DYNAMIC SIMULATION OF THE THERMAL AND ELECTRICAL BEHAVIOR OF A THERMIONIC CONVERTER COUPLED TO A SOLAR CONCENTRATOR

摘要

A mathematical simulation for the dynamic thermal and electrical behavior of a thermionic converter coupled to a solar concentrator, is presented. The thermionic device is a Cesium-filled thermionic diode operating in the ignited mode. The emitter of the device is made of polycrystalline Rhenium and the collector of the device of Molybdenum. The solar concentrator is a parabolic dish. The designed emitter and collector temperatures are 1850 K and 928 K, respectively. However, due to changes in ambient conditions, the collector efficiency varies and so does the system efficiency. This fact makes it necessary to evaluate the design of the system not just for one hour with constant conditions but also for a whole operating day. The paper presents plots for the emitter and collector thermionic device temperatures and power and voltage for a constant resistance load as a function of time.