ADAPTIVE FEEDFORWARD CONTROL OF SMART CFRP-PANELS EXCITED BY A TURBULENT BOUNDARY LAYER

摘要

The objective of this work is the experimental investigation of sound transmission through a smart carbon fiber reinforced plastic (CFRP) panel which is excited by a turbulent boundary layer (TBL) in the acoustic wind tunnel of DLR. The research activities are aimed at the development of a lightweight smart panel with improved low-frequency sound transmission loss for application in future aircraft. The smart panel consists of a CFRP-structure equipped with piezoelectric patch actuators and accelerometers. The control signals are generated by adaptive feedforward-control using single or multiple reference signals and by local and global robust feedback control. Due to the control action, a narrowband sound power level (SWL) reduction greater than 10dB was achieved. The maximum reduction in third-octave band SWL was above 5dB. Continued research on reference sensing and signal processing will further improve the transmission loss of smart lightweight structures under TBL-excitation.