A large number of calculations are required for gust loads analyses. Because of this, gust loads analysis methods use a series of assumptions that allow a large number of calculations to be carried out within a short space of time. These include, for example, the assumption of a linear relationship between aerodynamics and structural dynamics, which normally only applies for small deformations. For large deformations and high angles of attack, these methods become less precise, but are normally conservative, so that they can be accepted for design and certification calculations. However, more precise methods are necessary in order to utilise the potential of new technologies for increasing the performance and safety of aircraft.
The Institute’s gust test bed is used for the validation of this method. Experimental and numerical activities go hand in hand for the planning and performance of tests and their evaluations. For the specification of the excitation amplitudes, aeroelastic calculations are carried out in parallel with the experiment.
With the aid of doublet lattice calculations, the entire operating range as well as parameter changes to the model set up can be covered; with coupled CFD / structural simulations, precise predictions can be made with regard to the transfer function for excitation and response amplitudes for a flexible wing.
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