Hostname: page-component-848d4c4894-pjpqr Total loading time: 0 Render date: 2024-06-29T05:35:23.540Z Has data issue: false hasContentIssue false

Observation of ‘switch-on’ shocks in a magnetized plasma

Published online by Cambridge University Press:  13 March 2009

A. D. Craig
Affiliation:
U.K.A.E.A. Culham Laboratory, Abingdon, Berkshire
J. W. M. Paul
Affiliation:
U.K.A.E.A. Culham Laboratory, Abingdon, Berkshire

Abstract

The Charybdis experiment is designed to produce shock waves propagating into a magnetized hydrogen plasma in directions parallel and almost parallel to the initial field and, in particular, the ‘switch-on’ shock. An initial plasma

is produced in a pyrex chamber (0.46 m dia., 125 m long) containing an axial magnetic field (Bz up to 0.28 T): a magnetic piston is produced by a fast-rising radial discharge between a short central and an annular outer electrode at one end of the chamber; the Lorentz force on the current sheet causes axial propagation, and under certain conditions a curved shock front propagates ahead of the piston. The Alfvén Mach number of the flow is varied by changing the axial field strength: at high Mach number, where a parallel shock should be gas dynamic, no separated shock is found; at low Mach number, where theory predicts‘switchon’ shock behaviour, a clearly separated curved shock front is found which passes through a point of parallel propagation. Magnetic and electric probe measurements at the point of parallel propagation show the presence of a ‘switchon’ shock. It is suggested that the ‘switch-on’ and adjacent oblique shocks are matched together by an intermediate wave propagating behind the latter and merging with the former.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1973

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Alikhanov, S. G., Alinovsky, N. I., Dolgov-Savelev, G. G., Eselevich, V. G., Kurt-Mullaev, R. Kh., Malinovsky, V. K., Nesterikhin, Yu. E., Pilsky, V. I., Sagdeev, R. Z. & Semenov, V. N. 1968 Proc. 3rd int. Conf. on Plasma Physics and Controlled Nuclear Fusion, Novosibirsk, paper CN–24/A1.Google Scholar
Anderson, J. E. 1963 MHD Shock Waves. MIT.Google Scholar
Ashby, D. E. T. F., Jephcott, D. F., Malein, A. & Raynor, F. A. 1965 J. Appl. Phys. 36, 29.CrossRefGoogle Scholar
Bickerton, R. J., Lenamon, L. & Murphy, R. V. W. 1971 J. Plasma Phys. 5, 177.CrossRefGoogle Scholar
Burkhardt, L. C. & Lovberg, R. C. 1962 Phys. Fluids, 5, 341.CrossRefGoogle Scholar
Chu, C. K. & Taussig, R. T. 1967 Phys. Fluids, 10, 249.CrossRefGoogle Scholar
Heiser, W. H. 1964 Phys. Fluids, 7, 143.CrossRefGoogle Scholar
Hintz, E. 1971 Proc. 4th Int. Conf. on Plasma Physics and Controlled Nuclear Fusion, Madison, paper CN-28/J-11.Google Scholar
Jukes, J. D. 1957 J. Fluid Mech. 3, 275.CrossRefGoogle Scholar
Kantrowitz, A. & Petschek, H. E. 1966 Plasma Physics in Theory and Application (ed. Kunkel, W. B.), p. 148. McGraw-Hill.Google Scholar
Keck, J. C. 1962 Phys. Fluids, 5, 630.CrossRefGoogle Scholar
Keck, J. C. 1964 Phys. Fluids (Suppl.) 7, 143.Google Scholar
Keilhacker, M., Kornherr, M., Niedermeyer, H., Steuer, K. H. & Chodura, R. 1971 Proc. 4th Int. Conf. on Plasma and Controlled Nuclear Fusion, Madison, vol. 3, p. 265.Google Scholar
Kemp, J. H. & Petschek, H. E. 1959 Phys. Fluids, 2, 499.CrossRefGoogle Scholar
Kurtmullaev, R. Kh., Masalov, V. L., Mekler, K. I. & Semenov, V. H. 1971 Soviet Phys. JETP, 33, 216.Google Scholar
Levine, L. S. 1968 Phys. Fluids, 11, 1479.CrossRefGoogle Scholar
Murphy, R. V. W. 1971 D. Phil. Thesis. University of Oxford.Google Scholar
Paul, J. W. M., Holmes, L. S., Parkinson, M. J. & Sheffield, J. 1965 Nature, Lond. 208, 133.CrossRefGoogle Scholar
Paul, J. W. M. 1970 Physics of Hot Plasmas (ed. Rye, B. J. and Taylor, J. C.), p. 302. Oliver and Boyd.CrossRefGoogle Scholar
Paul, J. W. M., Daughney, C. C., Holmes, L. S., Rumsby, P. T., Craig, A. D., Murray, E. L., Summers, D. D. R. & Beaulieu, J. 1971 Proc. 4th Int. Conf. on Plasma Physics and Controlled Nuclear Fusion, Madison, vol. 3, p. 251.Google Scholar
Peacock, N. J., Wilcock, P. D., Speer, R. J. & Morgan, P. D. 1969 Proc. 3rd Int. Conf. on Plasma Physics and Controlled Nuclear Fusion, Novosibirsk, vol. 2, p. 51.Google Scholar
Robson, A. E. & Sheffield, J. 1969 Proc. 3rd Int Conf. on Plasma Physics and Controlled Nuclear Fusion, Novosibirsk, vol. 1, p. 119.Google Scholar
Spitzer, L. 1965 Physics of Fully Ionized Gases. Interscience.Google Scholar
Stringer, T. E. 1963 Plasma Phys. 5, 89.Google Scholar
Stringer, T. E. 1964 Plasma Phys. 6, 267.Google Scholar
Taussig, R. T. 1965 Phys. Fluids, 9, 421.CrossRefGoogle Scholar
Watson-Munro, C. N., Cross, R. C. & James, B. W. 1969 Proc. 3rd Int. Conf. on Plasma Physics and Controlled Nuclear Fusion, Novosibirsk, vol. 2, p. 195.Google Scholar
Woods, L. C. 1969 Plasma Phys. 11, 25.CrossRefGoogle Scholar
Woods, L. C. 1971 J. Plasma Phys. 6, 615.CrossRefGoogle Scholar