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Updated: May 14, 2026

Visualization of High Speed Liquid Jet Impaction on a Moving Surface
Published on: April 17, 2015
Near-field shock formation in noise propagation from a high-power jet aircraft
Kent L Gee1, Tracianne B Neilsen, J Micah Downing
1Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602, USA. kentgee@byu.edu
Abstract:
Noise measurements near the F-35A Joint Strike Fighter at military power are analyzed via spatial maps of overall and band pressure levels and skewness. Relative constancy of the pressure waveform skewness reveals that waveform asymmetry, characteristic of supersonic jets, is a source phenomenon originating farther upstream than the maximum overall level. Conversely, growth of the skewness of the time derivative with distance indicates that acoustic shocks largely form through the course of near-field propagation and are not generated explicitly by a source mechanism. These results potentially counter previous arguments that jet "crackle" is a source phenomenon.
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