• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2011년 춘계학술대회논문집
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• pp.25-30
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• 2011

In this study, it is performed numerical simulation on multi-phase flow by means of CIP-CSI2 scheme. It is applied In a two-phase free surface flow problem at a high density ratio equivalent to that of an air-water system, for examining the computational capability. The method that is being developed and improved is a CIP(Constrained Interpolation Profile) and CSL2(Conservative Semi-Lagrangian) based Cartesian Grid Method.

• 한국해양공학회지
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• 제27권2호
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• pp.39-46
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• 2013

In this study, the impact loads on tank walls by sloshing phenomena and on a tall structure in a three-dimensional rectangular tank were predicted using multiphase flow simulations. The solver was based on the CIP/CCUP (Constraint interpolation CIP/CIP combined unified procedure) method, and the THINC-WLIC (Tangent hyperbola for interface capturing-weighted line interface calculation) scheme was used to capture the air-water interface. For the convection terms of the Navier-Stokes equations, the USCIP (Unsplit semi-lagrangian CIP) method was adopted. The results of simulations were compared with those of experiments. Overall, the comparisons were reasonably good.

• 한국전산유체공학회지
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• 제10권2호
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• pp.7-14
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• 2005

In this study, the shallow water equations on the sphere is simulated by the proposed method which has high spatial resolution and is based on the CIP(Cubic Interpolated Pseudoparticle) method. The governing equations are approximated on the longitude-latitudinal coordinate system. To avoid the problems resulting from the convergence of the meridians toward high-latitude and singularities on the poles, the semi-Lagrangian and finite volume method are employed. in addition, the CIP method is employed to solve the advection equations and is extended to apply on the equations in the polar coordinate system. The mathematical formulation and numerical results are also described. To verify of the efficiency, accuracy and capability of proposed algorithm, the standard test cases proposed bv Williamson et. al are simulated and the results are compared with other results. As a result, it is found that the present scheme gives a good properties in preserving shapes of solution and settles the pole problems in solving the shallow water equations on the sphere.

• International Journal of Ocean System Engineering
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• 제1권3호
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• pp.136-143
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• 2011

In this paper, three-dimensional free-surface flows are simulated by using two different numerical methods, the constrained interpolation profile (CIP)-based and finite volume (FV)-based methods. In the CIP-based method, the governing equations are solved on stationary staggered Cartesian grids by a finite difference method, and an immersed boundary technique is applied to deal with wave-body interactions. In the FV-based method, the governing equations are solved by applying collocated finite volume discretization, and body-fitted meshes are used. A free-surface boundary is considered as the interface of the multi-phase flow with air and water, and a volumeof-fluid (VOF) approach is applied to trace the free surface. Among many variations of the VOF-type method, the tangent of hyperbola for interface capturing (THINC) and the compressive interface capturing scheme for arbitrary meshes (CICSAM) techniques are used in the CIP-based method and FV-based method, respectively. Numerical simulations have been carried out for dam-breaking and wave-body interaction problems. The computational results of the two methods are compared with experimental data and their differences are observed.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2009년 추계학술대회논문집
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• pp.211-217
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• 2009

The numerical program has been developed for the purpose of the complicate geometries application using CIP method. The non-staggered, non-orthogonal, and unstructured grid system can be also used for the various geometries in the program. For validating CIP solver, the lid-driven cavity flow and solitary wave propagation flow are carried out. Test results show a good agreement with the verified results. The dynamic solver was used for the behavior of moving body. Interface process between the two solvers is introduced. The research was performed on the flow problem around torpedo and log and the flow problem in a tank in order to analyze the three phase flow problem Although the comparison to the verified results was not quantitatively performed, the trend of the results was reasonable.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1821-1826
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• 2003

In this study, we discuss CIP method, which can treat compressible/incompressible problem and multi-phase problem. We can apply this method to the general equations by using CCUP. In this paper, non-staggered grid arrangement and predictor-corrector method are used to enhance later development and the solution accuracy and convergence performance. To validate the numerical algorithm proposed in this paper, the two-dimensional unsteady flow in the driven cavity is simulated. The numerical results of this subject using the present algorithm are compared with other numerical results. As a result, it is prived that the present scheme gives stable and improved solutions, and the results even coarse grid are in good agreement with other result using a fine grid arrangement.

• Journal of Mechanical Science and Technology
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• 제19권12호
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• pp.2263-2269
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• 2005

The ship wave phenomena in the restricted waterway were investigated by a numerical analysis. The Euler and continuity equations were employed for the present study. The boundary fitted and moving grid system was adopted to enhance the computational efficiency. The convective terms in the governing equations and the kinematic free surface boundary condition were solved by the Constrained Interpolated Profile (CIP) algorithm in order to solve accurately wave heights in far field as well as near field. The advantage of the CIP method was verified by the comparison of the computed results by the CIP and the Maker and Cell (MAC) method. The free surface flow simulation around Wigley hull was performed and compared with the experiment for the sake of the validation of the numerical method. The present numerical scheme was applied to the free surface simulation for various canal sections in order to understand the effect of the sectional shape of waterways on the ship waves. The wave heights on the side wall and the shape of the wave patterns with their characteristics of flow are discussed.

• 한국전산유체공학회지
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• 제16권2호
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• pp.1-10
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• 2011

A new computational program, which is based on the CIP/CCUP(Constraint Interpolation Profile/CIP Combined Unified Procedure) method, has been developed to numerically analyse sloshing phenomena dealt as multiphase-flow problems. For the convection terms of Navier-Stokes equations, the RCIP(Rational function CIP) method was adopted and the THINC-WLIC(Tangent of Hyperbola for Interface Capturing-Weighted Line Interface Calculation) method was used to capture the air/water interface. To validate the present numerical method, two-dimensional dam-breaking and sloshing problems in a rectangular tank were solved by the developed method in a stationary Cartesian grid system. In the case of sloshing problems, simulations by using a improved MPS(Moving Particle Simulation) method, which is named as PNU-MPS(Pusan National University-MPS), were also carried out. The computational results are compared with those of experiments and most of the comparisons are reasonably good.

• 한국전산유체공학회지
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• 제9권3호
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• pp.8-17
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• 2004

A Semi-Lagrangian method based on CIP(Cubic Interpolated Pseudoparticle)method is proposed and it is applied to solve the two dimensional advection equation. Especially the attentions are given to settle the pole problem and to enhance the accuracy in solving the advection equation on the spherical coordinate system. Tn this algorithm, the CU method is employed as the Semi-Lagrangian method and extended to the spherical coordinate system. To enhance the accuracy of the solution, the spatial discretization is made by CIP method. The mathematical formulation and numerical results are also described. To verify the efficiency, accuracy and capability of proposed algorithm, two dimensional rotating cosine bell problem and the frontogenesis problem are simulated by the present scheme. As results, it is confirmed that the present scheme gives an accurate solution and settles the pole problem in the advection equation on the sphere.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.53-56
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• 2008

A reinforced concrete (RC) cast-in-place (CIP) infill wall retrofitting method may provide an improved seismic performance and economical efficiency for the non-ductile rahmen structures. In this study, four one story-one bay non-ductile frame were constructed and retrofitted with CIP infill wall to evaluate seismic performance of CIP infill wall-frame. From the test results, infill wall-frame exhibited a marked increase in shear strength compared to non-ductile RC frame specimen. But the ductility and story-drift at maximum load were decreased when shear strength of infill wall larger than that of existing RC frame. Therefore, it is confirmed that adequate reinforcement detail is required to assure sufficient seismic performance.