• 한국전산유체공학회:학술대회논문집
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• 2008.03a
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• pp.171-175
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• 2008

In the present study, a numerical simulations are investigated in a stirred solid/liquid system by using Eulerian multi-phase model. The transient flow field of liquid phase and distribution of solid particles are predicted in stirred tanks consisting of 4-pitched paddles impeller and baffles. The effects of number and width of baffles on the mixing time and the quality of solid suspension in a stirred tank are presented numerically. The result shows that the mixing time decreases as the width and number of baffles increase.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.597-602
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• 2006

Many researches have been studied several vibration control device such as TMD and TLD to reduce the influence of wind or seismic waves for high-rise buildings. TLD provides some advantages such as easy installation and low maintenance cost. However, because of the difficulties in evaluating the characteristics of TLD, the dynamic characteristics of TLD must be investigated by experiment or analysis. In this study, the dynamic response analysis of structure with TLD was carried out to verify the vibration control ability of the proposed TLD for high-rise building with about 60 stories. A real seismic wave was used, and the parameter of interest was chosen by the height of water level in the same shape of water tank. From the numerical results, the responses of structure with water tank were confirmed to be safer than those of structure without water tank.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.1406-1411
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• 2009

Stirred tanks are widely used in various industries for mixing operations and chemical reactions for single- or multi-phase fluid systems. In this study, a numerical study was conducted to predict the mixing characteristics in a simple stirred tank. The flow in the model stirred tank was calculated utilizing the multiple reference frame (MRF) and the sliding mesh (SM) capabilities of a commercial CFD code (Fluent 6.2). The results of the flow simulation were analyzed in terms of the mixing efficiency, and the applicability of MRF and SM methods was also discussed.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1997.04a
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• pp.115-127
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• 1997

A study to evaluate the seismic response of $\frac{1}{2}$-scaled liquid storage tank constructed in Hualien, is performed. And this study is to identify the liquid-structure-soil interaction by observed earthquake data ans analyzed results. After the calculation of soil impedance for the test site by SASSI code, 3-dimensional seismic response analysis is performed by BEM-FEM-Impedance Method with the consideration of liquid-structure-soil interaction when the tank is excited by real earthquake. The observed acceleration and hydrodynamic pressure are compared with the numerical results. This comparisons show good agreement in predominant frequency and maximum hydrodynamic pressure. And the free surface sloshing motion due to earthquake loadings is computed in time domain.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.2
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• pp.662-670
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• 2019

Tanker cargo tanks are equipped with the means of raising and maintaining the cargo discharge temperature to a suitable level. In this paper, a new heating coil design is proposed and analyzed. Contrary to conventional designs, wherein the heating coils are evenly distributed over the tank bottom, the proposed design arranges the heating coils in the central part of the tank bottom, in a vertical direction. Due to the intensive cargo circulation generated, a forced convection is superimposed on a buoyancy-driven natural convection, providing a more efficient mixed convection heat transfer mechanism. Numerical simulations performed by using a finite volume method show that in the case of 7-bar steam Bunker C heavy fuel oil heating, a five-hour circulation phase average heat transfer coefficient equals 199.2 W/m²K. This result might be taken as an impetus for the more thorough experimental examination.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.04a
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• pp.275-283
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• 1999

To predict the dynamic behavior of the cylindrical liquid storage tank subjected to seismic ground motion three dimesional analysis with liquid-structure interaction must be performed, In this study a three dimensional dynamic analysis method over the frequency domain using FE-BE coupling technique which combines the efficiency of the boundary elements for liquid with the versatility of the finite shell elements for tank. The liquid region is modeled using boundary elements which can counter the sloshing effect at free surface and the structure region the tank itself is modeled using the degenerated finite shell elements. At the beginning of the procedure the equivalent mass matrix of the liquid is generated by boundary elements procedure. Then this equivalent mass matrix is combined with the mass matrix of the structure to produce the global mass matrix in the equation of the motion of fluid-structure interaction problem In order to demonstrate the accuracy and validity of the developed method the numerical results re compared with the previous studies. Finally the effects of the fluid-structure interaction on the natural frequency and dynamic response of the system are analyzed.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.602-607
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• 2000

Fuel-storage tank is a representative example of liquid-structure interaction systems. In order to prevent the undesired structural failure by a variety of external loads, the reliable analysis of the dynamic response of such structural system is of a great importance. In this paper, we address the analytical study on free vibration of axisymmetric cylindrical fuel-storage tanks together with the parametric investigation of eigen-characteristics with respect to the relative fuel fill-height and the relative tank height. Numerical results illustrating theoretical results are also included.

• Journal of Advanced Research in Ocean Engineering
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• v.4 no.4
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• pp.163-173
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• 2018

There are many issues in fluid structure interactions when dealing with the free surface flows in a sloshing tank. For example the problem of how yielding a highly nonlinear wave with a simple forced motion over a short duration is of concern here. Nonlinear waves are generated in a rectangular tank which is forced horizontally; its motion consists of a single cycle of oscillation. One of the objectives is to end up with a shape of the free surface yielding a wide range of critical flows by tuning few parameters. The configuration that is studied here concerns a plunging breaker accompanied with a critical jet where great kinematics are simulated. The numerical simulations are performed with a twodimensional code which solves the fully nonlinear free surface boundary conditions in Potential Theory.

• Journal of Ocean Engineering and Technology
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• v.32 no.6
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• pp.440-446
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• 2018

The effects of an anti-rolling tank (ART) on vessel motions were numerically investigated. The potential-based BEM vessel motion simulation program and particle-based computational fluid dynamics program were dynamically coupled and used to perform a simulation of vessel motions with ART. From the time domain simulation results, the response amplitude operators for sway and roll motions were obtained and compared with the corresponding experimental and numerical results. Because the main purpose of ART was only to reduce roll motions, it was important to show that the natural properties of a floating vessel were not changed by the effects of ART. Various ART filling ratios and several ART positions were considered. In conclusion, ART only reduced the roll motion regardless of its filling ratio and position.

• Fire Science and Engineering
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• v.31 no.3
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• pp.49-53
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• 2017

In the present study, the hydrodynamic force acting on the vertical wall of a portable water storage tank is examined. A Dispersion Relation Preserving (DRP) method, proposed by Jang, is applied for simulating lapping waves and their impact on the wall. A meaningful investigation has been observed, which may be applied to the strength design for the portable water storage tank.