We investigate the stability and control of a plane, laminar jet impinging on a flat plate in a channel, a geometry used to cool down a hot wall with a cold air jet in many industrial configurations. The global stability analysis indicates that, even for a strong confinement, the two-dimensional (2-D) steady flow is unstable to three-dimensional (3-D), steady perturbations. In the simplest limit case where dilatation effects are neglected, we show that the development of the instability induces a significant spanwise modulation of the heat flux at the impacted wall. To control the leading global mode, we propose adjoint-based 3-D harmonic and 2-D steady forcing in the bulk or at the wall. We show for instance that the unstable mode is controllable using a spanwise uniform blowing at the upper wall, in a specific domain corresponding to the footprint of the upper recirculating bubble. These techniques are applied to a novel open-loop control, in which we introduce into the flow a small airfoil, modelled by the lift force it exerts on the flow. © 2010 Springer-Verlag.
CITATION STYLE
Meliga, P., & Chomaz, J. M. (2011). Global modes in a confined impinging jet: Application to heat transfer and control. Theoretical and Computational Fluid Dynamics, 25(1–4), 179–193. https://doi.org/10.1007/s00162-010-0194-6
Mendeley helps you to discover research relevant for your work.