Fundamental Research in Explosive Magnetohydrodynamics
Final rept. 1 Oct 1974-31 Dec 1975
JONES (MALCOLM) ASSOCIATES INC CORONA DEL MAR CA
Pagination or Media Count:
The background experimental work with explosive driven MHD generators is reviewed and the major parametric factors are outlined. Previously unpublished data on the effects of the density and composition of gases originally in the channel is reviewed and it is shown that the major conduction path is through the seeded detonation products and that the role of the gas is secondary. Unpublished data on experiments with bulk seeded charges is also presented. It is shown that RDX charges surface seeded with more than 100 mg of cesium picrate produced better results than any of the bulk seeded charges tested, which contained up to 25 CsNO3. A deleterious interaction was observed when bulk seeded charges were surface seeded with cesium picrate. Analysis of this data also revealed that the anomolously high internal inductance of the explosive driven MHD generator was reduced by increasing the seed level, meaning that the seed effects both the plasma conductivity and inductance. The effect of various circulating current systems on the explosive derived plasma slug are examined. It is determined that diamagnetic surface currents coupled with a thermal ionization instability producing a T-layer can be responsible for the maintenance of the plasma conductivity in the generator. However, such a mechanism cannot be responsible for the initial conductivity observed in the vicinity of the explosive charge in the absence of a magnetic field. The physical basis for this original conductivity is uncertain.
- Plasma Physics and Magnetohydrodynamics