Identification of aeroelastic parameters using sweep excitation.

摘要

The method of sweep excitation is employed in the resonance testing of aircraft and other structures. The method allows resonant frequencies and corresponding modal damping parameters to be calculated from a limited amount of real time test data. The amount of test time required to obtain the system's frequency response characteristics is reduced by subjecting the structure to an entire range of frequencies within one test pattern, or "sweep", instead of repeating individual tests at a number of different frequencies. The "sweep-rate" is defined as the rate at which the frequency increases or decreases during the frequency sweep. This thesis studies the effect of sweep-rate and sweep-direction on the accuracy of estimated system parameters, as well as assessing two different methods used to reduce discrete time histories to frequency transfer data. The impact of introducing a structural nonlinearity into the aeroelastic system is also investigated. (Abstract shortened by UMI.)