Inviscid instability of an incompressible boundary layer on a compliant surface

The instability of an incompressible boundary layer on a compliant plate with respect to inviscid perturbations is analyzed on the basis of triple-deck theory. It is shown that unstable inviscid perturbations persist only if the inertia of the plate is taken into account. It is found that an important role is played by the bending stiffness of the plate. Specifically, as it approaches a certain value, the instability can become arbitrarily high, but, with a further increase in the bending stiffness, it vanishes completely as soon as the bending stiffness reaches a threshold value.