Thrust Caused by Oscillating Two-Dimensional Hydrofoil Moving in Propagating Unsteady Flow Field

전파하는 변동유장 중 전진하며 동요하는 2차원 수중 날개에 의한 추력

  • Received : 2012.07.19
  • Accepted : 2012.10.25
  • Published : 2012.10.31


This paper considers a two-dimensional hydrofoil that is fully submerged and oscillating with forward speed. The flow field is assumed to be a propagating vertical velocity field. Using the perturbation theory, the problem is linearized, and the leading-order lift force is surveyed. The thrust force is analytically derived as the second-order horizontal force. As an example, the lift and thrust for a flapping flat plate in heaving and pitching modes are analyzed. The parameters affecting the thrust are listed. The thrust is expressed in terms of the quadratic transfer functions in relation to the disturbances. The quadratic transfer functions are studied parametrically to assess the most favorable thrust.


Thrust;Unsteady flow filed;Oscillating hydrofoil;Analytic approach


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