• 동력기계공학회지
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• 제9권4호
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• pp.65-70
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• 2005

A liquid storage rectangular tank structures are used in many fields of civil, mechanical and marine engineering. Especially, Ship structures have many tanks in contact with inner or outer fluid, like ballast, fuel and cargo tanks. Fatigue damages are sometimes observed in these tanks which seem to be caused by resonance with exciting force of engine and propeller. Vibration characteristics of these thin walled tanks in contact with fluid near engine propeller are strongly affected by added mass of containing fluid. Therefore it is essentially important to estimate the added mass effect to predict vibration of the tank structures. Many authors have studied vibration of cylindrical and rectangular tanks structures containing fluid. Few research on dynamic interaction among tank walls through fluid are reported in the vibration of rectangular tanks recently. In case of rectangular tanks, structural coupling between adjacent panels and effect of vibration modes of multiple panels on added mass have to be considered. In the present paper, coupling effect between panels of tank structure on added mass of containing fluid, the effect of structural constraint between panels on each vibration mode for fluid region have investigated numerically and experimentally.

• 동력기계공학회지
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• 제14권6호
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• pp.67-74
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• 2010

Many tanks are installed in ship and marine structures. They are often in contact with inner or outer fluid, like ballast, fuel and cargo tanks. Fatigue damages are sometimes observed in these tanks which seem to be caused by resonance with exciting force of engine and propeller. Vibration characteristics of these thin walled tanks in contact with fluid near engine and propeller are strongly affected by added mass of containing fluid. Therefore it is essentially important to estimate the added mass effect to predict vibration of the tanks. Many authors have studied vibration of cylindrical and rectangular tanks containing fluid. Few research on dynamic interaction among tank walls through fluid are reported in the vibration of rectangular tanks recently. In case of rectangular tanks, structural coupling between adjacent panels and effect of vibration modes of multiple panels on added mass have to be considered. In the previous report, A numerical tool of vibration analysis of a 3-dimensional tank is developed by using finite element method for plates and boundary element method for fluid region. In this paper, the coupling effect between panels of a tank on added mass of containing fluid, the effect of structural constraint between panels on each vibration mode for fluid region and mode characteristics in accordance with changing breadth of the plates are investigated numerically and discussed.

• 동력기계공학회지
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• 제15권1호
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• pp.24-31
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• 2011

Rectangular box type structures are used in many fields of civil, mechanical and marine engineering. Especially, Most ship structures are often in contact with inner or outer fluid, like ballast, fuel and stem tanks. Fatigue damages are sometimes observed in these tanks which seem to be caused by resonance with exciting force of engine and propeller. Vibration characteristics of these thin walled tanks in contact with fluid near engine and propeller are strongly affected by added mass of containing fluid. Therefore it is essentially important to estimate the added mass effect to predict vibration of the tanks. Many authors have studied vibration of rectangular tanks containing fluid. Few research on dynamic interaction among tank walls filled with fluid are reported in the vibration of rectangular tanks recently. In case of rectangular tanks, structural coupling between adjacent panels and effect of vibration modes of multiple panels on added mass of water have to be considered. In the previous report, a numerical analysis is performed for the coupling effect between panels of a tank on added mass of containing fluid, the effect of structural constraint between panels on each vibration mode for fluid region, and mode characteristics in accordance with changing breadth of the plates by using finite element method for plates and boundary element method for fluid region. In this paper, the coupling effect between panels of a tank on added mass of containing fluid, the effect of structural constraint between panels on each vibration mode for fluid region, and mode characteristics in accordance with changing length, thickness, and boundary condition of the plates are investigated numerically and discussed.

• Coupled systems mechanics
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• 제6권2호
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• pp.189-206
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• 2017

Tanks are used to store a wide variety of liquids such as oil, gasoline and water. It is reported that, a large number of tanks have been damaged during severe earthquakes. Therefore, understanding their behavior under earthquake is an important subject for structural engineers. In this paper, a comprehensive study is presented on dynamic response of tanks. A parametric study has been completed on the rectangular storage tanks with aid of finite element method (FEM). Various parameters are investigated, such as; liquid height, density and earthquake with different peak ground acceleration (PGA). When investigating these parameters, modal and time history method is used. Six different earthquake records are used for time history analysis. The analysis results show that when the PGA increases by 10.7 times, the maximum displacements, stress, sloshing and base shear increase by 11.4, 22.6, 5.46 and 17.8 times, respectively and when the liquid height increases by two times, the absolute maximum values of stress, displacements, base shear and sloshing increase 1.65, 2.04, 2.05 and 1.34. Furthermore, values of sloshing increase with decrease in density.

• 한국지진공학회논문집
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• 제27권6호
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• pp.303-310
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• 2023

The equivalent static load for non-structural elements has a limitation in that the sloshing effect and the interaction between the fluid and the water tank cannot be considered. In this study, the equations to evaluate the impulse and convective components in the design codes and previous research were compared with the shaking table test results of a rectangular water tank with flexible wall panels. The conclusions of this study can be summarized as follows: (1) It was observed that the natural periods of the impulsive component according to ACI 350.3 were longer than system identification results. Thus, ACI 350.3 may underestimate the earthquake load in the case of water tanks with flexible walls. (2) In the case of water tanks with flexible walls, the side walls deform due to bending of the front and back walls. When such three-dimensional fluid-structure interaction was included, the natural period of the impulsive component became similar to the experimental results. (3) When a detailed finite element (FE) model of the water tank was unavailable, the assumption S_ai = S_DS could be used, resulting in a reasonably conservative design earthquake load.

• 한국소음진동공학회논문집
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• 제13권10호
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• pp.791-797
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• 2003

A liquid storage rectangular tank structures are used In many fields of civil, mechanical and marine engineering. Especially, Ship structures have many tanks In contact with Inner or outer fluid, like ballast, fuel and cargo tanks. Fatigue damages are sometimes observed in these tanks which seem to be caused by resonance with exciting force of engine and propeller. Vibration characteristics of these thin walled tanks in contact with fluid near engine or propeller are strongly affected by added mass of containing fluid. Therefore it is essentially important to estimate the added mass effect to predict vibration of the tank structures. In the previous report, we have developed numerical tool of vibration analysis of 3-dimensional tank structure using finite elements for plates and boundary elements for fluid region. In the present report, using the numerical analysis, vibrations characteristics In deep water tank are investigated and discussed.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.1079-1084
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• 2003

A liquid storage rectangular tank structures are used in many fields of civil, mechanical and marine engineering. Especially, Ship structures have many tanks in contact with inner or outer fluid, like ballast, fuel and cargo tanks. Fatigue damages are sometimes observed in these tanks which seem to be caused by resonance with exciting force of engine and propeller. Vibration characteristics of these thin walled tanks ill contact with fluid near engine or propeller are strongly affected by added mass of containing fluid. Therefore it is essentially important to estimate the added mass effect to predict vibration of the tank structures. In the previous report, we have developed numerical tool of vibration analysis of 3-dimensional tank structure using finite elements for plates and boundary elements for fluid region. In the present report, using the numerical analysis, vibrations characteristics in deep water tank are investigated and discussed.

• 전산구조공학
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• 제9권1호
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• pp.55-64
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• 1996

내부에 사각형 물체가 놓여 있는 사각형수조내 유체의 유동진동수를 선형파이론을 사용하여 산정하였다. 속도포텐셜을 벽체에 의해 발생되는 표면파와 내부물체로 인해 발생되는 반사파, 전달파 및 산란파의 항으로써 표현하였다. 내부물체에 대한 반사율과 전달율은 연속되는 유체영역에서 질량 Flux와 에너지 Flux의 연속조건와 내부물체의 양측면에서의 경계조건을 이용하여 구하였다. 예제해석 결과 유체의 유동진동수는 내부물체가 높고 넓을수록 그리고 물체가 중앙에 가까울수록 감소한다. 내부물체의 크기와 위치의 변화에 의한 유동진동수의 변화는 폭이 수위에 비하여 넓은 수조에서 더욱 민감하다.

• Structural Engineering and Mechanics
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• 제10권6호
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• pp.533-543
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• 2000

To prevent major cracking and failure during earthquakes, it is important to design reinforced concrete liquid storage structures, such as water and fuel storage tanks, properly for the hydrodynamic pressure loads caused by seismic excitations. There is a discussion in recent Codes that most of the base shear applied to liquid containment structures is resisted by inplane membrane shear rather than by transverse flexural shear. The purpose of this paper is to underline the importance of the membrane force system in carrying the base shear produced by hydrodynamic pressures in both rectangular and cylindrical tank structures. Only rigid tanks constrained at the base are considered. Analysis is performed for both tall and broad tanks to compare their behavior under seismic excitation. Efforts are made to quantify the percentage of base shear carried by membrane action and the consequent procedures that must be followed for safe design of liquid containing storage structures.

• 복합신소재구조학회 논문집
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• 제6권2호
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• pp.85-90
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• 2015

The finite element stress analysis of large sized rectangular water tank structures made of stainless steel materials is carried out for various combined load cases. The combined load cases for a large size of 5,000ton are further determined using the specification(KS B6283) established from the Korean Standards Association. The changed water capacity due to the size of reservoirs could be heavily dependent for evaluating seismic effects, especially for large reservoirs. For the better numerical efficiency, the rectangular panels are modelled using the ANSYS ADPL module. The numerical results obtained for different load cases mainly show the effect of the interactions between the different load combination and other various parameters, for example, the water capacity, and different stainless steel materials. The structural performance for various load combinations is also evaluated.