The impact of shear layer forcing on the recirculating flow past a turbulent bluff body wake is examined. Flow disturbances generated using active and passive devices modify the evolution of the separated flow from the rear edges of a rectangular geometry. A system of pulsed jets with variable frequency allows us to produce unsteady perturbations, whilst passive boundary layer forcing is obtained by spanwise cylinders with variable diameter. Statistics of velocity fields obtained from particle image velocimetry (PIV) are used to quantify the changes in the recirculating flow. Depending on the forcing frequency or perturbation size, the wake balance is modified due to the enhanced mixing along the forced shear flow. The experimental results show that the symmetry properties of the near wake can be controlled by suitable excitation and provide guidelines for the control of wake-related aerodynamic forces exerted on bluff bodies.
|Original language||English (US)|
|Title of host publication||10th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2017|
|Publisher||International Symposium on Turbulence and Shear Flow Phenomena, TSFP10|
|State||Published - 2017|
|Event||10th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2017 - Chicago, United States|
Duration: Jul 6 2017 → Jul 9 2017
|Name||10th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2017|
|Other||10th International Symposium on Turbulence and Shear Flow Phenomena, TSFP 2017|
|Period||7/6/17 → 7/9/17|
Bibliographical noteFunding Information:
The authors acknowledge the support of PSA Peugeot-Citröen in the OpenLab Fluidics (fluidics@poitiers) and warmly thank J.M. Breux and R. Li for fruitful discussions and assistance during the experiments.