Evolution of resonant wave triads in three-dimensional boundary layers

An analysis is presented that examines the modulation of different instability modes satisfying the triad resonance condition in time and space in a three-dimensional boundary-layer flow. Detuning parameters are used for the wavenumbers and the frequencies. The nonparallelism of the mean flow is taken into account in the analysis. At the leading-edge region of an infinite swept wing, different resonant triads are investigated that are comprised of traveling crossflow, stationary crossflow, vertical vorticity, and Tollmien-Schlichting modes. The spatial evolution of the resonating triad components are studied.