Visualization of vibration mode of the single layer CFRP plate by the super-directional loudspeaker

Abstract

This study performs to evaluate the usefulness of the super-directional loudspeaker in visualizing the vibration mode of single-layer CFRP thin plate. Vibration mode of single-layer CFRP thin plate is excited by acoustic excitation. In order to confirm the vibration mode of the single-layer CFRP thin plate, the laser doppler velocimeter and a time-averaged digital holographic interference device are produced. These devices are able to find the natural frequency and vibration modes of the plate in the same time. In the experiment, it was confirmed that deformation of the torsional vibration of the single-layer CFRP thin plate is affected by positional relationship of the single-layer CFRP thin plate and loudspeaker. In addition, acoustic excitation with super-directional loudspeaker was confirmed that can efficiently measure the vibration mode of the single-layer CFRP thin plate as compared with the conventional.