Phase-averaged mean properties of turbulent flow developing, around a fluttering sheet of net

Elkhadim Bouhoubeiny , Philippe Druault (1) , Grégory Germain

1 IJLRDA-MPIA - Modélisation, Propagation et Imagerie Acoustique

Time-Resolved Particle Image Velocimetry (PIV) measurements are performed to investigate the hydrodynamic flow interaction with a representative piece of fishing net structure. Using the advanced post-processing mathematical tool based on Proper Orthogonal Decomposition, the phase averaged mean properties of turbulent flows are extracted from Ply database, demonstrating the existence of a Turbulent Boundary Layer (TBL) flow developing all around the sheet of net. The results also show that the mesh opening and so the turbulent flow passing through the structure are strongly influenced by the structure oscillations. This work allows us to demonstrate that the drag computation of fishing gear, commonly based on uniform velocity, needs to consider not only the local velocity deficit near the horizontal part of the net but also the instantaneous oscillations of the sheet of net.

Mots clés: Fishing net structure; Hydrodynamics; PIV; Turbulent boundary layer flow

Domaines: Biomécanique [physics.med-ph]; Acoustique [physics.class-ph]

Elkhadim Bouhoubeiny, Philippe Druault, Grégory Germain. Phase-averaged mean properties of turbulent flow developing, around a fluttering sheet of net. Ocean Engineering, 2014, 82, pp.160-168. ⟨10.1016/j.oceaneng.2014.03.009⟩. ⟨hal-01459730⟩