caa a22 4500 606196935 CHVBK 20210128100927.0 cr unu---uuuuu 210128e20150101xx s 000 0 eng 10.1007/s00348-014-1869-3 doi (NATIONALLICENCE)springer-10.1007/s00348-014-1869-3 Frequency-lock reactive control of a separated flow enabled by visual sensors [Elektronische Daten] [N. Gautier, J.-L. Aider] In this study, a physical-based algorithm is used to control the separated flow downstream of a backward-facing step. It is well known that the spatial extent of the re-circulation bubble can be minimized when acting on the shear layer at the shedding frequency. Using this information in a closed-loop algorithm is not straightforward because of the difficulty of measuring in real time the shedding frequency accurately without disturbing the flow. A novel real-time analysis of 2D velocity fields uses vortex detection to dynamically measure the shedding frequency. Actuation (pulsed jet) is then locked on this frequency. If flow characteristics stray too far from a set point, shedding frequency is updated. The present work demonstrates the efficacy and robustness of this approach in reducing re-circulation, while Reynolds number is randomly varied between 1,400 and 2,400. Springer-Verlag Berlin Heidelberg, 2015 Gautier N. Laboratoire de Physique et Mécanique des Milieux Hétérogènes (PMMH), UMR7636 CNRS, École Supérieure de Physique et Chimie Industrielles de la ville de Paris (ESPCI), 10 rue Vauquelin, 75005, Paris, France aut Aider J.-L Laboratoire de Physique et Mécanique des Milieux Hétérogènes (PMMH), UMR7636 CNRS, École Supérieure de Physique et Chimie Industrielles de la ville de Paris (ESPCI), 10 rue Vauquelin, 75005, Paris, France aut Experiments in Fluids Springer Berlin Heidelberg 56/1(2015-01-01), 1-10 0723-4864 56:1<1 2015 56 348 https://doi.org/10.1007/s00348-014-1869-3 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00348-014-1869-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Gautier N. Laboratoire de Physique et Mécanique des Milieux Hétérogènes (PMMH), UMR7636 CNRS, École Supérieure de Physique et Chimie Industrielles de la ville de Paris (ESPCI), 10 rue Vauquelin, 75005, Paris, France aut NATIONALLICENCE 700 1- Aider J.-L Laboratoire de Physique et Mécanique des Milieux Hétérogènes (PMMH), UMR7636 CNRS, École Supérieure de Physique et Chimie Industrielles de la ville de Paris (ESPCI), 10 rue Vauquelin, 75005, Paris, France aut NATIONALLICENCE 773 0- Experiments in Fluids Springer Berlin Heidelberg 56/1(2015-01-01), 1-10 0723-4864 56:1<1 2015 56 348