Publications Details

Quantifying the structural response of a slender cone to turbulent spots at mach 6

Robbins, Brian A.; Casper, Katya M.; Coffin, Peter C.; Mesh, Mikhail M.; Field, Richard V.

A numerical study of the response of a conical structure to periodic turbulent spot loading at Mach 6 is conducted and compared with experimental results. First, a deterministic model which describes the birthing of turbulent spots established by a defined forcing frequency as well as the evolution of the spots is derived. The model is then used to apply turbulent spot loading to a calibrated finite element model of a slender cone structure. The numerical solution yielded acceleration response data for the cone structure. These data are compared to experimental measurement. Similar damping times and acceleration amplitudes are observed for isolated spots. At higher frequencies of turbulent spot generation, the panel response corresponds to the structural natural mode shape being forced; however, only qualitative agreement is observed. Finally, the convection velocity for two cases is varied. It is shown that marginal deviations in the convection velocity of turbulent spots yields little change in the resulting response of a structure. This result illustrates that the time between spot events provides the dominant determination of which structural modes are excited.