Numerical Calculation Of A Tiltrotor Aircraft Aerodynamic Stability Derivatives

Abstract

The present paper is aimed to investigate the capability of mid-fidelity aerodynamic solvers to perform a preliminary evaluation of static and dynamic stability derivatives on tiltrotor aircraft configurations during their design phase. In this work, the mid-fidelity aerodynamic solver DUST based on vortex particle method (VPM) was used to perform simulations in static and dynamic motion conditions of the Bell XV-15 tiltrotor aircraft. Static simulations allowed for the calculation of static stability derivatives, while dynamic simulations, using two different approaches applied to the time history of the load in a dynamic motion, enabled the calculation of dynamic derivatives. The entire procedure was carried out following a 'breakdown' approach, with the goal of highlighting the interactions between different aircraft's components (such as wing-tail and rotor-airframe), and to provide an approach for the overall assessment of Stability & Control characteristics of the aircraft. The limited computational effort required by the mid-fidelity aerodynamic approach represents an effective trade-off in obtaining fast and accurate solutions that can be used for the preliminary design of novel rotary-wing vehicle configurations.