Philipp Bekemeyer, Reik Thormann, Sebastian Timme
DOI Number: N/A
Conference number: IFASD-2019-068
Gust load alleviation has become an integral part of aircraft design to significantly decrease the impact of atmospheric turbulence on aircraft loads, handling qualities and also passenger comfort. During the design of an active control system, the aerodynamic response of the aircraft subjected to gust encounter and control surface deflection effects needs to be modelled. Current industrial practice is based on low-fidelity linear-potential panel methods which are repeatedly evaluated in frequency domain to obtain so-called frequency response functions. Even though rapid turnaround times are possible, important aerodynamic effects such as shock waves and resulting boundary layer separation which define transonic flow conditions are neglected. Typically, robust and adaptive control laws have been designed to account for the shortcomings of the underlying aerodynamic modelling fidelity. In contrast to this, we present initial results of a basic gust controller while using an enhanced aerodynamic modelling by solving the linearised Reynolds-averaged Navier–Stokes equations in frequency domain. Results are presented both for an aerofoil and a large aircraft configuration near transonic cruise conditions. Control laws derived from different levels of the aerodynamic hierarchy are scrutinised during unsteady simulations of realistic gust-encounter scenarios.