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A new approach to problems of shock dynamics Part 2. Three-dimensional problems

Published online by Cambridge University Press:  28 March 2006

G. B. Whitham
Affiliation:
Institute of Mathematical Sciences, New York University

Abstract

This paper gives the extension of the approximate theory developed in Part 1 (Whitham 1957) to three-dimensional problems. The basic equations are derived in §1, using the original assumption of a functional relation between the strength of the shock wave at any point and the area of the ray tube. An analogy with steady supersonic flow is found. For the diffraction of a plane shock wave by an obstacle, the equations and boundary conditions are exactly the same as those for steady supersonic potential flow past that obstacle, with a special choice of the density-speed relation. The successive positions of the shock wave are the equipotential surfaces of the supersonic flow. The 'shock-shocks’ introduced in Part 1, i.e. discontinuities in the slope and Mach number of the shock wave, correspond to the steady oblique shock waves in the supersonic flow problem. They arise when Mach reflexion occurs.

In §2 the theory is applied in detail to the diffraction of a plane shock wave by a cone. Then, in §3, a small perturbation theory is applied to the two typical problems of (i) diffraction by a slender axi-symmetrical body of general shape, and (ii) the stability of a plane shock. Many further applications would be possible and some brief comments on these are made in §4.

Type
Research Article
Copyright
© 1959 Cambridge University Press

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References

Chisnell, R. F. 1957 J. Fluid Mech. 2, 286.
Sears, W. R. (ed.) 1955 General Theory of High Speed Aerodynamics. High Speed Aerodynamics and Jet Propulsion, vol. VI. Princeton University Press.
Ward, G. N. 1955 Linearized Theory of Steady High-Speed Flows. Cambridge University Press.
Weatherburn, C. E. 1931 Differential Geometry, vol. I. Cambridge University Press.
Whitham, G. B. 1952 Comm. Pure Appl. Math. 6, 301.
Whitham, G. B. 1956 J. Fluid Mech. 1, 290.
Whitham, G. B. 1957 J. Fluid Mech. 2, 145.
Whitham, G. B. 1958 J. Fluid Mech. 4, 337.