Abstract: A reflector assembly for a molten chloride fast reactor (MCFR) includes a support structure with a substantially cylindrical base plate, a substantially cylindrical top plate, and a plurality of circumferentially spaced ribs extending between the base plate and the top plate. The support structure is configured to encapsulate a reactor core for containing nuclear fuel. The MCFR also includes a plurality of tube members disposed within the support structure and extending axially between the top plate and the bottom plate. The plurality of tube members are configured to hold at least one reflector material to reflect fission born neutrons back to a center of the reactor core.

Abstract: A modular nuclear reactor system includes a lift-out, replaceable nuclear reactor core configured for replacement as a singular unit during a single lift-out event, such as rather than lifting and replacing individual fuel assemblies and/or fuel elements. The system includes a reactor vessel and a power generation system configured to convert thermal energy in a high temperature working fluid received from the reactor vessel into electrical energy. The reactor vessel includes: a vessel inlet and an adjacent vessel outlet arranged near a bottom on the vessel; a vessel receptacle configured to receive a unified core assembly; locating datums in the base of the vessel receptacle and configured to constrain a core assembly in multiple degrees of freedom; and an interstitial zone surrounding the vessel receptacle and housing a set of control or moderating drums.

Abstract: A moving light tester includes plural sensors, each of which can test a function of the moving light. A conveyor can move the light between the sensors. Once tested, information about the test is used to characterize the light, to determine if it needs repair, or can be re rented. The information can also be used to create inventory lists, and bills for damage. The testing can include automated testing for gobos, colors, noise, heating and movement, or other tests.

Abstract: A method of and a system for evaluating constraint functions for improving nuclear reactor performance involve generating an operational solution for a nuclear reactor using a constraint to account for a problem with the operation of the nuclear reactor. The problem is based at least in part on channel deformation criteria.

Abstract: A fast reactor including a reactivity control assembly including a reactor shutdown rod and neutron absorbers, a reactor shutdown rod drive mechanism, and units of neutron absorber drive mechanism. The reactor shutdown rod drive mechanism causes an inner extension tube to fall and release the reactor shutdown rod by a gripper section by turning off the power supply to a holding magnet at the time of scram. When grasping the neutron absorbers, an outer extension shaft is pulled up to allow both of the extension shafts to be inserted. After the outer extension tube gets to a handling head section of the neutron absorber, the outer extension shaft is pushed down to grasp the neutron absorber externally by latch fingers of the gripper section so that the neutron absorber can be moved up and down.

Abstract: In a fast breeder reactor provided with a core comprising a core region packed with a fissile material and a blanket region which surrounds the outside of said core region and most of which is formed of a fertile material, and a plurality of control rods which are put in and out of the above core region by a control rod driving device, the fast breeder reactor of the present invention is characterized in that each of said control rods is constructed of a neutron absorber region packed with a neutron absorber and a gas region disposed in the end portion on the side further separated from said control rod driving device than said neutron absorber region. With this invention, the spectral shift effect can be produced by utilizing said gas region, thereby increasing the core reactvity of the fast breeder reactor.