Analysis Regarding the Effects of Atmospheric Turbulence on Aircraft Dynamics

摘要

This paper will analyze the Gust Load Alleviation (GLA) systems which can be used to reduce the effects of atmospheric turbulences generated by wind gusts on vertical acceleration of aircraft. Their purpose is to reduce airframe loads and to improve passenger comfort. The dynamic model of the aircraft is more realistic than a rigid-body model, since it includes the structural flexibility; due to its complexity, such model can make feedback control design for gust load alleviation more challenging. The gust is generated with the Dryden power spectral density model. This kind of model lends itself well to frequency-domain performance specifications in the form of the weighting functions. Two classical analytical representations for the power spectral density (PSD) function of atmospheric turbulence as given by Von Kármán and Dryden, were used. The analysis is performed for a set of specified values for flight velocity and altitude (as test cases), with different gust signals that must be generated with the required intensity, scale lengths and PSD functions.