Internal flows with multiple sonic points

  • G. H. Schnerr
  • P. Leidner
Part of the Acta Mechanica book series (ACTA MECH.SUPP., volume 4)


In real gas flow several effects are inverted if the fundamental gasdynamic derivative Γ becomes negative. Here we investigate stationary flows with multiple sonic points. In a nozzle with two throats three sonic points occur where the first or the last is related with the absolute maximum of the mass flux density; the location of this absolute maximum depends on the reservoir state. Then we calculate 2-D flows in a circular arc nozzle by solving the Euler equation with a time dependent finite volume method (FVM) of Jameson. For a high exit pressure (p e /p 01 = 0.94) two sonic shocks occur whereas the flow remains entirely subsonic in between. In order to demonstrate nonclassical effects in strongly bended channels we present results of potential vortex flow of dense gases. Here we observe the formation of separated circular ring shaped supersonic and subsonic regions in the interior of the vortex.


Mach Number Sound Speed Reservoir State Organic Rankine Cycle Nozzle Flow 
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Copyright information

© Springer-Verlag 1994

Authors and Affiliations

  • G. H. Schnerr
    • 1
  • P. Leidner
    • 1
  1. 1.Institut für Strömungslehre und StrömungsmaschinenUniversität Karlsruhe (TH)KarlsruheFederal Republic of Germany

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