Similarity Solution for Cylindrical Magnetohydrodynamic Blast Waves

Journal Article · Sat Dec 01 04:00:00 EST 1962 · Physics of Fluids (U.S.)

DOI:https://doi.org/10.1063/1.1706571· OSTI ID:4740466

Greifinger, C; Cole, J D

A similarity solution is obtained for the flow behind a very strong (in the hydrodynamic sense) cylindrical magnetohydrodynamic shock wave produced by the sudden release of energy along a line of infinite extent in a plasma. The plasma is assumed to be an ideal gas with infinite electrical conductivity, and to be permeated by the azimuthal magnetic field of a line current. It is shown that it is of critical importance to take into account the ambient magnetic pressure, no matter how small. It is found that, to preserve similarity, the external circuit is required to maintain a constant axial current; this result also appears in the related problem in which the ambient plasma is nonconducting. This boundary condition is shown to have consequences regarding the energy content of the system. The dependence of the shock speed on the explosive energy is determined as a function of the ambient magnetic field both for conducting and nonconducting plasma, and differences are noted. Other differences between the two cases are also discussed. (auth) Experiments on phenomena associated with the atomic recombination of nitrogen atoms are discussed. The temperature dependence of the three-body rate coefficient is found to be proportional to T^-0.6 over the temperature range of 200 to 400 deg K. The absolute photon production rate accompanying the atomic recombination in the Rayleigh afterglow is measured and found to be about one photon per 200 recombinations. The experiments rely on an electron spin resonance technique to measure the absolute atomic nitrogen density, and permit a rough determination of the dissociation energy of nitrogen. (auth)

• Research Organization: RAND Corp., Santa Monica, Calif.
• NSA Number: NSA-17-005130
• OSTI ID: 4740466
• Journal Information: Physics of Fluids (U.S.), Journal Name: Physics of Fluids (U.S.) Vol. Vol: 5; ISSN PFLDA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

BOUNDARY CONDITIONS
CIRCUITS
CURRENTS
CYLINDERS
ELECTRIC CONDUCTIVITY
ENERGY
EXPLOSIONS
FLUID FLOW
GASES
MAGNETIC FIELDS
MAGNETOHYDRODYNAMICS
MATHEMATICS
PHYSICS
PLASMA
PRESSURE
PRODUCTION
SHOCK WAVES
VELOCITY