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Minimum error solutions of the Boltzmann equation for shock structure

Published online by Cambridge University Press:  29 March 2006

R. Narasimha
Affiliation:
Department of Aeronautical Engineering, Indian Institute of Science, Bangalore 12
S. M. Deshpande
Affiliation:
Department of Aeronautical Engineering, Indian Institute of Science, Bangalore 12

Abstract

‘Best’ solutions for the shock-structure problem are obtained by solving the Boltzmann equation for a rigid sphere gas by applying minimum error criteria on the Mott-Smith ansatz. The use of two such criteria minimizing respectively the local and total errors, as well as independent computations of the remaining error, establish the high accuracy of the solutions, although it is shown that the Mott-Smith distribution is not an exact solution of the Boltzmann equation even at infinite Mach number. The minimum local error method is found to be particularly simple and efficient. Adopting the present solutions as the standard of comparison, it is found that the widely used v2x-moment solutions can be as much as a third in error, but that results based on Rosen's method provide good approximations. Finally, it is shown that if the Maxwell mean free path on the hot side of the shock is chosen as the scaling length, the value of the density-slope shock thickness is relatively insensitive to the intermolecular potential. A comparison is made on this basis of present results with experiment, and very satisfactory quantitative agreement is obtained.

Type
Research Article
Copyright
© 1969 Cambridge University Press

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References

Ananthasayanam, M. R. & Narasimha, R. 1968 To appear in Acta Mechanica.
Bauer, F. L., Rutishauer, H. & Stiefel, E. 1962 Proc. Symp. Appl. Math. 15, 199.
Bird, G. A. 1967 J. Fluid Mech. 30, 479.
Camac, M. 1965 Proceedings of the 4th International Symposium on Rarefied Gas Dynamics. Toronto, 1, 240.
Chahine, M. T. & Narasimha, R. 1965 Proceedings of the 4th International Symposium on Rarefied Gas Dynamics. Toronto, 1, 140.
Chapman, S. & Cowling, T. G. 1960 Mathematical Theory of Nonuniform Gases. Cambridge University Press.
Deshpande, S. M. & Narasimha, R. 1969 J. Fluid Mech. 36, 545.
Gustafson, W. A. 1960 Phys. Fluids, 3, 732.
Liepmann, H. W., Narasimha, R. & Chaine, M. T. 1962 Phys. Fluids, 5, 1313.
Lighthill, M. J. 1956 Surveys in Mechanics. Cambridge University Press.
Linzer, M. & Hornig, D. F. 1963 Phys. Fluids, 6, 1661.
Mott-Smith, H. M. 1951 Phys. Rev. 82, 885.
Muckenfuss, C. 1962 Phys. Fluids, 5, 1325.
Narasimha, R. 1966 Phys. Fluids, 9, 2524.
Narasimha, R. 1968 J. Fluid Mech. 34, 1.
Nordsieck, A. & Hicks, B. L. 1967 Proceedings of the 5th International Symposium on Rarefied Gas Dynamics. Oxford, 1, 695.
Oberai, M. M. 1967 J. de Mec. 6, 317.
Rode, D. L. & Tanenbaum, B. S. 1967 Phys. Fluids, 10, 1352.
Rosen, P. 1954 J. Chem. Phys. 22, 1045.
Russell, D. A. 1965 Proceedings of the 4th International Symposium on Rarefied Gas Dynamics. Toronto, 1, 265.
Sakurai, A. 1957 J. Fluid Mech. 3, 255.
Suchy, K. 1963 Proceedings of the 3rd International Symposium on Rarefied Gas Dynamics. Paris, 1, 181.
Watson, G. N. 1944 Theory of Bessel Functions. Cambridge University Press.