Global receptivity analysis: physically realizable input–output analysis

In the context of transition analysis, linear input-output analysis determines worst-case disturbances to a laminar base flow based on generic right-hand-side volumetric/boundary forcing term. The is not physically realizable, and, our knowledge, framework for posing physically-realizable disturbance problems lacking. natural receptivity are forced by matching (typically local) solutions within boundary layer outer consisting free-stream vortical, entropic, and acoustic disturbances. We pose scattering formalism restrict input set realizable associated with plane-wave problem. formulation validated comparing direct numerical simulations (DNS) Mach 4.5 flat-plate layer. show that method provides insight into mechanisms identifying those combinations maximize energy amplification over range frequencies. also discuss how can be extended accommodate from shocks in shock layers supersonic flow.