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Shock curvature and gradients at the tip of pointed axisymmetric bodies in non-equilibrium flow

Published online by Cambridge University Press:  28 March 2006

Raymond Sedney
Affiliation:
Present address: R.I.A.S., 1450 S. Rolling Road, Baltimore, Maryland 21227. Ballistic Research Laboratories, Aberdeen Proving Ground, Md.
Nathan Gerber
Affiliation:
Ballistic Research Laboratories, Aberdeen Proving Ground, Md.

Abstract

The shock curvature and flow variable gradients at the tip of a pointed body caused by non-equilibrium effects are considered. Co-ordinates introduced by Chester (1956) are used since they offer a convenient way of treating the boundary conditions. The desired functions are obtained by solving numerically a system of linear ordinary differential equations. These equations have a singularity; the nature of the singularity is found analytically, and its numerical treatment is discussed. The specific non-equilibrium effect considered is vibrational relaxation in a pure diatomic gas. Representative results are given for flow of N2 over a cone for a comprehensive range of Mach number and cone angle. There is a point analogous to the Crocco point. The exact results are compared with predictions from (i) a hypersonic, small disturbance theory; (ii) the application of an integral method; (iii) characteristic calculations. In an appendix, a comparative discussion is given of results for frozen flow over ogival bodies.

Type
Research Article
Copyright
© 1967 Cambridge University Press

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