GB1146650A - Improvements in or relating to electrodes - Google Patents

Abstract

1,146,650. Generators operating by electromagnetic interaction with fluids. INSTITUT FRANCAIS DU PETROLE, DES CARBURANTS ET LUBRIFIANTS. 1 July, 1966 [2 July, 1965; 17 Sept., 1965], No. 29622/66. Heading H2A. An electrode, for use in a MHD generator, comprises a refractory block having a region of very high electrical conductivity preferably formed by molten metal provided in the block close to the " hot " face and extending parallel to this face and connected by at least one conductor to an external circuit. The zirconia or thoria refractory block is drilled with a number of blind holes 8 which extend to within a short distance e of the hot face 5 and contain liquid metal parts 13, 14, 15. Infusible conductors 10, 11, 12 dip into the liquid metal and are connected to an external circuit at 3, the number of holes and conductors being chosen to give acceptable current carrying capacity and heat loss. To improve the conductivity adjacent the hot face the porous ceramic material in region 17 may be impregnated with a metal, e.g. copper, which is molten at the temperature of use. The conductors may alternatively consist of an infusible core surrounded by metal which is molten in use, Fig. 2 (not shown). In an alternative construction the metal may be contained in a cavity in the refractory block and may be solid or liquid in use, Figs. 3 and 4 (not shown). A graphite plate may be provided in the cavity to facilitate connection to the metal and channels may be provided in the electrode so that the hot working gas can circulate around this region of the electrode, Fig. 5 (not shown).