• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2005년도 춘계 학술대회논문집
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• pp.153-158
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• 2005

Numerical simulations of two-dimensional steady incompressible lid-driven flow in a square cavity are presented to verify the validity of a new solution code(PowerCFD) with unstructured grids. The code uses the non-staggered(collocated) grid approach which is very popular for incompressible flow analysis because of its numerical efficiency on the curvilinear or unstructured grids. Solutions are obtained for configurations with a Reynolds number as high as 10,000 with both rectangular and hybrid types of unstructured grid mesh. Interesting features of the flow are presented in detail and comparisons are made with benchmark solutions found in the literature. It is found that the code is capable of producing accurately the nature of the lid-driven cavity flow at high Reynolds numbers.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제8권2호
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• pp.51-73
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• 2004

A boundary layer analysis is used to study the effects of Hall and ion-slip currents on the steady magneto-micropolar of a viscous incompressible and electrically conducting fluid over a horizontal plate. By means of similarity solutions, deviation of fundamental equations on the assumption of small magnetic Reynolds number are solved numerically by using the shooting method. The effects of various parameters of the problem, e.g. the magnetic parameter, Hall parameter, ion-slip parameter, buoyancy parameter and material parameter are discussed and shown graphically.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제22권3호
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• pp.155-162
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• 2018

We describe a parallel implementation of a relaxed Hermitian and skew-Hermitian splitting preconditioner for the numerical solution of saddle point problems arising from the steady incompressible Navier-Stokes equations. The equations are linearized by the Picard iteration and discretized with the finite element and finite difference schemes on two-dimensional and three-dimensional domains. We report strong scalability results for up to 32 cores.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제18권3호
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• pp.245-256
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• 2014

This work is focused on the boundary layer and heat transfer characteristics of hydromagnetic flow over a stretching sheet with variable thickness. Steady, two dimensional, nonlinear, laminar flow of an incompressible, viscous and electrically conducting fluid over a stretching sheet with variable thickness and power law velocity in the presence of variable magnetic field and variable temperature is considered. Governing equations of the problem are converted into ordinary differential equations utilizing similarity transformations. The resulting non-linear differential equations are solved numerically by utilizing Nachtsheim-Swigert shooting iterative scheme for satisfaction of asymptotic boundary conditions along with fourth order Runge-Kutta integration method. Numerical computations are carried out for various values of the physical parameters and the effects over the velocity and temperature are analyzed. Numerical values of dimensionless skin friction coefficient and non-dimensional rate of heat transfer are also obtained.

• 한국자동차공학회논문집
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• 제6권5호
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• pp.55-65
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• 1998

A numerical and experimental study of three-dimensional steady incompressible non-reacting flow inside various dual-monolith catalytic converters has been conducted for achievement of performance improvement, reduction of light-off time and longer service life by improving the flow uniformity within the monolith. In this study, the effects of curvature of inlet exhaust pipe and monolith brick length on the flow uniformity and pressure drop within monolith were numerically investigated. The computations are confirmed by measurements of steady flow. The agreement between computations and experiment was relatively good. The result of this study shows that curvature of inlet exhaust pipe and monolith brick length gave a great effect on the flow uniformity and the shorter the brick length, the lower flow uniformity and the less pressure drop.

• 충청수학회지
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• 제19권4호
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• pp.335-347
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• 2006

The homogenization of non-stationary Navier-Stokes equations on anisotropic heterogeneous media is investigated. The effective coefficients of the homogenized equations are found. It is pointed out that the resulting homogenized limit systems are of the same form of non-stationary Navier-Stokes equations with suitable coefficients. Also, steady Stokes equations as cell problems are identified. A compactness theorem is proved in order to deal with time dependent homogenization problems.

• 대한수학회지
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• 제40권6호
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• pp.1051-1060
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• 2003

We study the surface waves of an incompressible fluid passing over a small bump. A forced KdV equation for surface wave is derived without assuming that flow is uniform at far upstream. New types of steady solutions are discovered numerically. Two new cut off values of Froude number are found, above the larger of which two symmetric solutions exist and under the smaller of which two different symmetric solutions exist.

• 대한수학회지
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• 제36권1호
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• pp.159-171
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• 1999

We formulate and study a finite element method for a linearized steady state, compressible, viscous Navier-Stokes equations in 2D, based on the discontinuous Galerkin method. Dislike the standard discontinuous galerkin method, we do not assume that the triangle sides be bounded away from the characteristic direction. the unique stability follows from the inf-sup condition established on the finite dimensional spaces for the (incompressible) Stokes problem. An error analysis having a jump discontinuity for pressure is shown.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.651-654
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• 2002

Study of electric vehicle is popular with automobile company. However, battery cooling problem has delayed development of electric vehicle. Lifetime of electric vehicle's battery depends on the cooling effect for the battery tray. One model was simulated by 3-D, steady state, incompressible, k-e turbulent model simulation. It is found that flow inlet, outlet and inlet position are very important design parameters.

• EDISON SW 활용 경진대회 논문집
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• 제6회(2016년)
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• pp.1-3
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• 2016

대형 화물 트럭(heavy-duty truck)은 화물 적재에 용이하지만, 공기역학적으로 불리한 형상을 가진다. 이러한 단점을 극복하고자 대형 화물 트럭에는 공기저항력(aerodynamic drag)을 줄일 수 있는 여러 가지 장치가 달려있다. 본 논문에서는 디플렉터(deflector) 형상이 항력 감소에 어떠한 영향을 주며, 평판 형태와 굴곡진 형태의 디플렉터 형상에 대한 항력 계수 비교를 EDISON-CFD를 활용하여 비교하였다. 해석 결과, 측풍(side-wind)의 영향을 무시하며 차량 속도 95 km/h로 등속을 유지하는 조건에서 평판 형태의 Model 1과 바깥으로 굴곡진 Model 2에서 전체 항력 계수가 낮게 나타났다.