The Kilopower Reactor Using Stirling TechnologY (KRUSTY) Nuclear Ground Test Results and Lessons Learned

This the Kilopower reactor neutronics during steady-state, and transient operations in a space-simulated environment. This was the first space reactor test completed for fission power systems in over 50 years and marked a turning point in NASA’s nuclear program. The completed reactor power system design incorporated flight prototypic materials and full-scale components in an effort to study the reactor dynamics at full power and significantly reduce follow-on risk of a future flight demonstration. This design provided a unique opportunity for the power system to simulate several nominal and off-nominal mission scenarios that allowed the designers to verify that the reactor dynamics could tolerate many worst-case conditions regarding reactor stability and control. The dynamic changes imposed on the reactor validated the ability of the reactor to load follow the power conversion system and passively control the fuel temperature and overall system stability. With successful completion of the KRUSTY experiment, the NASA and U.S. Department of Energy (DOE) team will evaluate the lessons learned throughout the project and apply them toward a flight demonstration of a Kilopower reactor.