Multibody Simulation of Flexible Aircraft With Variable Sweep Wingtips

This is the authors' abstract. We don't add key points for this paper.

An investigation into variable sweep wingtips for use on flexible aircraft is presented. A suitable flexible multibody formulation is first developed, which includes a formulation for a prescribed rotation joint between flexible beam elements. This allows for the simulation of dynamic actuated wingtips, for use within an aeroelastic simulation framework. A novel implementation is demonstrated, using an automatic differentiation approach to computing derivatives, allowing for a very convenient implementation for a range of multibody constraints. The use of the unsteady vortex lattice method for modelling swept wings where the paneling is misaligned with the flow is also investigated, all combined to give an analysis tool for flexible aircraft dynamics with swept wingtips. Numerical results on representative configurations investigate the potential advantages of this unconventional solution, with gust load alleviation from sweeping back the wingtips observed when compared to the reference configuration. Lastly, it was found that there are potential uses for dynamically sweeping the wingtips in flight, with a roll and pitching maneuver being demonstrated using opposing and symmetric sweep respectively.