Passive control of the flow around a hemisphere using porous media

Chloé Mimeau (1) , Iraj Mortazavi (1) , Georges-Henri Cottet (2)

1 CNAM Paris - Centre d'enseignement Cnam Paris
2 EDP - Equations aux Dérivées Partielles

In this work, a passive flow control study is proposed in order to regularize the flow dynamics around a hemisphere at a low and a higher Reynolds number in the wake transition regime. This passive control is realized by covering the projected curved surface of the hemisphere with a porous coating. The presence of such porous medium modifies the boundary conditions at the body-fluid interface, allowing a non-zero velocity to settle in this region. This phenomenon smoothes the global flow dynamics and leads, in particular, to a decrease of the energy dissipation and the aerodynamic force. In this paper, the flow control study is carried out for several configurations using a vortex-penalization technique which allows to easily model solid-fluid-porous media without prescribing any boundary condition.

Mots clés: vortex methods; flow past a hemisphere; passive flow control; porous media; drag reduction; Brinkman penalization method

Domaines: Analyse numérique [math.NA]

Chloé Mimeau, Iraj Mortazavi, Georges-Henri Cottet. Passive control of the flow around a hemisphere using porous media. European Journal of Mechanics - B/Fluids, 2017, 65, pp.213-226. ⟨10.1016/j.euromechflu.2017.03.002⟩. ⟨hal-01483400⟩