• Title/Summary/Keyword: Sloshing phenomena

Search Result 29, Processing Time 0.023 seconds

Numerical study of sway motion of a rectangular floating body with inner sloshing phenomena (내부 슬로싱 현상을 이용한 사각상자 형태의 부유체 Sway 거동 모사에 대한 수치적 고찰)

  • Ha, Minho;Cheong, Cheolung
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2013.04a
    • /
    • pp.161-165
    • /
    • 2013
  • In this paper, possibility of controlling motion of a floating structure using a tuned liquid damper (TLD) is numerically investigated. A TLD is a tank partially filled with liquid. Sloshing phenomena of liquid inside a tank can suppress movement of the tank subject to external excitations at specific frequency. The effects of sloshing phenomena inside a rectangular floating body on its sway motion are investigated by varying excitation frequency. First, a grid-refinement study is carried out to ensure validity of grid independent numerical solutions using present numerical techniques. Then, sway motion of the floating body subjected to wave with five different frequencies are simulated. The normalized amplitudes of sway motion of the target floating body are compared over the frequency, for cases with and without water inside the floating body. It is shown that the motion of the floating body can be minimized by matching the sloshing natural frequency to excitation frequency.

  • PDF

A numerical study on sloshing impact loads in prismatic tanks under forced horizontal motion

  • Parthasarathty, Nanjundan;Kim, Hyunjong;Choi, Yoon-Hwan;Lee, Yeon-Won
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.41 no.2
    • /
    • pp.150-155
    • /
    • 2017
  • Many engineering issues are caused because of sloshing phenomena. Numerical solution methods including the computational fluid dynamics (CFD) technique, are used to analyze these sloshing problems. In this study, a numerical technique was used to analyze sloshing impact loads in a prismatic tank under forced horizontal motion. The volume-of-fraction (VOF) method was adopted to model the sloshing flow. Six cases were used to compare the effects of the natural frequencies of a simple rectangular and prismatic tank, with impact pressure on the prismatic tank wall. This study also investigated the variable pressure loads and sloshing phenomena in prismatic tanks when the frequencies were changed. The results showed that the average of the peak pressure value for ${\omega}^{\prime}1=4.24=4.24$ was 22% higher than that of ${\omega}_1=4.6$.

Numerical simulation of hydroelastic effects of sloshing phenomena in a rectangular tank (사각탱크내의 슬로싱 현상에 기인한 벽면운동에 대한 수치모사)

  • Ha, Minho;Cheong, Cheolung
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2012.10a
    • /
    • pp.534-537
    • /
    • 2012
  • Hydroelastic effects on sloshing phenomena in a rectangular tank are numerically investigated. The dimension of the tank is $1000mm{\times}600mm$, and the filling ratio of water is 20% of tank height. One of the side walls of tank is assumed to be flexible. The tank is excited into sway motion with amplitude of 100mm and frequency of 0.53Hz that is first natural frequency of water inside the tank. Prediction results for time histories of pressure and displacement of flexible and rigid walls are compared to quantitatively assess hydroelastic effects on sloshing phenomena.

  • PDF

Numerical Investigation on Surge Motion of a Rectangular Floating Body due to Inner Sloshing Phenomena (내부 슬로싱 현상에 따른 사각상자 형태의 부유체 서지 거동에 대한 수치적 고찰)

  • Ha, Minho;Cheong, Cheolung
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.23 no.7
    • /
    • pp.662-668
    • /
    • 2013
  • In this paper, possibility of controlling motion of a floating structure using a tuned liquid damper (TLD) is numerically investigated. A TLD is a tank partially filled with liquid. Sloshing motion of liquid inside a tank is known to suppress movement of the tank subject to external excitations at specific frequency. The effects of sloshing phenomena inside a rectangular floating body on its surge motion are investigated by varying external excitation frequency. First, a grid-refinement study is carried out to ensure validity of grid independent numerical solutions using present numerical techniques. Then, surge motion of the floating body subjected to external wave is simulated for five different excitation frequencies of which the center frequency equals to the natural frequency of internal liquid sloshing. The normalized amplitudes of surge motion of the target floating body are compared according to the excitation frequency, for the cases with and without water inside the floating body. It is shown that the motion of the floating body can be minimized by matching the sloshing natural frequency to the excitation frequency.

Analysis of droplet formation under sloshing phenomena in liquid fuel tank (액체 연료 탱크 내 슬로싱 현상에서의 액적 형성 분석)

  • Sungwoo Park;Jinyul Hwang
    • Journal of the Korean Society of Visualization
    • /
    • v.21 no.2
    • /
    • pp.102-110
    • /
    • 2023
  • With the global shift from a carbon-based economy to a hydrogen-based economy, understanding the sloshing phenomenon and its impact on boil-off rate (BOR) in liquid hydrogen (LH2) tank trailers is crucial. Here, we analyze the primary breakup process under sloshing phenomena in a liquid fuel tank. We observe the growth of multiple holes on the sheet-like structures and the formation of ligament structures reminiscent of jet atomization. Through the extraction of three-dimensional liquid regions, we analyze the geometrical characteristics of these regions, enabling the classification of sheets, ligaments, and droplets. The present findings could contribute to understanding the breakup mechanism and hold potential for the development of strategies aimed at minimizing BOR.

Numerical Simulation of Two-dimensional Sloshing Phenomena Using Marker-density Method (밀도함수법을 이용한 2차원 슬로싱 현상의 수치시뮬레이션)

  • Lee, Young-Gill;Jeong, Kwang-Leol;Lee, Seung-Hee
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.46 no.6
    • /
    • pp.650-658
    • /
    • 2009
  • Two dimensional sloshing phenomena in regularly excited liquid cargo tank are numerically simulated with finite difference method. Navier-Stokes equations and continuity equation are computed for this study. The free-surface is determined every time step satisfying kinematic boundary condition using marker-density method. And the exciting force is treated by adding the acceleration of the tank to source term. The results are compared with other existing experiment results. And the comparison results show a good agreement. The sloshing phenomena in the tank of the 138K LNG carrier in sway motion is simulated with present calculation methods in low filling level. To find the relations between impact pressure and excitation condition, the calculations are performed in various amplitudes and periods. The averaged maximum pressures are compared each other.

A NUMERICAL ANALYSIS OF THE SLOSHING IN A TANK WITH PLATE/POROUS BAFFLES (판형 및 다공형 배플을 포함한 탱크 내 슬로싱에 대한 유동해석)

  • Lee, Sang-Hyuk;Hur, Nahm-Keon
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2009.04a
    • /
    • pp.215-222
    • /
    • 2009
  • In the present study, a numerical analysis on the sloshing in a tank with the harmonic motion was investigated. A VOF method was used for two-phase flows inside the sloshing tank and a source term of the momentum equation was applied for the harmonic motion. This numerical method was verified by comparing its results with the available experimental data. The sloshing in a tank causes the instability of the fluid flows and the fluctuation of the impact pressure on the tank. By these phenomena of the tank sloshing, the sloshing problems such as the failure and the noise of system can be generated. For the reduction of these sloshing problems, the various baffles such as the horizontal/vertical plate baffles and the porous baffles inside the tank are installed. With the installations of these baffles, the characteristics of the liquid behavior in the sloshing tank, the impact pressure on the wall, the amplitude of the free surface near the wall and the sloshing noise were numerically analyzed.

  • PDF

Energy dissipation by particle sloshing in a rolling cylindrical vessel (분체슬로싱 현상에 의한 원통형 용기에서의 에너지 소실)

  • Lee, Soo-Hyuk;Heo, Sung-Mo;Cho, Hye-Min;Son, Hyunsung;Jeong, Seong-Min;Park, Junyoung
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.9 no.3
    • /
    • pp.62-68
    • /
    • 2010
  • In the engineering field, sloshing in rolling vessel is a hot issue because of the connection with ship stability problem. The sloshing phenomena also can be utilized in the field of structure or facility vibration damper. This paper explores the possibility which sloshing of multi-particles can be used to dissipate energy in a rolling container. This energy dissipation can be utilized to the application of rotating damper. Some of the parameters expected to dissipates energy, such as vessel size, particle size, mass fraction and ramp height, have been experimentally and theoretically studied.

DEVELOPMENT OF A NUMERICAL SIMULATION METHOD FOR THE ANALYSIS OF SLOSHING PROBLEMS BASED ON CCUP SCHEME (슬로싱 해석을 위한 CCUP 기반 시뮬레이션 기술 개발)

  • Park, J.C.;Hwang, S.C.;Jeong, S.M.
    • Journal of computational fluids engineering
    • /
    • v.16 no.2
    • /
    • pp.1-10
    • /
    • 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.

Seismic behavior of three dimensional concrete rectangular containers including sloshing effects

  • Mirzabozorg, H.;Hariri-Ardebili, M.A.;Nateghi A., R.
    • Coupled systems mechanics
    • /
    • v.1 no.1
    • /
    • pp.79-98
    • /
    • 2012
  • In the present paper, the three-dimensional model of a typical rectangular concrete tank is excited using an artificial and a natural three components earthquake ground motion and the staggered displacement method is utilized for solving the coupled problem of the tank-contained liquid system in time domain. In the proposed method, surface sloshing of the liquid is taken into account in addition to the impulsive term and the appropriate damping values are applied on both of them. The resulted responses are compared with those obtained from the ABAQUS finite element software. It is found that the convective term affects responses extensively and must be considered in seismic design/safety assessment of storage tanks. In addition, the utilized method for solving the coupled problem is stable during the conducted general dynamic analyses and is able to capture the expected phenomena.