Numerical simulation results are presented for subsonic flow oscillation in a plane stator airfoil cascade excited by the incident periodic wake system that is induced by an upstream rotor cascade and uniformly moving along stator cascade front. The model includes harmonic analysis of 2-dimensional unsteady perturbation field that is generated by this interaction in the incident flow. Numerical results of such investigation show that among different frequency-mode components of generated acoustic perturbation field the dominating components are those that for given velocity of the wake system moving along the stator cascade front are found near their cut-off frequency values. Under such conditions, considerable increase of the corresponding frequency components of the unsteady aerodynamic load on airfoils of rotor and stator cascades occurs.
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