Abstract: The arbitrary vibration motion of a wing around its reference state is expanded into Fourier series of n harmonic waves with different amplitudes and frequencies. The unsteady aerodynamic load due to each harmonic motion is calculated by the Green′s function method; by superposing them in the time domain. The unsteady aerodynamic loads of the given vibration motion are obtained. Much discussion is given on the unsteady aerodynamic loads caused by approximately square waves motion. Numerical examples show that the results of the present method are in good agreement with the results of other methods and experimental data.

Key words: Four ier series, unsteady aerodynamics, Greencs function, numerical analysis