Interaction Between a Free Gas Jet and an Upstream-Moving Shock Wave

  • F. Obermeier
  • W. C. Selerowicz
Conference paper


Results of experimental investigations concerning the interaction between a free air jet and an upstream-moving single pressure pulse (shock wave) are presented. It is shown that depending on the jet Mach number a primary single pulse is converted into a cluster of pressure waves. The number of pressure peaks in the cluster increases with the jet velocity. Frequency analysis of pressure signals indicates furthermore a strong dependence of the spectra on the jet velocity. The transformation of the pressure pulse into a cluster of pressure waves is due to the interaction between the flow and shock inside the jet. As a consequence a “xxx” pattern of pressure waves in the jet core is formed while a cluster of pressure waves is generated outside the jet. The use of the obtained results for explaining the frequency behaviour and feedback mechanism of the self-excited oscillations by the free jet — wall interaction is discussed.

Key words

Free jets Shock waves Interactions 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1995

Authors and Affiliations

  • F. Obermeier
    • 1
  • W. C. Selerowicz
    • 2
  1. 1.Max-Planck-Institut für StrömungsforschungGöttingenGermany
  2. 2.Institute of Aeronautics and Applied MechanicsUniversity of TechnologyWarsawPoland

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