Reactors

The NSUF offers ten reactor facilities to users whose proposals are awarded access. Each of these reactors offer unique capabilities for researchers to explore basic and applied nuclear research. For a list of the technical point of contact for each facility, please click here. For more detailed information, please visit the Nuclear Energy Infrastructure Database (link). 


Idaho National Laboratory: Advanced Test Reactor

The ATR is a water-cooled, high-flux test reactor, with a unique serpentine design that allows large power variations among its flux traps. The reactor’s curved fuel arrangement places fuel closer on all sides of the flux trap positions than is possible in a rectangular grid. The reactor has nine of these high-intensity neutron flux traps and 68 additional irradiation positions inside the reactor core reflector tank, each of which can contain multiple experiments. Experiment positions vary in size from 0.5" to 5.0" in diameter and all are 48" long. The peak thermal flux is 1x1015 n/cm2-sec and fast flux is 5x1014 n/cm2-sec when operating at full power of 250 MW. There is a hydraulic shuttle irradiation system, which allows experiments to be inserted and removed during reactor operation, and pressurized water reactor (PWR) loops, which enable tests to be performed at prototypical PWR operating conditions. ATR User Guide



Idaho National Laboratory: Advanced Test Reactor Critical Facility

The ATRC is a low-power version (same size and geometry) of the higher-powered ATR core. It is operated at power levels less than 5 KW with typical operating power levels of 600 W or less. ATRC is primarily used to provide data for the design and safe operation of experiments for the ATR. ATRC is also used to supply core performance data for the restart of the ATR after periodic core internals replacement. Occasionally the ATRC is used to perform low-power irradiation of experiments. ATRC User Guide




Idaho National Laboratory: The Neutron Radiography Reactor

The Neutron Radiography (NRAD) reactor is a 250-kWth TRIGA (Training, Research, Isotopes, General Atomics) reactor that is a light water moderated, tank-type research reactor located beneath the main cell of the Hot Fuel Examination Facility (HFEF).  The NRAD facility is equipped with two neutron beamlines that route from the NRAD reactor into two separate shielded radiography stations in the lower level of HFEF, the East and North Radiography Stations (ERS and NRS, respectively). Both beamlines are designed and primarily used for neutron radiography of irradiated nuclear fuels. Both neutron beamlines have a direct line of sight to the reactor core.  

The ERS has access to items in the HFEF main cell using an object positioning elevator, while the NRS requires fuel to be moved with a cask to its object positioning elevator. Due to its ease of access to fuel specimens, the ERS is used more often for imaging used nuclear fuel than the NRS. The length-to-diameter ratio (L/D) of the ERS neutron beam is adjustable to 50, 125, or 300,  predominantly operates with an L/D of 125, which provides a thermal neutron flux of 9.5×10^6 n/cm^2-s  and a cadmium ratio of 2.7. The field of view at the image plane is 7" wide by 17" tall.  The NRAD ERS neutron radiography system is a Category-I facility, the highest quality level for a radiography facility according to the American Society for Testing and Materials (ASTM). Available imaging systems include film or computed radiography using dual-energy (thermal and epithermal) indirect transfer radiography.





Idaho National Laboratory: The Transient Reactor Test Facility

TREAT provides transient testing of nuclear fuels. It is an air-cooled, thermal spectrum test facility specifically designed to evaluate the response of reactor fuels and structural materials to accident conditions ranging from mild upsets to severe accidents. TREAT is used to study fuel melting behavior, interactions between fuel and coolant, and the potential for propagation of failure to adjacent fuel pins. TREAT has an open core design that allows for ease of experiment instrumentation and real-time imaging of fuel motion during irradiation, which also makes TREAT an ideal platform for understanding the irradiation response of materials and fuels on a fundamental level. 



Oak Ridge National Laboratory High Flux Isotope Reactor

HFIR is a versatile 85 MW research reactor offering the highest steady-state neutron flux in the western world. With a peak thermal flux of 2.5x1015 n/cm2-s and a peak fast flux of 1.1x1015 n/cm2-s, HFIR is able to quickly generate isotopes that require multiple neutron captures and perform materials irradiations that simulate lifetimes of power reactor use in a fraction of the time. HFIR typically operates 7 cycles per year, each cycle lasting between 23 and 26 days. Associated irradiation processing facilities include the Hydraulic Tube Facility, Pneumatic Tube Facilities for Neutron Activation Analysis (NAA), and Gamma Irradiation Facility. HFIR User Guide




Massachusetts Institute of Technology Reactor

The MITR is a 6 MW tank-type research reactor. It has three positions available for in-core materials, fuel and instrumentation irradiation experiments over a wide range of conditions. Water loops at pressurized water reactor/boiling water reactor (PWR/BWR) conditions, static and lead-out capsule experiments in inert gas environment at temperatures up to 850°C, custom designed high-temperature irradiation facility up to 1400°C and nuclear fuel irradiation experiments with fissile materials up to 100 gm U-235 or equivalent. A variety of instrumentation, support facilities, pneumatic tubes, beam ports, neutron activation analysis laboratory, hot cells, and non-destructive post irradiation examination facilities are also available. Fast and thermal neutron fluxes are up to 1.2e14 and 6e13 n/cm2 s at 6 MW. MIT Reactor User Guide




North Carolina State University PULSTAR Reactor

The PULSTAR reactor is a 1 MW pool-type nuclear research reactor located in NCSU’s Burlington Engineering Laboratories. The reactor, one of two PULSTAR reactors built and the only one still in operation, uses 4% enriched, pin-type fuel consisting of uranium dioxide pellets in zircaloy cladding. The fuel provides response characteristics that are very similar to commercial light water power reactors. These characteristics allow teaching experiments to measure moderator temperature and power reactivity coefficients including Doppler feedback. In 2007, the PULSTAR reactor produced the most intense low-energy positron beam with the highest positron rate of any comparable facility worldwide. PULSTAR User Guide





The Ohio State University Nuclear Reactor Laboratory

The Ohio State University Nuclear Reactor Laboratory (OSU-NRL) offers the unique capability of reactor irradiations in external large-experiment dry tubes for the OSU Research Reactor (OSURR). In the next-to-core position in which either a 6.5-in I.D. or a 9.5-in I.D. external dry tube can be located, irradiations can be performed in a neutron flux up to 1012 n/cm2/s. Among the possibilities for use are experiments involving instrumented, high-temperature irradiations of prototype instrumentation for next-generation reactors, sensors and sensor materials, and optical fibers designed for up to 1600 C. In addition to the external large-experiment dry tubes, the reactor also has two 2.5-in I.D. in-core dry tubes that also support instrumented experiments, but at ambient temperature.

OSU-NRL User Guide



Sandia National Laboratory Annular Core Research Reactor

The Sandia National Laboratory Annular Core Research Reactor (ACRR) is an epi-thermal pool-type reactor which uses cylindrical UO2-BeO fuel elements.  Sandia researchers can use the ACRR to perform sample irradiations in typical research reactor steady-state mode or in a high-power pulse mode, reaching powers as high as 30GW for a few milliseconds.  There are four main experimental cavities at the ACRR facility; central cavity, FREC-II cavity, thermal neutron beam tube (the neutron radiography facility), and the Tri-Element facility.


SNL-ACRR User Guide




Sandia National Laboratory: Pulsed Reactor Facility

The Sandia Pulsed Reactor Facility - Critical Experiments (SPRF/CX) provides a flexible, shielded location for performing critical experiments that employ different reactor core configurations and fuel types. The facility offers the following special features:

  • Facility containment within a shielded reactor room
  • The ability to modify the core configuration and reactor tank to evaluate various reactor cores for pitch, moderator characteristics, and other criteria
  • The capability for water-moderated critical experiments
  • Remote-cabling capabilities
  • A facility for hands-on criticality safety training

The SCX experiment was designed by TA-V staff to conduct a range of experiments that provide vital information for improving the efficiency of the nuclear fuel cycle in the U.S. fleet of commercial nuclear power plants. The experiments that have been conducted include BUCCX (BurnUp Credit Critical Experiment) and 7uPCX (Seven Percent Critical Experiment).