Effects of Turbulent Boundary Layer on Panel Flutter

Abstract

Numerical studies were carried out to investigate the effects of turbulent boundary layers on panel flutter at supersonic speeds. In this study, Reynolds-averaged Navier-Stokes equations were solved to take into account the turbulent boundary layer and its viscous effects. First, the fluid-structure coupling code was validated. The computed flutter boundaries agreed well with experimental data. Moreover, the results showed that the viscous effects were important and should be taken into account for flutter computation. Second, the boundary-layer effects were investigated in the Mach number range of 1.0-2.4. We compared the Reynolds-averaged Navier-Stokes computation with the inviscid computation and discussed the differences between them. We found that the boundary layer has not only a stabilizing effect but also a destabilizing effect, depending on the Mach number. The most important finding is that the flutter dynamic pressure slowly increases due to the boundary layer as the Mach number increases. In addition, the design boundary methodology was reviewed in terms of the turbulent boundary-layer effect, which will be helpful for the development of a new boundary-layer correction for the design boundary.