Numerical Study of Dynamic 2D Bumps for Active Gust Load Alleviation

Abstract

Gust loads on aircraft are critical for structural design. This paper investigates local bump-like modifications in the leading edge region on a generic supercritical airfoil at transonic inflow conditions for the purpose of gust load alleviation. Several parameters are studied to identify a sweet spot for gust load compensation. These include the bump’s height, its streamwise position, its streamwise extension and its oscillation frequency. The evaluations of the URANS simulations reveal that the bumps as investigated in this work are not applicable for compensation of gust induced lift. However, dynamic bumps enable a compensation of approx. 20% of the gust induced pitching moment. A comparison of dynamic bumps with an oscillating trailing edge flap (TEF) and leading edge flap (LEF) reveals the superiority of the flaps for gust load mitigation, especially when a load factor of one is targeted throughout the critical gust event. The qualitative effect of dynamic leading edge bumps on the surrounding flow field is found to be similar to the one caused by oscillating LEF.