Experimental investigation of the fluid-structure interaction between a flexible plate and a periodic gust by means of Robotic Volumetric PIV

In the present work Robotic Volumetric PIV is applied in a Fluid-Structure Interaction (FSI) investigation. The case studied involves the dynamic response of a flexible aluminium plate subjected to gust excitation. The experiment is carried out in the Open Jet Facility at Delft University of Technology, which is equipped with a gust generator. Phase-averaged structural displacement of the entire plate together with the volumetric near flow field is measured, with a total measurement volume of approximately 150 litres. Small circular markers are applied to the surface of the plate in order to carry out the structural measurement, which is validated by means of a Scanning Vibrometer. The assessment of the FSI phenomenon is conducted at a wind-tunnel speed of 12 m/s and at a reduced frequency of 0.045. The main aim of this experimental investigation is to demonstrate the capability of Robotic Volumetric PIV to deliver unprecedented quantitative volumetric flow visualization coupled to structural displacement measurement at large scales. The challenges faced to achieve such an objective include the possibility to distinguish between flow particles and structural markers in the acquired images, the validity of the structural displacements measured by the PIV system, the feasibility of the phase-average approach and the consistence of the combined structural and flow information. A visualization of the FSI phenomenon is presented, together with a quantitative analysis of its dynamics.