Large-eddy simulations of an autorotating square flat plate

Large-eddy simulation (LES) turbulence models are underdeveloped in the area of fluid-structure interaction (FSI), specifically in autorotation applications. To gain a better understanding of FSI simulations, under the influence of strong turbulent interactions, several LES simulations were conducted to study the autorotation of a thin plate and compared to experimental measurements and RANS simulations found in literature. The plate is allowed to spin freely about its center of mass and is located near the center of a wind tunnel with a free stream velocity of 5 m/s. Wall effects from the wind tunnel enclosure are neglected. In this work, a coupled Computational Fluid Dynamics (CFD) - Rigid Body Dynamics (RBD) model is proposed employing the delayed-detached-eddy simulation (DDES) and the Smagorinsky turbulence models to resolve the subgrid-scale stress (SGS). The qualitative prediction of vortex structures and the qualitative computation of pressure coefficients are in good agreement with experimental results. When compared to RANS, the results from the LES models provide better predictions of the pressure coefficient. Moreover, LES accurately captures the transient behavior of the plate and close correspondence is found between the predicted and measured moment coefficient.