WALL STRUCTURES OF MAGNETOHYDRODYNAMIC CONVERSION DUCTS AND METHOD OF FABRICATION OF SAID STRUCTURES

摘要

An MHD generator duct has thin internally projecting segments of refractory metal forming the electrodes assembled in alternate relationships with segments of refractory material. The refractory metal electrodes E are formed of a thin projection b brazed into a foot portion a which is embedded in grooves 3 in the ceramic refractory material and are constructed such that the ratio of the projection h to the distance d between electrodes is 1 : 5. The segments are between 20 and 50 microns thick. In forming a cylindrical duct, tubes of refractory material are cut lengthwise along a chord and the two tubes having the largest cross-section are assembled together with an interfitting scarf joint to provide a cylindrical tube, Figs. 6 and 7 (not shown). After the electrodes have been fitted the complete assembly is enclosed in a concentric refractory tube to reduce leakage. In a modification the thin annular electrodes are assembled between rings of refractory material and the assembly enclosed in a support tube of carbon silicide. After sintering at 1600 C. to bond the metal segments to the ceramic the assembly is enclosed in a concentric refractory tube.