Assessment and optimization of dynamic stall semi-empirical model for pitching aerofoils

Assessment and optimization of dynamic stall semi-empirical model for pitching aerofoils

Enrico Galli, Gregorio Frassoldati, Davide Prederi, Giuseppe Quaranta

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Abstract. Dynamic stall is a phenomenon affecting aerofoils in unsteady flows which is particularly relevant in the helicopter field. Semi-empirical models are reliable tools to simulate this phenomenon, especially during preliminary design phases and for aeroelastic assessments. However, they need a large number of tuning parameters to provide reliable estimations of unsteady airloads. To face this problem, a parameter identification procedure based on sequential resolutions of optimization problems by means of a Genetic Algorithm is developed and it is applied to the state-space formulation of a modified version of the so-called “Second Generation” Leishman-Beddoes model. The effects of the optimal parameters on the model prediction capabilities are discussed and the variability of the parameters with reduced frequency is studied. The estimations of the unsteady airloads obtained by applying the optimization of parameters show a great improvement in the correlation of the experimental data if compared to the predictions obtained by using the parameters provided in literature, especially for pitching moments where the negative peaks are very well described. These improvements justify the need for optimization to set the parameters.

Dynamic Stall, Helicopter Rotors, Optimization

Published online 11/1/2023, 5 pages
Copyright © 2023 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: Enrico Galli, Gregorio Frassoldati, Davide Prederi, Giuseppe Quaranta, Assessment and optimization of dynamic stall semi-empirical model for pitching aerofoils, Materials Research Proceedings, Vol. 37, pp 156-160, 2023


The article was published as article 34 of the book Aeronautics and Astronautics

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