Recent measurements of the thermionic characteristics of duplex tungsten-niobium converters

A computer-controlled data acquisition system is being used to record and store data on the performance and thermal efficiency of a series of diodes as part of an ongoing thermionic fuel element verification program. Cesium vapor is the working gas. A cylindrical converter with a prototype liquid-cesium-graphite reservoir was constructed and its performance measured. The stored data are available for computer analysis and can be used to create complete cesium vapor families, cesium optimized curves, and power density curves in hard copy. The results of the measurements are given, and the performance of the converter is compared to that of previous converters with similar electrodes. It is shown that stable cesium vapor pressure is established in the interelectronic space using the cesium-graphite reservoir at a temperature comparable to the collector temperature