MODEL OF THE UNSTEADY AERODYNAMIC CHARACTERISTICS AT HIGH AOA WITH NONLINEAR DEPENDENCY IN ANGULAR RATE

摘要

Experimental study of unsteadyaerodynamic characteristics of a passengeraircraft over an extended angle-of-attack rangewas carried out using a series of forcedoscillationtests. Strong nonlinear effects,namely, an influence of oscillation frequency onaerodynamic derivatives and hysteresises withmultiple self-intersections, were observed. Theexperimental results enable an influence of apitch rate on unsteady pitch moment to beanalyzed. A model of unsteady aerodynamiccharacteristics with Nonlinear Dependency inAngular Rate (NDAR) describing the maindynamic effects observed in the experiment wasdeveloped. The proposed model is comparedwith linear, state-space and neural networkmodels.