基于单个压电振子的湍流边界层主动控制1.PDF

48 3 Vol. 48 No. 3 2016 5 Chinese Journal of Theoretical and Applied Mechanics May2016 1) 2) (300072) (300072) . 10 . 2 mm Re 2 183 . 25% . O357.5 A doi 101879-15-020 ACTIVE CONTROL OF TURBULENT BOUNDARY LAYER BASED ON A SINGLE PIEZOELECTRIC OSCILLATOR 1) Zhang Hao Zheng Xiaobo Jiang Nan2) (Department of Mechanics School of Mechanical Engineering Tianjin University Tianjin 300072 China) (Tianjin Key Laboratory of Modern Engineering Mechanics Tianjin 300072 China) Abstract Open-loop active control of a turbulent boundary layer has been achieved in skin-friction reduction and sup- pression of coherent structure bursting process by means of periodic oscillating of a piezoelectric oscillator embedded on the surface of a flat plate wall. Ten experimental cases were carried out under variable input voltage amplitudes and frequencies. At 2 mm downstream of the piezoelectric oscillator, the simultaneous time series of streamwise velocity component at dierent wall-normal positions in the turbulent boundary layer were finely measured by