• 상하수도학회지
• /
• 제27권4호
• /
• pp.495-502
• /
• 2013

Hydraulic dead-zone and particle removal efficiency in the base frame of a constructed wetland was evaluated with computational fluid dynamics (CFD). The fraction of hydraulic dead-zone was estimated to be 1.2-2.1 % (v/v) and it was attributed to the artificial islands developed in the constructed wetland. Solids deposition rate could be increased with higher hydraulic retention time (HRT, ranged from 2.2 to 4.2 hr) of the wetland and larger particle size (ranged from 10 to $50{\mu}m$) in the influent. Experimental results showed that the volume concentration of the particles smaller than $10{\mu}m$ in diameter was varied from $1.99{\times}10^3{\mu}m^3/ml$ (HRT 12.8 hr) to $3.92{\times}10^3{\mu}m^3/ml$(HRT 2.2 hr) in the influent of the constructed wetland. With the effluent volume concentration data, removal efficiency of those particles was calculated to be 71.2 and 24.7 % when the HRT was 12.8 and 2.2 hr, respectively. Similar trend with the HRT variation could be identified with CFD analysis.

• 한국수소및신에너지학회논문집
• /
• 제17권4호
• /
• pp.403-408
• /
• 2006

The plate reformer consisting of combustion chamber and reforming chamber for 25 kW MCFC stack has been operated and computational fluid dynamics was applied to estimate reactions and thermal fluid behavior in the reformer. The methane air 2-stage reaction was assumed in the combustion chamber, and three step steam reforming reactions were included in the calculation. Flow uniformity, reaction rate and species distribution, and temperature distribution were analyzed. In particular, temperature distribution was compared with the measurements to show good agreement in the combustion chamber, however, inappropriate agreement in the reformer chamber.

• 한국전산유체공학회:학술대회논문집
• /
• 한국전산유체공학회 2011년 춘계학술대회논문집
• /
• pp.453-457
• /
• 2011

In this study, transonic aeroelastic response analyses haw been conducted for the business jet aircraft configuration considering shockwave and flow separation effects. The developed fluid-structure coupled analysis system is applied for aeroelastic computations combining computational structural dynamics(CSD), finite element method(FEM) and computational fluid dynamics(CFD) in the time domain. It can give very accurate and useful engineering data on the structural dynamic design of advanced flight vehicles. For the nonlinear unsteady aerodynamics in high transonic flow region, Navier-Stokes equations using the structured grid system have been applied to wing-body configurations. In transonic flight region, the characteristics of static and dynamic aeroelastic responses have been investigated for a typical wing-body configuration model. Also, it is typically shown that the current computation approach can yield realistic and practical results for aircraft design and test engineers.

• 한국전산유체공학회:학술대회논문집
• /
• 한국전산유체공학회 2008년도 춘계학술대회논문집
• /
• pp.236-239
• /
• 2008

In the present study, a transient glass particle distribution in a stirred solid/liquid mixer was investigated using computational fluid dynamics(CFD). The flow patterns and solid concentaration distriburion in a solid/liquid mixer formed by pitched paddle and baffles were predicted. The numerical results were compared to experimental data from the available literature. Eulerian multi-phase model was used to investigate the influence of the density of solid particle on the same impeller speed. A good agreement was obtained between the experimental data and simulation results.

• 한국산학기술학회논문지
• /
• 제2권1호
• /
• pp.43-51
• /
• 2001

메타컴퓨팅 시스템은 분산된 컴퓨팅 자원들과 가시화 장비들을 통합하여 사용자가 편리하고 신속하게 작업을 처리할 수 있게 해 주는 환경이다. 본 연구에서는 전산유체역학(CFD : Computational Fluid Dynamics) 프로그램 개발자들을 위한 메타컴퓨팅 시스템을 개발하였다. 본 시스템에서 사용자는 프로그램을 컴퓨팅 자원에 분산시키고 분산환경에서 컴파일 할 수 있으며 프로그램구조에 적합한 컴퓨팅 자원에서 그 결과를 동영상을 통하여 얻을 수 있다. 본 연구에서는 다음과 같이 두 가지 연구를 수행하였다. 전산유체역학 프로그램의 구조를 이용한 자원선정에 대한 연구, 요소시스템 통합연구. 컴퓨팅 자원 선정을 위해 전산유체역학 프로그램의 구조적인 특징을 이용하였고 실시간 가시화를 위하여 기존의 가시화 도구를 수정하여 통합하였다.

• 한국항공운항학회:학술대회논문집
• /
• 한국항공운항학회 2005년도 추계학술발표대회 논문집
• /
• pp.176-181
• /
• 2005

• 한국가시화정보학회지
• /
• 제6권1호
• /
• pp.19-26
• /
• 2008

• 한국가시화정보학회지
• /
• 제2권2호
• /
• pp.8-15
• /
• 2004

With all the recent progresses in computer hardware and software technology, the animation of fluids in real-time is still among the most challenging issues of computer graphics. The fluid animation is carried out in two steps - the physical simulation of fluids immediately followed by the visual rendering. The physical simulation is usually accomplished by numerical methods utilizing the particle dynamics equations as well as the fluid mechanics based on the Navier-Stokes equations. Particle dynamics method is usually fast in calculation, but the resulting fluid motion is conditionally unrealistic. The methods using Navier-Stokes equation, on the contrary, yield lifelike fluid motion when properly conditioned, yet the complexity of calculation restrains this method from being used in real-time applications. This article presents a rapid fluid animation method by using the continuum-based fluid mechanics and the enhanced particle dynamics equations. For real-time rendering, pre-integrated volume rendering technique was employed. The proposed method can create realistic fluid effects that can interact with the viewer in action, to be used in computer games, performances, installation arts, virtual reality and many similar multimedia applications.

• 한국전산유체공학회:학술대회논문집
• /
• 한국전산유체공학회 2011년 춘계학술대회논문집
• /
• pp.179-182
• /
• 2011

The purpose of this study is to evaluate a defrost model for the possibility of defrosting on wheelhouse window and the heat capacity if defrosting nozzle by using the commercial CFD solver FLUENT. A detailed simulation model has been created which contains the defrosting nozzle, window and the interior/exterior forced convection boundary. In this numerical study, the heat and mass transfer coupled during defrosting and investigated the defrost time for different hot gas temperature, external wind speed and temperature condition.

• 한국전산유체공학회:학술대회논문집
• /
• 한국전산유체공학회 2011년 춘계학술대회논문집
• /
• pp.199-201
• /
• 2011

NACA0012 Airfoil was simulated with Computational Fluid Dynamics(CFD) and the aerodynamic characteristics was analyzed for various far-field boundary distances ranging from 10 airfoil chord to 50 chord Drag coefficient distribution was dependent on the far-field distance and circulation, integrated along the loop inside the flow region, was also dependent. It was turned out that some corrections based on the circulation should be added to the far-field boundary condition for accurate airfoil simulation.