many valuable informations were obtained in terms of distributions of velocity, pressure, temperature, concentration and current density over the flow field. And it was possible to optimize the flow field structure by using the simulation results. The simulation work using the Cm code was found very helpful in analysing the phenomena occurring in the fuel cell and optimizing the structures of electrodes and flow field.

• International Journal of Fluid Machinery and Systems
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• v.8 no.3
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• pp.124-131
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• 2015

The good performance of a vortex shedder is defined by strong and stable vortex generated under the condition of most linearity in Strouhal number and low power loss. In this paper, the flow past a bluff body of circular cylinder with a slit normal to the flow has been analyzed focusing on drag coefficient, linearity of Strouhal number and flow resistance (K-factor). The ANSYS/FLUENT package is used for flow simulation and the integration method of computational code to iSIGHT platform is employed for automated design cycle. This study results the design with (0.20~0.267) blockage ratio and 0.10 slit ratio as the best shedder for vortex flowmeter and this results are in well agreement with the experiment. As the combination of GAMBIT, FLUENT, and iSIGHT substitutes the design parameters automatically according to the input data, this method designs effectively the vortex shedder with less design cycle time and low manufacturing cost eliminating the human intervention bottleneck.

• Journal of ILASS-Korea
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• v.22 no.4
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• pp.159-168
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• 2017

Numerical studies on the spray characteristics of closed-type and open-type swirl injectors were conducted using ANSYS Fluent. By changing injection pressures, discharge coefficient and spray angle were calculated using the Reynolds stress BSL turbulent model. The numerical results were compared with previous experimental data to examine their accuracy. For a closed-type swirl injector, spray angles matched well with experimental results and discharge coefficients showed approximately 8% differences. On the contrary, discharge coefficients of an open-type swirl injector were similar with experimental result but its spray angles presented around 15% differences. Though the numerical results were not perfectly consistent with experimental data, it is thought that they could be sufficiently used for analyzing spray characteristics, specially which is hard to be measured from experiments. Numerical simulation with different turbulent models was also performed to examine their effects on the numerical results.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.699-703
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• 2017

Numerical simulations of closed-type and open-type single injectors were conducted to investigate the flow characteristics of a swirl-coaxial injector used in a liquid rocket engine. Numerical analysis was conducted using a commercial program ANSYS FLUENT. The injectors has three models with different recess length. Numerical analysis was conducted to investigate the variation of the flow characteristics of the injector when the flow condition were changed. It was also compare and analyzed with experimental results. The results obtained from the numerical simulation show that the difference between the inlet pressure and the discharge coefficient is not significant.

• Proceedings of KOSOMES biannual meeting
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• 2018.06a
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• pp.145-145
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• 2018

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.562-562
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• 2014

Assessment of aerodynamic noise is becoming increasingly important for automotive manufacturers. Flow passing a vehicle may indeed lead to high interior noise level and affect cabin comfort. Interior noise results from various mechanisms including aerodynamic fluctuations of the disturbed flow around the side mirror or pillar, hydrodynamic and acoustic loading of the car panels and windows, vibration of these panels and acoustic radiation inside the vehicle. Objective of the present study is to capture these important mechanisms in a simulation model and demonstrate the ability of the combined simulation tools Fluent / Virtual.Lab to provide accurate aerodynamic and interior noise prediction results. Previous study focused on the noise generated by the turbulence around the A-pillar structure of the HSM (Hyundai simplified model). The present study also includes the effect of the side-mirror and rain-gutter structures. Complete modeling process is presented including details on the unsteady CFD simulation and the vibro-acoustic model with absorption materials. Guidelines and best practices for building the simulation model are also discussed.