Gust response of a flexible typical section via high- and (tuned) low-fidelity simulations

• Low-and high-fidelity gust responses of a flexible typical section.
• Analytical and numerical fluid–structure interaction models compared.
• Low-and high-fidelity results agree well for attached aerodynamic flow.
• Low-and high-fidelity results do not agree for separated aerodynamic flow.
• Low-fidelity model tuning and dynamic stall model are recommended.

The gust response of a flexible typical section is investigated in term of both high- and low-fidelity simulations, in order to assess the suitability of the two approaches in the preliminary Multidisciplinary Design and Optimisation (MDO) of flexible wing aerofoils. A vertical wind gust acts as the aerodynamic perturbation to the static equilibrium of the typical section, the dynamic response of which is formulated as a fluid–structure interaction (FSI) problem in the subsonic regime and computed for a “1-COS” gust profile having different intensities. The low-fidelity response is calculated using a (tuned) theoretical model, whereas the high-fidelity one is obtained using the commercial tool ADINA, where both k − ω and k − ∊ turbulence models are employed. The effects of the physical differences between the high- and low-fidelity models are identified in the aerofoil response for the case of either weak or strong travelling gust, where the influence of the aerofoil on the latter is accounted for in the high-fidelity simulations only. Both thin and thick aerofoils are considered and the low-fidelity results agree well with the high-fidelity ones for the case of weak gust and attached aerodynamic flow, whereas the opposite is true for the case of strong gust and separated aerodynamic flow.