Experimental Characterization of High-Amplitude Fluid-Structure-Interaction of a Flexible Hydrofoil at High Reynolds Number

A fluid-structure-interaction (FSI) experiment was designed and executed with a focus on producing low-frequency (~10 Hz), high-amplitude ($\pm$3.5% of the span) fin motion. This was achieved by placing a backward facing swept fin at -9.6{\deg} angle-of-attack within the wake of a roughened cylinder. Test section speeds between 2.5 and 3.6 m/s produced cylinder diameter based Reynolds numbers between 190,000 and 280,000, respectively. Detailed descriptions of the tunnel and model geometry, material/structural behavior, fluid properties and initial conditions are provided to facilitate development of FSI models. Given the initial conditions, the resulting forced fin behavior was characterized with measurements of the mean and fluctuating components of the flow upstream of the fin (i.e. within the cylinder wake), fin-tip/surface motion and the fin constraint loading. This work provides a high fidelity experimental dataset of a challenging flow that will require two-way coupling in FSI models to properly capture the resulting behavior. Thus this rich dataset can be used by modelers to identify strengths and weaknesses of various FSI modeling approaches.