• Title/Summary/Keyword: Contractive and dilative motion

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A Numerical Simulation for Contractive and Dilative Periodic Motion on Axisymmetric Body

  • Kim, Moon-Chan
    • Journal of Ship and Ocean Technology
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    • v.3 no.1
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    • pp.1-11
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    • 1999
  • Numerical simulation for the axisymmetric body with contractive and dilative periodic motion is carried out. The present analysis shows that a propulsive force can be obtained in highly viscous fluid by the contractive and dilative motion of axisymmetric body. An axisymmetric code is developed with unstructured grid system for the simulation of complicated motion and geometry. It is validated by comparing with the results of Stokes approximation with the problem of uniform flow past a sphere in low Reynolds number($R_n$ = 1). The validated code is applied to the simulation of contractive and dilative periodic motion of body whose results are quantitatively compared with the two dimensional case. The simulation is extended to the analysis of waving surface with projecting part for finding out the difference of hydrodynamics performance according to variation of waving surface configuration. The present study will be the basic research for the development of the propulsor of an axisymmetric micro-hydro-machine.

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A Numerical Simulation for the Propulsion of Axisymmetric Micro-Hydro-Machine by Contractive and Dilative Motion (수축팽창 운동에 의한 축대칭 마이크로-하이드로-머신의 추진을 위한 수치 시뮬레이션)

  • Kim Moon-Chan
    • 한국전산유체공학회:학술대회논문집
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    • 2001.05a
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    • pp.30-37
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    • 2001
  • A Numerical simulation for the propulsion of axisymmetric body by contractive and dilative motion is carried out. The present analysis shows that a propulsive force can be obtained in highly viscous fluid by a contractive and dilative motion of axisymmetric body. An axisymmetric analysis code is developed with unstructured grid system for the simulation of complicated motion and geometry. The developed code is validated by comparing with the results of stokes approximation with the problem of uniform flow past a sphere in low Reynolds number($R_n=1$). The validated code is applied to the simulation of contractive and dilative motion of body. The simulation is extended to the analysis of waving surface with projecting part for finding out the difference of hydrodynamic performance according to the variation of waving surface configuration. The present study will be the basic research for the development of the propulsor of an axisymmetric micro-hydro-machine.

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A Numerical Simulation based on Cell-centered Scheme for Contractive and Dilative Motion on Axisymmetric Micro-hydro machine (셀중심법에 의한 축대칭 극소 로봇의 압축팽창운동에 대한 수치적인 연구)

  • 강효길;김문찬;전호환
    • Journal of the Society of Naval Architects of Korea
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    • v.41 no.2
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    • pp.90-97
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    • 2004
  • Flow mechanism of contractive and dilative motion is numerically investigated to obtain a propulsive force in highly viscous fluid. An axisymmetric code is developed with unstructured grid system based on cell-centered scheme. It is validated by comparing with the results of Stokes approximation for the problem of uniform flow past a sphere in low Reynolds number(R$_{n}$=1). The validated code is applied to the simulation of contractive and dilative periodic motion of body whose results are quantitatively compared with the two dimensional case. In order to investigate the grid dependency, two different grids are applied to the present computations. The present study provides key information for the development of an axisymmetric Micro-hydro-robot.t.

Simulation for the Propulsion of Micro-Hydro-Machine with Unstructured Grid (비정규 격자를 이용한 극소 로봇의 추진 해석)

  • Moon-Chan Kim;Dong-Dai Ha
    • Journal of the Society of Naval Architects of Korea
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    • v.39 no.3
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    • pp.1-7
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    • 2002
  • Flow mechanism of contractive and dilative motion is numerically investigated to obtain a propulsive force in highly viscous fluid, which is the simulation of the propulsion in micro-organisms. The computing code for the analysis of complicated motions is developed with cell-centered unstructured grid scheme. The developed code is validated by the well-known problems of cavity flow and oscillating wall. The validated code is applied to the contractive and dilative motion in narrow tube. The computed results are compared with nodal points scheme. By the present results, it is found that propulsive force can be obtained by the contractive and dilative motion through simulation with the developed code.