Perturbation wavepackets in a jet, induced by externally applied forcing, are computed from
the linearized equations of motion. An experimentally measured mean flow serves as the
base state for this linear analysis, and optimally amplified mono-frequency perturbations are
identified, in the sense of maximal gain between the forcing energy input and the flow
response energy. Sub-optimal orthogonal forcing/response structures are also discussed.
Linear analysis results are then compared to measured perturbation wavepackets in the jet …

Flow perturbation wavepacket structures arising in response to external forcing are
computed from the linearized equations of motion. An experimentally measured mean flow
serves as base state for this linear analysis, and optimally amplified mono-frequency
perturbations are identified, in the sense of maximal gain between the forcing energy input
and the flow response energy. Results of this linear analysis are then compared to
measured perturbation wavepackets in the jet experiment. The question is to what extent the …