首页|Physical insight into transient hydrodynamics and corresponding flow structures of a pitching hydrofoil via boundary vorticity dynamics

Physical insight into transient hydrodynamics and corresponding flow structures of a pitching hydrofoil via boundary vorticity dynamics

扫码查看
原文链接
  • NETL
  • NSTL
  • Elsevier
© 2024The objective of this study is to investigate the hydrodynamic forces acting on a pitching Clark-Y hydrofoil， with a focus on dynamic flow structures such as boundary-layer separation and vortex evolution， which are driven by the interaction between tangential pressure gradients and on-wall vorticity generation。 Numerical simulations were conducted using the Unsteady Reynolds-Averaged Navier-Stokes (URANS) equations at a Reynolds number of 5 × 104。 Proper Orthogonal Decomposition (POD) was applied to identify the energetic flow modes， while Boundary Vorticity Flux (BVF)-based lift decomposition was further employed to explore the dominant lift contribution。 The results showed that the time-space evolution of the laminar separation bubble (LSB) and trailing-edge vortices (TEVs) experienced a notable delay in formation during the upstroke as the pitching rate increased。 The fluctuating LSB and TEV were extracted as the primary energetic modes。 The dominant lift contributions were found to arise from pressure-gradient-induced vorticity generation on the hydrofoil surface。 Especially， substantial lift fluctuations were traced to concentrated σp peaks downstream of the LSB and alternating peaks at the trailing edge。 Moreover， the delayed onset of LSB bursting and an earlier initiation of trailing-edge separation was attributed to variations in the integral magnitude of σp in the leading and trailing regions。 These insights have direct implications for the design and control of hydrofoil-based systems in marine applications， like underwater control surfaces and hydrokinetic turbines， aiding in the development of strategies to enhance stability and efficiency under dynamic flow conditions。

Boundary layer separationBoundary vorticity fluxPitching hydrofoilTransitionVortices

Hao H.-Y.、Yuan R.、Wu Q.、Huang B.

展开 >

School of Mechanical Engineering Beijing Institute of Technology

2025

10.1016/j.oceaneng.2024.120055

Ocean Engineering

Ocean Engineering

SCI
ISSN：0029-8018
年,卷(期)：2025.317(Feb.1)
  • 22