Abstract
This paper deals with an active feedback control to suppress a flow-induced web flutter using pressure wave. Non-contact suppression of the web flutter by the active feedback control is demonstrated experimentally. In the experiments, a flexible web, as a controlled object, is supported at both ends and subjected to fluid flow in the passage, and a tensile force is applied to the web. The flutter occurs to the web due to the fluid flow with a self-excited feedback mechanism resulting from fluid-structure interaction. The web flutter is suppressed by the active feedback control using the pressure wave from a loudspeaker. The loudspeaker is set at downstream of the passage, and is driven by a control signal with changing the controller gain and phase-shift between the web displacement and control pressure. The ratio of the flutter displacement with control against that without control is examined for various controller gain and phase shift. As a result, it is indicated that the web flutter is effectively suppressed by the proposed active control technique without contact, and the critical flow velocity increases by about 20%.
