Accession Number : AD0687465

Title :   ASYMPTOTIC SOLUTIONS OF NORMAL SHOCK WAVES STRUCTURED BY NONEQUILIBRIUM RADIATIVE AND COLLISIONAL IONIZATION,

Corporate Author : BROWN UNIV PROVIDENCE R I DIV OF ENGINEERING

Personal Author(s) : Clarke,Joseph H. ; Onorato,Michele

Report Date : MAR 1969

Pagination or Media Count : 87

Abstract : Normal shock waves structured by nonequilibrium radiative and collisional ionization are solved analytically. On the basis of current literature, an earlier radiation model for monatomic gases is generalized to include the second continuum with the first continuum and the lines; in the model, the one-step radiative ionization process of interest is interior to a much thicker region only weakly structured by the two-step radiative ionization process. Just downstream of the interior embedded discontinuity, it is assumed that electron-atom collisional ionization to local thermodynamic equilibrium occurs over a length that is small compared with the relevant one-step photon path. It is discovered that the appropriate emmission-convection ratio is also a rather small quantity. Both small quantities lead to iterations studied to second approximation. The resulting shock morphology consists of a strong precursor, the embedded discontinuity, an inner collisional tail, and an outer radiative tail. The interaction of the two small parameters requires certain final reinterpretations. Calculations for helium and argon are presented for a downstream degree of ionization of 0.8, an upstream temperature of 300K, and upstream pressures of .001, .0001, and .00001 atmospheres. (Author)

Descriptors :   (*SHOCK WAVES, NUMERICAL ANALYSIS), NONEQUILIBRIUM FLOW, GAS IONIZATION, THERMODYNAMICS, PHOTONS, APPROXIMATION(MATHEMATICS), INTERACTIONS, HELIUM, ARGON

Subject Categories : Aerodynamics
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE