• 한국기계가공학회지
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• 제10권4호
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• pp.31-37
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• 2011

Fuel tank sloshing noise of vehicle is caused by flow impact on the tank wall during sudden braking, and the sloshing vibration of tank wall is a coupled phenomenon of the fuel inside tank and tank wall structure. Therefore, Fluid-Structure Interface(FSI) analysis technology should be adopted to predict accurately the sloshing vibration. In this study, FSI approach was employed to analyze sloshing phenomenon for a simple tank model with velocity change of the actual vehicle test. First, the simulated results for rigid tank model were compared with those for deformable tank model. Next, influence of baffle location and shape of baffle holes on the acceleration magnitude and the maximum stress of tank wall was investigated. In addition, sloshing analysis for tank with another baffle type was carried out.

• Coupled systems mechanics
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• 제4권4호
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• pp.317-336
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• 2015

The present paper deals with the analysis of water tank with elastic separator wall. Both fluid and structure are discretized and modeled by eight node-elements. In the governing equations, pressure for the fluid domain and displacement for the separator wall are considered as nodal variables. A method namely, direct coupled for the analysis of water tank has been carried out in this study. In direct coupled approach, the solution of the fluid-structure system is accomplished by considering these as a single system. The hydrodynamic pressure on tank wall is presented for different lengths of tank. The results show that the magnitude of hydrodynamic pressure is quite large when the distances between the separator wall and tank wall are relatively closer and this is due to higher rotating tendency of fluid and the higher sloshed displacement at free surface.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계 학술대회논문집(수송기계편)
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• pp.65-68
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• 2005

In this paper, a theoretical study is carried out on the hydroelastic vibration of a rectangular tank wall. It is assumed that the tank wall is clamped along the plate edges. The fluid velocity potential is used for the simulation of fluid domain and to obtain the added mass due to wall vibration. In addition, the vibration characteristics of stiffened wall of the rectangular tank are investigated. Assumed mode method is utilized to the stiffened plate model and hydrodynamic force is obtained by the proposed approach. The coupled natural frequencies are obtained from the relationship between kinetic energies of a wall including fluid and the potential energy of the wall. The theoretical result is compared with the three-dimensional finite element method and then added mass effect is discussed due to tank length and potential mode.

• Structural Engineering and Mechanics
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• 제89권4호
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• pp.421-436
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• 2024

This research addresses experimentally the relationship between the excitation frequency and both hoop and axial wall stresses in a water storage tank. A low-density polyethylene tank with six different aspect ratios (water level to tank radius) was tested using a shake table. A laminar box with sand represents a soil site to simulate Soil-Structure Interaction (SSI). Sine excitations with eight frequencies that cover the first free vibration frequency of the tank-water system were applied. Additionally, Ricker wavelet excitations of two different dominant frequencies were considered. The maximum stresses are compared with those using a nonlinear elastic spring-mass model. The results reveal that the coincidence between the excitation frequency and the free-vibration frequency of the soil-tank-water system increases the sloshing intensity and the rigid-like body motion of the system, amplifying the stress development considerably. The relationship between the excitation frequency and wall stresses is nonlinear and depends simultaneously on both sloshing and uplift. In most cases, the maximum stresses using the nonlinear elastic spring-mass model agree with those from the experiments.

• 한국안전학회지
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• 제11권1호
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• pp.75-83
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• 1996

This paper was concerned with pool fire about many used kerosene and diesel oil. In order to know the thermal effects of kerosene and diesel oil, temperature change in the pool fire of these fuels were obtained as a variation of combustion time and the tank's height and diameter by using the data acquisition system, And fuel combustion velocity were derived as a function of the diameter and wall thickness of tanks and combustion time. As a result, when the tank's height was 15㎝, the greater diameter the higher temperature rising regardless of tank's wall thickness and fuels. But, when the tank's height is 30㎝, temperature rising was not higher than 15㎝. Also, temperature rising in the pool fire of kerosene much higher than diesel oil. Kerosene's combustion velocity was about two times faster than diesel oil. And, kerosene's combustion velocity was increased according to the increasing of tank's diameter and combustion time. But, diesel oil's combustion velocity was a little increased or not. Surrounding temperature change of tank with the pool fire was obtained temperature distribution of 0∼35℃ according to the change of tank's diameter and distance from the tank's wall.

• Journal of Advanced Marine Engineering and Technology
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• 제34권5호
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• pp.718-724
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• 2010

공동수조와 예인수조에서의 프로펠러 단독특성 차이를 보정할 수 있는 위벽효과 연구를 수행하였다. 우선 공동수조의 실험에서 프로펠러의 상류가 아닌 작동 평면 위치에서 계측된 유속을 프로펠러 전진속도로 정의할 경우, 위벽효과의 수정 량 및 단독특성차이가 현저히 줄어드는 것을 확인하였다. 다음으로 양력판 이론에 의한 단독특성 계산을 통해, 프로펠러 평면에서의 위벽효과를 구하고 앞의 결과에 추가적인 보정을 수행하였다. 그 결과, 예인수조에서의 단독특성과 더욱 더 좋은 일치를 보여 주는 것을 확인하였다.

• 한국가스학회지
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• 제12권4호
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• pp.14-20
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• 2008

본 논문에서는 멤브레인 내부탱크, 합판, PUF 보냉재, 또 다른 합판, 예응력 콘크리트(PC) 구조물로 건설된 LNG 저장탱크의 강도안전성을 4가지의 누설해석 파괴모델에 대해 수치적으로 해석하였다. $200,000\;m^3$의 저장용량을 갖는 탱크벽면을 통한 LNG의 누설기준은 열저항 온도해석의 핵심이론이다. 결국 누설 LNG의 초저온 온도가 외부탱크의 외측벽면에서 검출되면, 이것은 저장탱크의 벽면두께를 통해 누설되었다고 가정할 수 있다. 열저항법에 기초한 누설안전성 해석결과에 의하면 합판이나 PUF 등은 벽면을 통해 누설하는 LNG를 차단할 수 있지만, 이들 벽면은 누설 LNG의 압력에 의해 파괴되므로 누설안전성을 보장하지 못한다. 그러나, PC 외부탱크는 누설된 LNG 압력을 접해도 초기에는 견디지만, 시간이 경과하면서 누설된 LNG가 탱크벽체 내부로 계속 스며들어 벽체의 온도가 급격하게 떨어지면서 누설은 진행될 것으로 예상된다. 따라서 PC 외부탱크는 누설 LNG를 일정기간 체류시켜 LNG의 누설기간을 연장하는 효과를 제공할 뿐이다.

• 대한설비공학회지:설비저널
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• 제16권4호
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• pp.406-414
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• 1987

As one of the explosion suppression methods of LPG tank exposed to hot environment by an accident or fire, some material which has large heat capacity and thermal conductivity can be installed inside the LPG tank in order to suppress the temperature increasement of tank wall. In the present study, theoretical model for the horizontally locating cylindrical LPG tank with and without the aluminum explosion suppression material has been developed to predict the characteristics of system. As a parametric study, effects of two major parameters, thickness of material filling and initial vapor volume fraction, on the time variation of wall temperature, temperature and pressure in tank are numerically examined. The results of present study show that the thickness of material filling does not give big differences in the suppression characteristics when the thickness of filling is larger than three inches. In case of material filling, there are marked suppression effects to the increase-ment of wall temperature, average vapor temperature and pressure in tank compared with the case of no filling.

• 한국유체기계학회 논문집
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• 제7권6호
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• pp.55-61
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• 2004

A numerical procedure for optimizing the shape of three-dimensional sedimentation tank is presented to maximize its sedimentation efficiency. The response surface based optimization is used as an optimization technique with Reynolds-averaged Navier-Stokes analysis for multi-phase flow. Standard $k-{\epsilon}$ model is used as a turbulence closure. Three design variables such as, tank height to center feed wall diameter ratio, blockage ratio of center feed wall and angle of distributor are chosen as design variables. Sedimentation efficiency is defined as an objective function. Full-factorial method is used to determine the training points as a means of design of experiment. Sensitivity of each design variable on the objective function has been evaluated. And, optimal values of the design variables have been obtained.

• 한국안전학회지
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• 제19권1호
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• pp.88-93
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• 2004

This experimental study was carried out to evaluate effect of the radiation heat flux for the pool and spill fire in petroleum storage tanks, which were made form steel. Each of them had the capacity of 250, 2500 and 25000 liter, respectively. The effects of the radiation heat flux are as follows; 1) The intensity of radiation heat flux from a flame decreased exponentially with increasing distance from outside wall of tanks, and increased significantly with surface area of tank and dyke. 2) In the case of 25000L tank, the radiation heat flux was about max. 98.9kW/$m^2$ in 1m from wall of tank. 3) The distance, that was able to ignite wood or plastics by radiation heat flux of approximately 12.5kW/$m^2$, was about 3.14m from wall of 25000L tank.