• Journal of Power System Engineering
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• v.10 no.4
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• pp.43-49
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• 2006

Nowadays, the thermal environments of classrooms are usually adjusted by the ceiling type air-conditioning system with a temperature sensor installed on inlet of an air-conditioner. However, it is not clear that the conventional temperature sensor position is proper to satisfy both thermal comport and energy saving in summer especially. Therefore, this study is aimed at finding out the best position of the temperature sensor on the purpose of the comfort thermal environment and energy saving. The different 5 positions for the temperature sensor are supposed in this paper to analyze thermal environment by CFD. From the analysis through the CFD simulations, the best position of the temperature sensor satisfying for both comfort thermal environment and energy saving is obtained.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2009.05a
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• pp.268-268
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• 2009

고밀도 유도 결합 플라즈마를 이용한 연료 전기 분리판용 질화 장치를 플라즈마를 모사할 수 있는 3차원 전산 유체 역학 프로그램인 CFD-ACE+를 이용하여 해석하였따. 내장형 안테나 타입의 유도 결합 플라즈마의 전자 온도, 밀도 균일성, 가스 유동, 얇은 기판이 촘촘히 적재 되었을 경우의 플라즈마 특성을 모사하였다.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.86.1-86.1
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• 2011

To improve the safety, the fuel cell operate inside a pressurized enclosure which contains inert gas so called protective gas. The protective gas not only prevents the mixture of hydrogen and oxygen, but also removes the water in the vessel with the condenser. This study presents the details of the flow optimization in order to reduce the humidity in the fuel cell housing. The protective gas flow in the fuel cell container is studied by Computational Fluid Dynamics(CFD) simulations. This study focuses on optimizing the geometry of an protective gas circulation system in fuel cell module to reduce the humidity in the vessel. CFD analysis was carried out for an existing model to understand the flow behavior through the fuel cell system. Based on existing model CFD results, geometrical changes like inlet placement, optimization of outlet size, modification of fuel cell module system are carried out, to improve the flow characteristics. The CFD analysis of the optimized model is again carried out and the results show good improvement in protective gas flow behavior.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.2 no.1
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• pp.43-51
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• 2001

Metacomputing system is the environment, which helps the users easily and promptly deal with their jobs. with integration of the distributed computing resources and visualization device. In this research, we have developed a prototype of a special-purpose metacomputing system for simulation in CFD(Computational Fluid Dynamics) field. This system supports the automatic remote compilation, transparent data distribution, the selection of appropriate computing resource, and the realtime visualization. This research can be summarized as following: a study on selecting resource and the integration of component systems. In the research of selecting computing resource, we use the property of CFD algorithm. In the research of realtime visualization. we modify a popular visualizer.

• International Journal of Aeronautical and Space Sciences
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• v.7 no.2
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• pp.121-127
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• 2006

An analysis procedure for the combined problem of control algorithm and aeroelastic system which is based on the computational fluid dynamics(CFD) technique has been developed. The aerodynamic forces in the transonic region are calculated from the transonic small disturbance(TSD) theory. An linear quadratic regulator(LQR) controller is designed to suppress the transonic flutter. The optimal control gain is estimated by solving the discrete-time Riccati equation. The system identification technique rebuilds the CFD-based aeroelstic system in order to form an adequate system matrix which involved in the discrete-time Riccati equation. Finally the controller, that is constructed on the basis of system identification technique, is used to suppress the flutter phenomenon of the airfoil with attached store. This approach, that is, the CFD-based aeroservoelasticity design, can be utilized for the development of effective flutter controller design in the transonic region.

• 한국전산유체공학회:학술대회논문집
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• 2000.10a
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• pp.9-14
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• 2000

Computational methods can be classified roughly into two parts: one is the methods based on a potential flow theory, and the other is numerical solvers(CFD) based on Navier-Stockes equation. Methods based on a potential theory are more effective than CFD when the free surface effect is considered. Especially Rankine source method seems to become widespread for simulations of wave making problems. For computations of viscous flow problems, CFD techniques have rapidly been developed and have shown many successful results in the viscous flow calculation. Present paper introduces a computational system 'WAVIS' which includes a pre-processor, potential ant viscous flow solvers and a post-processor. To validate the system, the calculated results for modem commercial hull forms are compared with measurements. It is found that the results from the system are in good agreement with the experimental data, illustrating the accuracy of the numerical methods employed for WAVIS.

• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.524-529
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• 2010

In the present study, a CFD program is developed for the Fluid-Structure Interaction(FSI) analysis. The non-staggered, non-orthogonal, and unstructured grid system was also used to handle the complicated geometries in the program. In order to validate the capabilities of the developed CFD program, various models are investigated by using unstructured and nonorthogonal meshes. The predicted results are a good agreement with analytic solution, experimental data and commercial software. And also PISO algorithm is applied for transient flow analysis. The cyclic boundary condition and baffle cell are developed in order to improve the effectiveness of the calculation for complex geometry.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.1184-1189
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• 2008

This paper is a study about characteristics of the SSC-1 nozzle, which is used in a fire extinguishing system in a ship. Through this paper, we can find that the traces and elements’ distributions obtained from experiments are as the same as the simulation analysis results of CFD program. At the point of 100mm, the $\alpha$ is 34.9 in the CFD analysis, and it is 32.5 in the experiment. This shows that there is no big different between the CFD analysis and the experiment result. And the average elements velocity is similar to the SMD.

• Journal of Environmental Impact Assessment
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• v.21 no.1
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• pp.133-142
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• 2012

Convection Current Circulation System(CCCS) in stratified reservoir controls development of anaerobic condition and algal bloom during summer. In order to increase the CCCS effectiveness, we analyze diverse design parameters to make optimize the flow pattern in reservoir. In this study, we interpret the internal flow with installation and operation condition of CCCS based on CFD in reservoir. Design variables of CCCS is reservoir depth, stratification strength, distance of between CCCS and so on. Since reservoir depth and stratification strength in variables is depending on natural phenomenon, we evaluated current circulation effect by distance of CCCS and proposed the optimal design condition using CFD simulation. Flow and diffusion changes in water body was assessed by temperature and dye test. Changes in water floor temperature at 40m intervals was slowly descending over 37 hours. Dye diffusion simulation at 60m intervals, the radius of the spread between two devices were overlapped after 12 hours.

• 한국전산유체공학회:학술대회논문집
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• 1998.11a
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• pp.29-35
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• 1998

In this paper, the on-going effort and progress for developing an integrated software for automated CFD application is described. As an outcome of the effort devoted so far, a new system, ICFDIT, is developed and introduced in this paper. The new system can be used to solve fluid dynamics problems in a convenient graphical environment, and it includes a pre-processor, a main-processor, and a post-processor. Usage of the system and examples are demonstrated, and some issues for improvement of the system are discussed.