Planar shock cylindrical focusing by a perfect-gas lens

P. E. Dimotakis*, Ravindra Samtaney

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

39 Scopus citations

Abstract

We document a gas lensing technique that generates a converging shock wave in a two-dimensional wedge geometry. A successful design must satisfy three criteria at the contact point between the gas lens and the wedge leading edge to minimize nonlinear reflected and other wave effects. The result is a single-point solution in a multidimensional parameter space. The gas lens shape is computed using shock-polar analysis for regular refraction of the incident shock at the gas lens interface. For the range of parameters investigated, the required gas-lens interface is closely matched by an ellipse or hyperbola. Nonlinear Euler simulations confirm the analysis and that the transmitted shock is circular. As the converging transmitted shock propagates down the wedge, its shape remains nearly uniform with less than 0.1% peak departures from a perfect circular cylinder segment. Departure from the design criteria leads to converging shocks that depart from the required shape. The sensitivity to incident shock Mach number, as well as the qualitative effects of the presence of boundary layers are also discussed.

Original languageEnglish (US)
Article number031705
JournalPhysics of Fluids
Volume18
Issue number3
DOIs
StatePublished - Jan 1 2006

Keywords

  • Aerodynamics
  • Boundary layers
  • Flow simulation
  • Mach number
  • Shock waves

ASJC Scopus subject areas

  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'Planar shock cylindrical focusing by a perfect-gas lens'. Together they form a unique fingerprint.

Cite this