Neutral Stability Calculations for Boundary-Layer Flows

An analysis is presented of the parallel neutral stability of three‐dimensional incompressible, isothermal boundary‐layer flows. A Taylor‐series expansion of the dispersion relation is used to derive the general eigenvalues. These equations are functions of the complex group velocity. These relations are verified by numerical results obtained for two‐ and three‐dimensional disturbances in two‐ and three‐dimensional flows.