Second Symposium on Turbulence and Shear Flow Phenomena
DOI: 10.1615/TSFP2
ACTIVE CONTROL OF WALL TURBULENCE BY AN ACTUATOR ARRAY PRODUCING SPANWISE PERTURBATIONS
pages 187-192
DOI: 10.1615/TSFP2.310
RÉSUMÉ
Turbulent flow control using an actuator array and related modification of the turbulent spatial structure were experimentally examined using a channel system. Measurements by a particle image velocimeter (PIV) revealed that the actuator array can interact with the low-speed streaks near the wall and the regularity of streak-like coherent structures tends to decrease when the frequency of the wavy motion is more than 12.5 Hz. The critical frequency does not depend on the typical frequency of the burst interval, but may depend on the frequency introduced by the time scale of averaged burst duration.