Response of a Panel Structure Forced by the Noise From a Nearly
نویسنده
چکیده
A model of a high subsonic jet with a nearby array of exible, aircraft-type panels is studied numerically in two dimensions. The jet is excited by a limited duration, spatially localized starter pulse in the potential core. The long time evolution of unsteady disturbances in the jet, the responses of the panels and the ensuing radiation are computed. The results show that the spectral response of both the jet and the panels is concentrated in a relatively narrow frequency band centered at a Strouhal number (based on jet exit velocity) of approximately 0.25 and associated harmonics. The loading on the panels generally increases with downstream distance. Panel radiation is weakest in upstream directions. Interior zones of silence, due to destructive interference of radiation from the panels, are observed. The rst author was supported by NASA Langley Research Center while in residence under a National Research Council Postdoctoral Research Associateship Award. The second author was partially supported by the National Aeronautics and Space Administration under NASA Contract No. NAS1-19480 while in residence at the Institute for Computer Applications in Science and Engineering (ICASE), NASA Langley Research Center, Hampton, VA 23681-0001. Additional support was provided by NSF grant DMS 93-01635.
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متن کاملResponse of a Panel Structure Forced by the Noise from a Nearly Sonic Jet
A model of a high subsonic jet with a nearby array of exible, aircraft-type panels is studied numerically in two dimensions. The jet is excited by a limited duration, spatially localized starter pulse in the potential core. The long time evolution of unsteady disturbances in the jet, the responses of the panels and the ensuing radiation are computed. The results show that the spectral response ...
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