The Concept of the Combined Thermal Protection System for Leading Edges of Hypersonic Vehicles with Use of Thermionic Emission

Abstract

This work represents a conceptual stage of the project on development of technology of the combined thermal protection system for hypersonic vehicles heat-stressed surfaces with use of technology of the thermionic power cell and thermal protection system with an external emission of electrons. The relevance of this work is to develop thermal protection system technology for aircraft, enabling prolonged controlled flight at hypersonic speeds, while providing low aerodynamic resistance and relative weight, the consistency of the geometric shape of the hypersonic vehicles leading edge. The various using types of thermal protection system are compared and the necessity to develop a new type of it using the effect of thermionic emission of electrons is proved. The scheme and the possible material composition of thermionic power cell with a reversed geometry of the electrodes are given. The problem of the choice of material for emission surface of the system with external electron emission and its manufacturing technology are discussed. Using cesium intercalated graphite as one of the possible coating materials is reviewed. A sequence of forthcoming studies is formulated at the stage of transition to the design basis for the operation of thermal protection of this type.