Responses to disturbance of supersonic shear layer: Input-output analysis

The perturbation dynamics in a supersonic shear layer are characterized using large-eddy simulations and linear-operator-based input-output analysis. The Kelvin-Helmholtz instability emerges as the primary mechanism for disturbance energy amplification. To identify feasible actuator placement locations, we conduct a state-space restricted input-output analysis, revealing the splitter plate trailing surface as the most receptive region. Furthermore, simulations with applied forcing demonstrate that the coherent structures predicted by linear analysis remain active within a highly nonlinear turbulent flow.