1. 제 목 : Feedback Control of Wall Turbulence with MEMS Sensors/Actuators





2. 연 사 : Professor Yuji Suzuki


Department of Mechanical Engineering


The University of Tokyo





3. 일 시 : 2004년 8월 5일 (목) 16:30 – 17:30





4. 장 소 : 301동 1512호 세미나실





5. 내 용 :


A prototype system for feedback control of wall turbulence is developed, and its performance is evaluated in a physical experiment. Arrayed micro hot-film sensors with a spanwise spacing of 1 mm are employed for the measurement of streamwise shear stress fluctuations, while arrayed magnetic actuators having 3 mm in spanwise width are used to introduce control input through wall deformation. The frequency response of the sensors and actuators is found to be sufficiently high for the flow conditions presently considered. A digital signal processor having a time delay of 0.1 ms is employed to drive output voltage for actuators. Feedback control experiments are made in a turbulent air channel flow using a genetic algorithms-based optimal control scheme.


It is found that the wall shear stress is decreased by 2% with a preliminary non-GA control rule. Second generation feedback control system using 192 sensors and 84 actuators is under development. Attempts to develop sensors having higher response, MEMS wall deformation actuators, and a VLSI analog feedback controller are also discussed.





6. 문 의 : 기계항공공학부 최 해 천 교수 (☏ 880-8361)