Concept of a high temperature integrated multi-modular thermal reactor

摘要

The high temperature integrated multi-modular thermal reactor is a first-of-a-kind small modular reactor that uses an enhanced conductivity BeO-UO_2 fuel with supercritical CO-2 coolant to drive turbo-machinery in a direct Brayton cycle. The core consists of several self-contained pressurized modules, each containing fuel elements in pressurized channels surrounded by a graphite moderator, and Brayton cycle turbo-machinery. Each module is subcritical by itself, and when several modules are brought into proximity of one another, a single critical core is formed. The multi-modular approach and use of BeO-UO-2 fuel with graphite moderator and supercritical CO-2 coolant leads to an inherently safe system capable of high efficiency operation. The pressure channel design and multi-modular approach eliminates engineering challenges associated with large pressure vessels, and the subcriticality of the modules ensures inherent safety during construction, transportation, and after decommissioning. A feasible configuration consisting of seven modules operating for 14.7 years at 10MWth power using 5% BeO and 5% 235U enriched fuel is presented in this paper. The results of the conceptual analysis include flux and power distributions as well as potential power shaping and reactivity coefficients were analyzed.