Stall-induced fatigue damage in nonlinear aeroelastic systems under stochastic inflow: Numerical and experimental analyses

This study focuses on characterizing the fatigue damage accumulated in nonlinear aeroelastic systems subjected to stochastic inflows through both numerical simulations and wind tunnel experiments. In mathematical model, nonlinearities are assumed exist either structure (via a cubic hardening nonlinearity pitch stiffness), or flow dynamic stall condition), simultaneously structural aerodynamic counterparts. The loads attached conditions estimated using Wagner’s formulation semi-empirical Leishman–Beddoes respectively. To augment findings in-field conditions, oncoming is considered be randomly time-varying nature. input fluctuations modeled Karhunen–Loeve Expansion formulation. response dynamics associated of system, possessing different sources nonlinearities, systematically investigated under isolated cases deterministic flows. Specifically, pertinent role stochasticity brought out by presenting accumulation for values noise intensity time scale fluctuation. It demonstrated that fluctuating intermittently switch between regimes even at low mean speeds. intermittent nature varies as varied. torsional stresses predominant component dictating irrespective source illustrated. Using rainflow counting method Miner’s linear theory, it shown substantially higher compared Importantly, observed scales intensities fluctuation play pivotal systems. Finally, significantly torsionally dominant oscillations dynamical regime regime. strengthened drawing comparisons with preliminary results obtained from experiments performed NACA 0012 airfoil undergoing stall. best our knowledge, this first bridges dichotomy stall-induced signatures maps same corresponding damage. • Role coupled studied. Coupled via stiffness behavior. Effect inflow responses analyzed. Accumulated computed algorithm. Fatigue than conditions.