Highly Flexible Aircraft Flight Dynamics using CFD

The present paper focuses on the development of a numerical CFD methodology for the simulation of the flight dynamics of the flexible aircraft, in open loop and in closed loop as well. To do so, a modular environment is developed to couple the ONERA CFD solver elsA with Python modules implementing several simulation capabilities: prescribed complex trajectory, 6 DoFs flight dynamics, structural linear dynamics, control surfaces actuations, control laws. The basic assumptions and numerical features of the developed environment are presented along with a reminder of the unsteady deformable capabilities of the elsA code, and several applications performed in the frame of the French DGAC funded MAJESTIC project on the HAR XRF1 configurations are shown. In particular the topic of the simulation of active Gust Load Alleviation is examined. Perspectives are given on the future extension of the approach to the accounting for non-linear structural behaviour, and the possible use of other CFD solver such as CODA or the ONERA next generation solver SoNICS.