Physics of the Ejectors

  • Giuseppe Grazzini
  • Adriano Milazzo
  • Federico Mazzelli


The global behavior of the ejector results from a combination of complex flow features including shock trains, turbulent mixing layers bounded by wall regions, shock-induced separations, boundary layers subject to adverse pressure gradients, non-equilibrium phase change, etc. It is because of this complexity that ejector design and performance have thus far been difficult to characterize and optimize.

In what follows, a brief review of the main physical phenomena occurring in a supersonic ejector will be described, and some relations will be introduced. These findings will be further exploited in Chap. 3 when some design tools will be described.


Working fluid Expansion and compression Compressible mixing Phase change 


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Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  • Giuseppe Grazzini
    • 1
  • Adriano Milazzo
    • 1
  • Federico Mazzelli
    • 1
  1. 1.Department of Industrial EngineeringUniversity of FlorenceFlorenceItaly

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