Nuclear thermal rocket engine and nozzle therefor

Abstract

A nuclear thermal rocket engine is provided with an integrated and compact construction that facilitates vehicle size and weight reduction. The engine includes a nuclear reactor core having multiple fuel assemblies and moderator rods disposed therebetween. A reactor vessel surrounds a reflector assembly which surrounds the core and includes multiple passages formed therein for circulating coolant therethrough. The reactor vessel is surrounded by a nozzle assembly which includes a nozzle block having a plenum fluidly coupled to the outlets of the fuel assemblies and a nozzle throat region. Multiple struts extend from the reactor vessel and through the nozzle throat region to divide that region into multiple nozzle throats. Each strut includes multiple channels for circulating coolant (e.g., gaseous propellant) through the reflector assembly coolant passages and reactor core to extract heat energy from the reactor and recirculating that propellant to the fuel assemblies before being exhausted through the nozzle assembly. With this configuration, coolant can be provided to the reflector assembly without allocating valuable fuel assembly space to coolant channels. This construction also facilitates placing the reactor and nozzle in parallel with respect to the axial direction of the nozzle which further enhances the compact construction of the engine. In addition, the nozzle block, fuel assembly support and recuperator, which is provided to facilitate heat exchange from the reactor, form portions of the gamma shield, thereby reducing the weight impact of these elements on the rocket engine.

Dependencies are inferred from the claim text.