Marc A. Gibson

Bio: Marc A. Gibson is an academic researcher from Glenn Research Center. The author has contributed to research in topics: Stirling engine & Heat pipe. The author has an hindex of 9, co-authored 34 publications receiving 254 citations.

NASA's Kilopower reactor development and the path to higher power missions

Abstract: The development of NASA's Kilopower fission reactor is taking large strides toward flight development with several successful tests completed during its technology demonstration trials. The Kilopower reactors are designed to provide 1–10 kW of electrical power to a spacecraft or lander, which could be used for additional science instruments, the ability to power electric propulsion systems, or support human exploration on another planet. Power rich nuclear missions have been excluded from NASA mission proposals because of the lack of radioisotope fuel and the absence of a flight qualified fission system. NASA has partnered with the Department of Energy's National Nuclear Security Administration to develop the Kilopower reactor using existing facilities and infrastructure and determine if the reactor design is suitable for flight development. The three-year Kilopower project started in 2015 with a challenging goal of building and testing a full-scale flight-prototypic nuclear reactor by the end of 2017. Initially, the power system will undergo several non-nuclear tests using an electrical heat source and a depleted uranium core to verify the complete non-nuclear system design prior to any nuclear testing. After successful completion of the depleted uranium test, the system will be shipped to the Nevada National Security Site where it will be fueled with the highly enriched uranium core and re-tested using the nuclear heat source. At completion of the project, NASA will have a significant sum of experimental data with a flight-prototypic fission power system, greatly reducing the technical and programmatic risks associated with further flight development. To compliment the hardware rich development progress, a review of several higher power mission studies are included to emphasize the impact of having a flight qualified fission reactor. The studies cover several science missions that offer nuclear electric propulsion with the reactor supplying power to the spacecraft's propulsion system and the science instruments, enabling a new class of outer planet missions. A solar versus nuclear trade for Mars surface power is also reviewed to compare the advantages of each system in support of ascent vehicle propellant production and human expeditions. These mission studies offer insight into some of the benefits that fission power has to offer but still lacks a wider audience of influence. For example, mission directorates won't include a fission power system in their solicitations until it's flight qualified, and scientists won't propose new missions that require more power than what's currently proven and available. An attempt to break this chicken and egg effect has been ongoing with the Kilopower project with the goal of advancing the technology to a level that encourages a flight development program and allows scientists to propose new ideas for higher power missions.

Kilopower Project: The KRUSTY Fission Power Experiment and Potential Missions

Abstract: The Kilopower Project was initiated by NASA’s Space Technology Mission Directorate/Game Changing Development Program in fiscal year 2015 to demonstrate subsystem-level technology readiness of small...

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

Abstract: The Kilopower nuclear ground testing nicknamed KRUSTY (Kilopower Reactor Using Stirling TechnologY) was completed at the Nevada Nuclear Security Site (NNSS) on March 21, 2018. This full scale nuclear demonstration verified the Kilopower reactor neutronics during startup, 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 expected and unexpected 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/DOE team will evaluate the lessons learned throughout the project and apply them towards a flight demonstration of a Kilopower reactor.

KRUSTY Reactor Design

Abstract: The Kilowatt Reactor Using Stirling TechnologY (KRUSTY) was a reactor design, development, and test program to demonstrate the nuclear operation of a Kilopower reactor. Kilopower systems are intend...

Results of the KRUSTY Nuclear System Test

Abstract: The Kilowatt Reactor Using Stirling TechnologY (KRUSTY) was a prototypic nuclear-powered test of a 5-kW(thermal) Kilopower space reactor. This paper presents results from the KRUSTY nuclear system ...

Electric propulsion for satellites and spacecraft: established technologies and novel approaches

Abstract: This contribution presents a short review of electric propulsion (EP) technologies for satellites and spacecraft. Electric thrusters, also termed ion or plasma thrusters, deliver a low thrust level compared to their chemical counterparts, but they offer significant advantages for in-space propulsion as energy is uncoupled to the propellant, therefore allowing for large energy densities. Although the development of EP goes back to the 1960s, the technology potential has just begun to be fully exploited because of the increase in the available power aboard spacecraft, as demonstrated by the very recent appearance of all-electric communication satellites. This article first describes the fundamentals of EP: momentum conservation and the ideal rocket equation, specific impulse and thrust, figures of merit and a comparison with chemical propulsion. Subsequently, the influence of the power source type and characteristics on the mission profile is discussed. Plasma thrusters are classically grouped into three categories according to the thrust generation process: electrothermal, electrostatic and electromagnetic devices. The three groups, along with the associated plasma discharge and energy transfer mechanisms, are presented via a discussion of long-standing technologies like arcjet thrusters, magnetoplasmadynamic thrusters, pulsed plasma thrusters and ion engines, as well as Hall thrusters and variants. More advanced concepts and new approaches for performance improvement are discussed afterwards: magnetic shielding and wall-less configurations, negative ion thrusters and plasma acceleration with a magnetic nozzle. Finally, various alternative propellant options are analyzed and possible research paths for the near future are examined.

NASA's Kilopower reactor development and the path to higher power missions

Abstract: The development of NASA's Kilopower fission reactor is taking large strides toward flight development with several successful tests completed during its technology demonstration trials. The Kilopower reactors are designed to provide 1–10 kW of electrical power to a spacecraft or lander, which could be used for additional science instruments, the ability to power electric propulsion systems, or support human exploration on another planet. Power rich nuclear missions have been excluded from NASA mission proposals because of the lack of radioisotope fuel and the absence of a flight qualified fission system. NASA has partnered with the Department of Energy's National Nuclear Security Administration to develop the Kilopower reactor using existing facilities and infrastructure and determine if the reactor design is suitable for flight development. The three-year Kilopower project started in 2015 with a challenging goal of building and testing a full-scale flight-prototypic nuclear reactor by the end of 2017. Initially, the power system will undergo several non-nuclear tests using an electrical heat source and a depleted uranium core to verify the complete non-nuclear system design prior to any nuclear testing. After successful completion of the depleted uranium test, the system will be shipped to the Nevada National Security Site where it will be fueled with the highly enriched uranium core and re-tested using the nuclear heat source. At completion of the project, NASA will have a significant sum of experimental data with a flight-prototypic fission power system, greatly reducing the technical and programmatic risks associated with further flight development. To compliment the hardware rich development progress, a review of several higher power mission studies are included to emphasize the impact of having a flight qualified fission reactor. The studies cover several science missions that offer nuclear electric propulsion with the reactor supplying power to the spacecraft's propulsion system and the science instruments, enabling a new class of outer planet missions. A solar versus nuclear trade for Mars surface power is also reviewed to compare the advantages of each system in support of ascent vehicle propellant production and human expeditions. These mission studies offer insight into some of the benefits that fission power has to offer but still lacks a wider audience of influence. For example, mission directorates won't include a fission power system in their solicitations until it's flight qualified, and scientists won't propose new missions that require more power than what's currently proven and available. An attempt to break this chicken and egg effect has been ongoing with the Kilopower project with the goal of advancing the technology to a level that encourages a flight development program and allows scientists to propose new ideas for higher power missions.