Track 4: Space Reactors

Paper and Podium Presentation

AuthorsTitle
2C. WangCONCEPTUAL DESIGN OF A MICRO NUCLEAR REACTOR POWER SOURCE FOR MULTI-APPLICAITON
3L. Carasik, M. Eades, V. PatelDECAY HEAT STUDIES TO REDUCE ACTIVE COOLING TIME OF A NUCLEAR THERMAL PROPULSION SYSTEM
4Z. Li, M. Lang, J. Sun, L. ShiDEVELOPMENT OF A SYSTEM ANALYSIS CODE FOR NUCLEAR THERMAL ROCKET ENGINE
5A. P. ShivprasadDEVELOPMENT OF SINTERED YTTRIUM DIHYDRIDE COMPACTS FOR NUCLEAR REACTOR MODERATOR APPLICATIONS
6S. JuddEXPERIMENTALLY VERIFYING THE EFFECTIVENESS OF FUELED CONTROL DRUMS
7M. StewartFUEL ELEMENT TO MODERATOR ELEMENT HEAT TRANSFER ANALYSIS
8B. Makenas, D. WootanHANFORD'S ROLE IN SPACE POWER
9T. G. Duffin, K. M. Benensky, S. J. Zinkle, M. W. BarnesHOT HYDROGEN TESTING AND MICROSTRUCTURAL CHARACTERIZATION OF MOLYBDENUM CERMETS FOR NUCLEAR THERMAL PROPULSION
10J. Zillinger, B. Segel, K. Benensky, D. Tucker, M. BarnesINVESTIGATION OF PRODUCTION PARAMETER EFFECTS ON SPARK PLASMA SINTERED MOLYBDENUM CERMET WAFERS FOR NUCLEAR THERMAL PROPULSION APPLICATIONS
11D. I. PostonKILOPOWER REACTORS FOR POTENTIAL SPACE EXPLORATION MISSIONS
12C. J. Romnes, D. E. Chavez, B. J. Martinez, N. M. Osterhaus, W. R. Ford, R. LenardLOW ENRICHED URANIUM NUCLEAR THERMAL ROCKET DESIGN INSPIRED BY THE SPACE NUCLEAR THERMAL PROPULSION PROJECT
13W. Carpenter, K. Benensky, M. Barnes, D. Dennis TuckerMICROSTRUCTURAL EVOLUTION OF HIGH DENSITY W-CERMETS EXPOSED TO FLOWING HYDROGEN AT TEMPERATURES EXCEEDING 2000 K
14A. Denig, M. EadesMONTE CARLO-INFORMED DECAY HEAT MODEL FOR CERMET LEU-NTP SYSTEMS
15D. SikorskiNUCLEAR THERMAL ROCKET CONTROL
16R. S. Raju, J. E. FosterOVERVIEW AND FUTURE OF OPEN CYCLE GAS-CORE NUCLEAR ROCKET
17Y. JiPARAMETRIC STUDY ON THERMAL HYDRAULICS CHARACTERISTICS OF A PARTICLE BED REACTOR FOR NUCLEAR THERMAL PROPULSION
18D. I. PostonRESULTS OF THE KRUSTY NUCLEAR SYSTEM TEST
19D. I. PostonRESULTS OF THE KRUSTY WARM CRITICAL EXPERIMENTS
20M. KrecickiSENSITIVITY STUDIES OF THE TUNGSTEN VECTOR ON THE PERFORMANCE OF A LEU NTP ENGINE
22J. Stephen Herring, S. Mackwell, C. Pestak, K. HilserSMALL MODULAR FISSION REACTORS FOR SPACE APPLICATIONS: ENABLING AN AFFORDABLE, COMMERCIALLY DEVELOPED POWER ARCHITECTURE FOR THE MOON AND BEYOND
23V. PatelSNRE EIGENVALUE UNCERTAINTY QUANTIFICATION FROM NUCLEAR DATA SOURCES
24D. Wootan, B. MakenasSPACE POWER TESTING IN THE FAST FLUX TEST FACILITY
25M. J. Eades, M. Reed, C. G. Morrison, W. Deason, S. Judd, V. Patel, P. VenneriTHE PYLON: COMMERCIAL LEU NUCLEAR FISSION POWER FOR LUNAR, MARTIAN, AND DEEP SPACE APPLICATIONS
26R. C. O\\'BrienTHE SIRIUS-1 NUCLEAR THERMAL PROPULSION FUELS TRANSIENT TEST SERIES IN THE IDAHO NATIONAL LABORATORY TREAT REACTOR
28X. LiuTHERMAL-HYDRAULIC DESIGN FEATURES OF A MICRO NUCLEAR REACTOR POWER SOURCE APPLIED FOR MULTI-PURPOSE
30M. F. Chaiken, M. A. GibsonUPDATE ON RADIATION TESTING FOR SPACE FISSION POWER SYSTEMS

Lightning Talk

AuthorsTitle
1M. HoutsA VERSATILE NUCLEAR THERMAL PROPULSION (NTP) SYSTEM
2D. BealeBERYLLIUM OXIDE AS A SOLID CORE NUCLEAR REACTOR ENGINE MODERATOR
3A. Gonzalez, W. CulbrethDECAY HEAT CAPTURE FOR ADDITIONAL NUCLEAR THERMAL ROCKET THRUST
4S. Powers, C. Powers, S. Cendro, D. Ochoa-Cota, B. KretschmerDEVELOPMENT CAMPAIGN OF AN ADDITIVELY MANUFACTURED, INDUCTIVELY HEATED MODEL OF A SOLID-CORE NUCLEAR THERMAL ROCKET ENGINE
5R. HowardDEVELOPMENT OF ROBUST AND RELIABLE EXPERIMENTS TO QUALIFY NUCLEAR THERMAL PROPULSION ENGINE FUELS AND COMPONENTS
7A. J. Rau, W. J. WaltersFISSION MATRIX NEUTRONICS CALCULATIONS WITH TEMPERATURE FEEDBACK IN A NUCLEAR THERMAL PROPULSION CORE
8P. R. Rubiolo, M. Tano Retamales, V. Ghetta, N. Capellan, J. Giraud, J. Blanco, S. DavidMOLTEN SALT REACTORS FOR NUCLEAR ELECTRIC PROPULSION
9H. Honglei, X. Jiachun, H. GuPERFORMANCE ANALYSIS OF NUCLEAR THERMAL PROPULSION REACTOR USING DRIVER FUEL ELEMENT
10K. BenenskyRECENT FY18/FY19 NTP MATERIALS DEVELOPMENT ACTIVITIES AT NASA MARSHALL SPACE FLIGHT CENTER
11M. EadesVERSATILE NTP CORE DESIGN
12H. Longmire, J. Henkel, P. Hoppe, A. MooreY-12 FABRICATION OF KRUSTY ALLOY COMPONENTS

Paper and Podium Presentation

CONCEPTUAL DESIGN OF A MICRO NUCLEAR REACTOR POWER SOURCE FOR MULTI-APPLICAITON

C. Wang chlwang@mail.xjtu.edu.cn
  Micro HPR power source is featured with lower noise level, higher power output, longer lifetime than conventional power sources. It could be applied for the energy system of space or undersea vehicles. The HPR power source is considered as an ideal candidate for the space and underwater reactor concept. In this paper, a 120kWe lithium HPR power source applied for multiple use is neutronics designed. Uranium nitride fuel with 70% enrichment and lithium heat pipe are adopted in the reactor core. Tungsten and water are used as shields on both sides of the core. The reactivity is controlled by 6 control drums with B4C neutron absorbers. Monte Carlo code MCNP is used to obtain kinetics parameters, the power distribution, shield analysis, reactivity coefficient and core criticality safety. A code MCORE coupling MCNP and ORIGEN is used to analysis the fuel depletion characteristics of the designed reactor core. A 14-year once-through fuel cycle is adopted according to optimization analysis. Overall, the designed core parameters preliminary satisfy the safety requirements and the rector is neutronics safe. This work provides reference to the design and application of the micro nuclear power source.
Download Paper

DECAY HEAT STUDIES TO REDUCE ACTIVE COOLING TIME OF A NUCLEAR THERMAL PROPULSION SYSTEM

L. Carasik, M. Eades, V. Patel l.carasik@usnc.com
Decay heating occurs within an Nuclear Thermal Propulsion (NTP) system after reactor shutdown due to fission products decaying and producing heat within the reactor. The decay heat is large enough during this period to cause the NTP system components to heat up past their temperature limits without sufficient cooling. If the temperature limits are surpassed, the NTP system could be damaged including the reactor core components. This is mitigated by the usage of both active and passive cooling stages after the NTP system shuts down. The active stage requires the expenditure of reactor coolant (also the propellant of the NTP) to cool the system. This coolant/propellant is contained within the NTP system and the more coolant/propellant needed translates to the higher mass and cost requirement of the NTP system. This motivates an effort to reduce the active cooling stage that in turn reduces system mass and costs. In this work, two design parameters are investigated for potential reduction of the active cooling stage length. These investigations are done by modeling a simplified NTP system using TRICORDER and it was found that the active cooling stage can be reduced by using high emissivity radiator coatings and the addition of radiator fins.
Download Paper

DEVELOPMENT OF A SYSTEM ANALYSIS CODE FOR NUCLEAR THERMAL ROCKET ENGINE

Z. Li, M. Lang, J. Sun, L. Shi lizeguang@mail.tsinghua.edu.cn
A new system analysis code for nuclear thermal rocket engine (NTRE) is developed, which can perform the whole NTRE system simulation. In this paper, the models of hydrogen physical property and system balance calculation used in the analysis code are briefly introduced to show the basic idea of the code. Then system simulations have been done on the three cycle schemes for 100 kN thrust, and the detailed working parameters of each cycle has been obtained. On the basis of these results, the comparison is done among the three cycles.
Download Paper

DEVELOPMENT OF SINTERED YTTRIUM DIHYDRIDE COMPACTS FOR NUCLEAR REACTOR MODERATOR APPLICATIONS

A. P. Shivprasad aps@lanl.gov
High-density compacts of yttrium dihydride were synthesized using powder metallurgy and exhibited densities greater than 90% of the theoretical density. Compacts were then examined for phase purity using X-ray diffraction and elastic properties using resonant ultrasound spectroscopy. Results showed that sintered material was made up of approximately 1% yttrium trihydride and the rest yttrium dihydride. Youngs, bulk, and shear moduli were all lower than reported in literature and were attributed to internal porosity. Modulus values were clearly observed to vary as functions of density, while Poissons ratio was calculated as 0.221 0.003 and was independent of density. This work represents a novel achievement in demonstrating the feasibility of powder processing techniques to yield high-density yttrium dihydride compacts.
Download Paper

EXPERIMENTALLY VERIFYING THE EFFECTIVENESS OF FUELED CONTROL DRUMS

S. Judd s.judd@usnc.com
Water submersion criticality is a known problem in all current LEU Nuclear Thermal Propulsion core designs. This paper concerns a new control drum design that has the required control authority to shutdown cores even when submerged in water. It then describes the design, process, and results of a low-cost experiment used to test the feasibility and functionality of this new design.
Download Paper

FUEL ELEMENT TO MODERATOR ELEMENT HEAT TRANSFER ANALYSIS

M. Stewart Mark.E.Stewart@nasa.gov
This paper concerns an issue in Nuclear Thermal Propulsion (NTP) reactor design, namely, the heat flow between Fuel Elements (FE) and Moderator Elements (ME) in a reactor. This question is important as this heat flow is used to drive the propellant turbopumps, and must be properly matched for successful operation of relevant rocket reactors. The current NASA GCD NTP design requires insight into this issue. This heat flow is more complex than simple conduction. This paper aims to quantify the relevant effects through 1-D heat equation analysis and ANSYS 2-D thermal simulations.
Download Paper

HANFORD'S ROLE IN SPACE POWER

B. Makenas, D. Wootan David.wootan@pnnl.gov
Hanford\'s role in early space reactor development and testing ranged from thermo-electric and thermionic power systems, SP-100 test reactor fuels testing, the design and fabrication of the SP-100 ground engineering system test, thermal propulsion testing for the Multi-MW reactor, and the proposed Jupiter Icy Moons Orbiter (JIMO) reactor.
Download Paper

HOT HYDROGEN TESTING AND MICROSTRUCTURAL CHARACTERIZATION OF MOLYBDENUM CERMETS FOR NUCLEAR THERMAL PROPULSION

T. G. Duffin, K. M. Benensky, S. J. Zinkle, M. W. Barnes tduffin2@vols.utk.edu
Nuclear thermal propulsion is capable of high specific impulse as well as high thrust and is the leading candidate propulsion technology for a crewed Mars mission. In this study, molybdenum ceramic metallic fuels were produced via spark plasma sintering and tested at 2000 K, 2250 K and 2500 K in flowing hydrogen in both thermal cycling and steady-state conditions. Tested samples were evaluated for mass loss and their microstructure was characterized. Mass loss was greater for thermally cycled samples than for those at steady-state and increased with both temperature and ceramic volume loading. Intense damage was observed in the ceramic particles in specific regions for the 2000 K tests that had higher frequency under thermal cycling.
Download Paper

INVESTIGATION OF PRODUCTION PARAMETER EFFECTS ON SPARK PLASMA SINTERED MOLYBDENUM CERMET WAFERS FOR NUCLEAR THERMAL PROPULSION APPLICATIONS

J. Zillinger, B. Segel, K. Benensky, D. Tucker, M. Barnes zill0470@vandals.uidaho.edu | rns59@case.edu
This study focused on nuclear fuel fabrication using powder blending and spark plasma sintering (SPS) of Mo-ZrO2 surrogate ceramic-metal (cermet) fuels. The study consisted of two co-projects: a powder blending/distribution study and an SPS parameter optimization study. The powder blending study focused on optimization of the powder processing parameters in order to fabricate high density cermets with uniformly distributed dispersed ceramic microstructures. The SPS parameter optimization study focused on the impact of sintering parameters (temperature, dwell time, and pressure) on the microstructural properties of a cermet (density/porosity, grain structure, and hardness). In the powder blending and distribution study, addition of 0.1 wt% and 0.5 wt% binder resulted in complete coverage and even distribution of large, spherical ZrO2 particles with Mo powder for batches of 50 vol% and 60 vol% ceramic loading respectively. When optimizing SPS parameters, fuel density (decreased porosity) was directly related to increase in sintering temperature, pressure, and time. Grain diameter and material hardness were observed to increase with temperature and pressure as well, indicating grain growth during the sintering process. Optimal sintering parameters suggested from this study, for Mo-ZrO2 cermets with 60 vol% ceramic loading, were found to be at a temperature of 1400C, at 50 MPa uniaxial pressure, for at least 5 minutes dwell time.
Download Paper

KILOPOWER REACTORS FOR POTENTIAL SPACE EXPLORATION MISSIONS

D. I. Poston poston@lanl.gov
Fission systems can expand our capability to explore space by orders of magnitude. This paper presents variations of the Kilopower concept, which could provide robust, long-lived power from 1 to 10 kWe for space exploration missions. The small, simple reactor design uses existing technology and lends itself to quick and affordable development. The simplicity in design, operation and development led to the success of the Demonstration Using Flattop Fissions (DUFF) and Kilowatt Reactor Using Stirling TechnologY (KRUSTY) tests. Conceptual designs and masses are presented for 1-kWe space science mission, 10-kWe NEP missions, a 1-kWe lunar demo mission and a 10-kWe Mars ISRU demo mission.
Download Paper

LOW ENRICHED URANIUM NUCLEAR THERMAL ROCKET DESIGN INSPIRED BY THE SPACE NUCLEAR THERMAL PROPULSION PROJECT

C. J. Romnes, D. E. Chavez, B. J. Martinez, N. M. Osterhaus, W. R. Ford, R. Lenard gemini.carly@gmail.com
The development of a low enriched, nuclear thermal rocket (NTR) has become a necessity for more effective deep space travel. An NTR provides a significantly higher specific impulse (I sp ) than chemical rockets. Starting in the 1960s the United States began the Nuclear Engine for Rocket Vehicle Applications (NERVA) program. The overall design of the NTR described in this paper, INsTAR, incorporates many elements from the NERVA prototypes. While many NERVA engines incorporated a high enriched uranium fuel, the low enriched uranium fuel concepts have proven to be feasible. The overall design objective was to develop a full core design for an NTR that addresses the problems found in the Space Nuclear Thermal Propulsion Project core and improves upon the I sp and thrust to weight ratio observed during the project. The core design is characterized with respect to neutronics, thermal hydraulics, and propulsive performance. A critical component of the design was the study of materials utilized in the core and their compatibilities at high operating temperatures.
Download Paper

MICROSTRUCTURAL EVOLUTION OF HIGH DENSITY W-CERMETS EXPOSED TO FLOWING HYDROGEN AT TEMPERATURES EXCEEDING 2000 K

W. Carpenter, K. Benensky, M. Barnes, D. Dennis Tucker william.carpenter@mines.sdsmt.edu
Nuclear thermal propulsion (NTP) shows promising potential for crewed space exploration by enabling high specific impulse and thrust. The development of NTP systems presents unique fuel material challenges due to requirements for high operating temperatures, exceeding 2500 K, and chemical compatibility with a hydrogen propellant (coolant) during operation. NASA has been investigating ceramic-metal (cermet) fuels due to their high temperature capability and hydrogen compatibility of the refractory metal matrix. For this study, subscale tungsten (W) cermet specimens, with 60 vol% zirconia surrogate (ZrO2), were consolidated via spark plasma sintering (SPS). Sintered samples were tested at 2000C for 60 minutes and 2500?C for 5 minutes in flowing H2. After testing, as produced and tested specimens were cross sectioned for microstructural examination using optical microscopy, scanning electron microscopy, and microhardness in order to understand the stability of the bulk cermet microstructure under the different conditions. While the specimens retained structural integrity throughout testing with minimal mass loss, the microstructural investigation revealed hydrogen attack and migration of ZrO2 particles. Overall, the W matrix showed minimal grain growth and embrittlement as a result of testing.
Download Paper

MONTE CARLO-INFORMED DECAY HEAT MODEL FOR CERMET LEU-NTP SYSTEMS

A. Denig, M. Eades andrewdenig@hotmail.com
Two methodologies for performing decay heat analysis with Monte Carlo simulations were developed and implemented on a representative nuclear thermal rocket (NTR) design. This paper presents the underlying theory, discusses the methodology, and states the key results. This work investigated the importance of utilizing a time-dependent Q-value for fission in NTRs due to its short burn time. Two approaches for deriving the Q-value were taken: one based on deconvolving the fission rate from the power to yield the rate of fission energy deposition, and the other based on the convergence of the fission product decay power during a long burn. The fission product decay power method produces results closer to theoretical values, as it captures more of the underlying physics occurring during burnup such as fission product transmutation. The calculated Q-values were employed to derive decay power profiles which were compared to the Emrich1 model. According to these new models, the Emrich model underestimates the amount of hydrogen required for decay heat cooling by as much as 23.3%.
Download Paper

NUCLEAR THERMAL ROCKET CONTROL

D. Sikorski dsikorsk@vols.utk.edu
This paper presents the historical methods of control of nuclear thermal rockets (NTR), with a focus on the state of the technology, with the most recent NTR control experience being the United States Rover program. Gaps in control technology are identified and next steps in developing controls for nuclear thermal rockets are proposed.
Download Paper

OVERVIEW AND FUTURE OF OPEN CYCLE GAS-CORE NUCLEAR ROCKET

R. S. Raju, J. E. Foster ritzsr@umich.edu
Human exploration of entire solar system can be enabled if the gas core nuclear rocket concept is made feasible. The Gas-Core Nuclear Rocket has the potential to greatly reduce the trip time for a given mission as compared to chemical or electric propulsion systems. Operating at high temperature (104 105 K), the Gas-Core Nuclear Rocket achieve specific impulse (approaching 5000 s) and high thrust, essentially eclipsing conventional solid core nuclear thermal rockets. Challenges to the realization of this technology include 1) stably confining fissioning plasma, 2) preventing plasma erosion due to mixing and subsequent entrainment with hydrogen fuel, 3) optimizing heat transfer from the uranium plasma to the hydrogen fuel, and 4) protecting the nozzle from the high-temperature exhaust. In this review, past gas core nuclear technology development is surveyed along with a discussion of the current status of the technology.
Download Paper

PARAMETRIC STUDY ON THERMAL HYDRAULICS CHARACTERISTICS OF A PARTICLE BED REACTOR FOR NUCLEAR THERMAL PROPULSION

Y. Ji jiyu1994joe11@163.com
Nuclear Thermal Propulsion (NTP) is regarded as a promising technology and selected as the leading candidate for the human exploration to Mars, as suggested in Design Reference Architecture 5.0 (DRA 5.0). For a long time, many novel NTP systems have been proposed, designed and tested, among which Nuclear Engine for Rocket Vehicle Application (NERVA) is the most famous one. In the NERVA program, enormous technologies were developed and some records were accomplished. Based on these achievements, a more excellent, compact and lightweight design, i.e., particle bed reactor (PBR) was proposed in the 1980s. In this paper, the thermal hydraulics characteristics of a proposed PBR are investigated. By assuming the characteristics are indifferent along the circumference, a two-dimensional steady-state analysis concerning the turbulent flows in PBR is performed using Computational Fluid Dynamics (CFD) tool. In addition, some further work investigates the effect of various aspects including flow direction, mass flow rate and the height of the nuclear reactor core on the internal flow and heat transfer processes within the reactor core. These findings may provide technical support for the subsequent design of PBR.
Download Paper

RESULTS OF THE KRUSTY NUCLEAR SYSTEM TEST

D. I. Poston poston@lanl.gov
The Kilowatt Reactor Using Stirling TechnologY (KRUSTY) was a prototypic nuclear-powered test of a 5-kWt Kilopower space reactor. This paper presents results from the KRUSTY nuclear system test, which operated the reactor power system at various temperatures and power levels for 28 consecutive hours. The testing showed that the system operated as expected, and that the reactor is highly tolerant of possible failure conditions and transients. The key feature demonstrated was the ability of the reactor to load-follow the demand of the power conversion system. The thermal power of the test ranged from 1.5 to 5.0 kWt, with a fuel temperature up to 880 C. Each 80-We-rated Stirling engine produced ~90 We at a component efficiency of ~35% and an overall system efficiency of ~25%.
Download Paper

RESULTS OF THE KRUSTY WARM CRITICAL EXPERIMENTS

D. I. Poston poston@lanl.gov
The Kilowatt Reactor Using Stirling TechnologY (KRUSTY) was a prototypic nuclear-powered test of a 5-kWt Kilopower space reactor. This paper presents results from the KRUSTY critical experiments, which were completed prior to the final system test. The first set of criticals were cold or zero-power criticals; i.e. the core was not heated by fission power. These were followed by three warm criticals, where fission power heated the core to 200, 300 and 450 C respectively. These criticals provided the data and confidence required to proceed with the KRUSTY nuclear system test. The criticals also provided valuable data for the benchmarking of codes applicable to all nuclear systems. Overall, the results of the KRUSTY criticals, cold and warm, matched extremely well with the pre-test predictions
Download Paper

SENSITIVITY STUDIES OF THE TUNGSTEN VECTOR ON THE PERFORMANCE OF A LEU NTP ENGINE

M. Krecicki mkrecicki@gatech.edu
This paper explores the sensitivity of the criticality to the tungsten vector for a nuclear thermal propulsion (NTP) core, utilizing low enriched uranium (LEU) fuel. Tungsten ceramic metal composite (cermet) fuel is required due to the extremely high temperatures achieved in the core. However, tungsten has a non-negligible thermal neutron absorption cross section. This requires the tungsten to be enriched to contain mostly 184W to maintain a critical configuration. The results of this study show that the core favors a harder spectrum, as expected, to reduce the parasitic absorption in tungsten. In addition, inaccurate tungsten vector definition (or relatively high manufacturing tolerances) can have a detrimental effect on the prediction of criticality, i.e., above 1,000 pcms.
Download Paper

SMALL MODULAR FISSION REACTORS FOR SPACE APPLICATIONS: ENABLING AN AFFORDABLE, COMMERCIALLY DEVELOPED POWER ARCHITECTURE FOR THE MOON AND BEYOND

J. Stephen Herring, S. Mackwell, C. Pestak, K. Hilser jherring@usra.edu
More capable robotic exploration, ISRU, and sustained human presence will require electrical power in the 40 kW to 150 kW range that is continuously available throughout the entire day/night cycles of the planetary body being explored. In the case of the Moon, a power plant capable of meeting this need would form the basis for establishing commercial electrical utility services on the lunar surface. Such services will jump-start the exploration, resource mapping, commercial exploitation, and colonization of the Moon by a broad mix of public and private users that include space agencies, industries, adventurers, and entrepreneurs. To address the challenges and opportunities of establishing in-space commercial electrical utilities, Universities Space Research Association (USRA) recently began an internal research and development (IRAD) project to perform a concept study of a new small modular fission reactor (SMFR) targeted for use on the Moon.
Download Paper

SNRE EIGENVALUE UNCERTAINTY QUANTIFICATION FROM NUCLEAR DATA SOURCES

V. Patel v.patel@usnc.com
Nuclear thermal propulsion designs include large margins for manufacturing, thermal, and neutronic uncertainties. In the past these uncertainties could be better understood through rapid design and experimental measurements. With shifts to more effort on computational designs and larger computing power available, uncertainties can be quantified using computational means. New nuclear thermal propulsion designs use monte-carlo analysis where well established deterministic uncertainty quantification techniques are not valid. This paper describes a total monte-carlo method that can be applied to determine sensitivities and uncertainties to neutron multiplication factors, neutron spectrum, and burnup from many sources including geometrical, material, and nuclear data. Focus is placed on comparing the Small Nuclear Rocket Engine eigenvalue uncertainty found to the iterated fission probability method.
Download Paper

SPACE POWER TESTING IN THE FAST FLUX TEST FACILITY

D. Wootan, B. Makenas David.wootan@pnnl.gov
Westinghouse Hanford Company (WHC) was deeply involved in the development of a 100-kilowatt electric reactor for space, called SP-100, funded jointly by the National Aeronautics and Space Administration, the Department of Energy, and the Department of Defense, specifically the Strategic Defense Initiative Office. The SP-100 program was initiated in 1983 for the development of a compact nuclear reactor capable of producing electrical power in the range of 10 to 1000 kilowatt electric. This was a national program with contributions by the Jet Propulsion Laboratory, Los Alamos National Laboratory, Oak Ridge National Laboratory, the General Electric Company, Westinghouse Hanford Company, and a number of industrial suppliers. The mission of the program was to develop technology to support construction of a flight prototype in the mid-1990\'s. .
Download Paper

THE PYLON: COMMERCIAL LEU NUCLEAR FISSION POWER FOR LUNAR, MARTIAN, AND DEEP SPACE APPLICATIONS

M. J. Eades, M. Reed, C. G. Morrison, W. Deason, S. Judd, V. Patel, P. Venneri m.eades@usnc.com
USNC-Space is a wholly U.S. owned and operated company that was spun out of USNC to commercialize nuclear technology for space applications. USNC is a commercial company developing a terrestrial gas-cooled micro-modular reactor (MMR) for off-grid and rugged locations on Earth. The Pylon is a low-enriched uranium (LEU) fission reactor system utilizing the core technology of the MMR to provide electrical power and heat in locations such as the Moon, Mars, and open space. The reactor was designed to provides 1 MWth for a period of 10 years at temperatures of 1150 K. A direct-cycle Brayton power conversion system was baselined for power conversion. For Lunar and space applications a radiator was used for heat rejection, while a convective design was used for the Mars concept. The Pylon was designed to have a mass under 5,000 kg and to be able to provide hundreds of kWth for ISRU operations at heat rejection temperatures and high-quality process heat at temperatures as high as 1150 K.
Download Paper

THE SIRIUS-1 NUCLEAR THERMAL PROPULSION FUELS TRANSIENT TEST SERIES IN THE IDAHO NATIONAL LABORATORY TREAT REACTOR

R. C. O\\'Brien Robert.Obrien@inl.gov
Nuclear Thermal Propulsion (NTP) fuels and component materials are subjected to extreme temperature transients through nuclear heating to NTP system from space cold to operational temperatures. Methodology for transient testing conceptual NTP fuels is presented in addition to the capsule design for static testing under the SIRIUS-1 series at the Idaho National Laboratory Transient Reactor Test (TREAT) reactor.
Download Paper

THERMAL-HYDRAULIC DESIGN FEATURES OF A MICRO NUCLEAR REACTOR POWER SOURCE APPLIED FOR MULTI-PURPOSE

X. Liu lx1181605510@163.com
Micro heat pipe cooled reactor power source (HRP) could be applied for space or underwater vehicles and it meets the future demands of them, safer structure, longer operating time, fewer mechanical moving parts than conventional power devices. In this paper, a 50kWe potassium heat pipe cooled reactor power source system is proposed. The reactor core is featured with Uranium nitride fuel and potassium heat pipes. Tungsten and water are used as shields and the reactivity is controlled by control drums. The thermoelectric generator (TEG) consists of thermoelectric conversion units and water cooler. The thermoelectric conversion units convert thermal energy to electric energy through the high-performance thermoelectric material. A code applied for designing and analyzing the rector power system is developed. It consists of multi-channel rector core model, heat pipe model using thermal resistance network, thermoelectric conversion and thermal conductivity model. Then tthe steady-state calculations are also conducted. It is concluded that the preliminary design of HPR design is reasonable and reliable. The designed residual heat removal system has sufficient safety margin to release the decay heat of the reactor. This work provides reference to the design of heat pipe cooled micro nuclear power source.
Download Paper

UPDATE ON RADIATION TESTING FOR SPACE FISSION POWER SYSTEMS

M. F. Chaiken, M. A. Gibson max.f.chaiken@nasa.gov
Radiation effects on materials and electronics is a major topic that needs to be addressed for the advancement of Kilopower fission reactor power systems. The Kilopower project team has taken steps towards developing a standardized radiation environment qualification test plan for components and materials. Candidate nuclear reactor facilities for both low fluence electronics and high fluence materials irradiations have been identified and approached. Collaborations are being pursued with both NASA and external experts to ensure that the results of the qualification testing are appropriate and relevant to nuclear fission power flight systems.
Download Paper

Lightning Talk

A VERSATILE NUCLEAR THERMAL PROPULSION (NTP) SYSTEM

M. Houts michael.houts@nasa.gov
For full papers, please enter your abstract here (250 words or less). For lightning talks, ignore this field.
Download Paper

BERYLLIUM OXIDE AS A SOLID CORE NUCLEAR REACTOR ENGINE MODERATOR

D. Beale danimarie24@outlook.com
For full papers, please enter your abstract here (250 words or less). For lightning talks, ignore this field.
Download Paper

DECAY HEAT CAPTURE FOR ADDITIONAL NUCLEAR THERMAL ROCKET THRUST

A. Gonzalez, W. Culbreth aimeegonz53@yahoo.com
For full papers, please enter your abstract here (250 words or less). For lightning talks, ignore this field.
Download Paper

DEVELOPMENT CAMPAIGN OF AN ADDITIVELY MANUFACTURED, INDUCTIVELY HEATED MODEL OF A SOLID-CORE NUCLEAR THERMAL ROCKET ENGINE

S. Powers, C. Powers, S. Cendro, D. Ochoa-Cota, B. Kretschmer scpowers@usc.edu
For full papers, please enter your abstract here (250 words or less). For lightning talks, ignore this field.
Download Paper

DEVELOPMENT OF ROBUST AND RELIABLE EXPERIMENTS TO QUALIFY NUCLEAR THERMAL PROPULSION ENGINE FUELS AND COMPONENTS

R. Howard howardrh@ornl.gov
For full papers, please enter your abstract here (250 words or less). For lightning talks, ignore this field.
Download Paper

FISSION MATRIX NEUTRONICS CALCULATIONS WITH TEMPERATURE FEEDBACK IN A NUCLEAR THERMAL PROPULSION CORE

A. J. Rau, W. J. Walters wjw24@psu.edu
n/a
Download Paper

MOLTEN SALT REACTORS FOR NUCLEAR ELECTRIC PROPULSION

P. R. Rubiolo, M. Tano Retamales, V. Ghetta, N. Capellan, J. Giraud, J. Blanco, S. David pablo.rubiolo@lpsc.in2p3.fr
For full papers, please enter your abstract here (250 words or less). For lightning talks, ignore this field.
Download Paper

PERFORMANCE ANALYSIS OF NUCLEAR THERMAL PROPULSION REACTOR USING DRIVER FUEL ELEMENT

H. Honglei, X. Jiachun, H. Gu huohl09@163.com
For full papers, please enter your abstract here (250 words or less). For lightning talks, ignore this field.
Download Paper

RECENT FY18/FY19 NTP MATERIALS DEVELOPMENT ACTIVITIES AT NASA MARSHALL SPACE FLIGHT CENTER

K. Benensky kelsabenensky@gmail.com
For full papers, please enter your abstract here (250 words or less). For lightning talks, ignore this field.
Download Paper

VERSATILE NTP CORE DESIGN

M. Eades m.eades@usnc.com
For full papers, please enter your abstract here (250 words or less). For lightning talks, ignore this field.
Download Paper

Y-12 FABRICATION OF KRUSTY ALLOY COMPONENTS

H. Longmire, J. Henkel, P. Hoppe, A. Moore hollie.longmire@cns.doe.gov
For full papers, please enter your abstract here (250 words or less). For lightning talks, ignore this field.
Download Paper