Abstract: The present invention relates to devices and methods for measuring neutron fluence at a pre-selected location which is positioned in a nuclear power plant. The devices and methods include passing neutrons through a fiber optic cable. The fiber optic cable has disposed therein a neutron sensitive material which is capable of absorbing the neutrons to produce a gas. The gas results in a build-up of pressure in the fiber optic cable which causes a change in the optical stress birefringence pattern. This change is measured and used to determine the amount of gas in the fiber optic cable, the number of neutrons absorbed by the neutron sensitive material and subsequently, the neutron fluence at the pre-selected location. In particular, the devices and methods of the invention are effective without the need to employ a radioactive material.

Abstract: A vacuum micro-electronics device that utilizes fissile material capable of using the existing neutron leakage from the fuel assemblies of a nuclear reactor to produce thermal energy to power the heater/cathode element of the vacuum micro-electronics device and a self-powered detector emitter to produce the voltage/current necessary to power the anode/plate terminal of the vacuum micro-electronics device.

Abstract: An in-core nuclear detector for detecting the neutron population surrounding the detector. The detector is an ion chamber having a cylindrical outer electrode that is insulated from a central electrode and capped to contain an Argon gas. An electron radiator that produces prompt neutron capture gamma radiation that is substantially, directly proportional to the local neutron population is disposed between the outer tubular electrode and the central electrode.

Abstract: A pulsed sonar-based wireless rod position indication system that utilizes nuclear radiation and high temperature tolerant hardware. The pulsed sonar-based rod position indication system can precisely locate the rod position by measuring the time of flight of a transmitted signal and by using the phase and amplitude information of the same transmitted signal. Primary and secondary antenna probes located in the interior of the control rod drive rod travel housing and full hardware redundancy provide for improved accuracy. The time of flight, phase and amplitude raw signals are inputted to a wireless data transmitter capable of sending the raw signals to a receiver antenna located elsewhere inside a containment for further processing.

Abstract: A means for installing material, through a fuel assembly instrument thimble insert, into the existing instrument thimbles in nuclear fuel assemblies for the purpose of allowing the material to be converted to commercially valuable quantities of desired radioisotopes during reactor power operations during a remainder of a fuel cycle and removing the radioisotopes from the core through the reactor flange opening once the fuel assemblies have been removed for refueling. The invention also describes methods that can be used to harvest the irradiated material so it can be packaged for transportation from the reactor to a location where the desired radioisotope(s) can be extracted from the fuel assembly instrument thimble insert.

Abstract: A device that will enable material to be irradiated as needed to produce a desired transmutation product inside the core of a nuclear reactor. The device provides a means for monitoring neutron flux in the vicinity of the material being irradiated to allow determination of the amount of transmutation product being produced. The device enables the irradiated material to be inserted into the reactor and held in place at desired axial positions and to be withdrawn from the reactor when desired without shutting down the reactor. The majority of the device may be re-used for subsequent irradiations. The device also enables the simple and rapid attachment of unirradiated target material to the portion of the device that transmits the motive force to insert and withdraw the target material into and out of the reactor and the rapid detachment or the irradiated material from the device for processing.

Abstract: A silicon carbide Schottky diode solid state radiation detector that has an electron donor layer such as platinum placed over and spaced above the Schottky contact to contribute high energy Compton and photoelectrical electrons from the platinum layer to the active region of the detector to enhance charged particle collection from incident gamma radiation.

Abstract: A system that measures the temperature distribution of the reactor coolant flowing through the hot leg or cold leg pipes by measuring the speed of sound time delay. This concept uses radiation hardened and temperature tolerant ultrasonic signal drivers based on vacuum micro-electronic technology. The system employs ultrasonic signals propagated through water, and relies on the characteristic that the speed of sound changes as the density and temperature of the water changes. Thus, a measured difference in the speed of sound in water may be directly correlated to a temperature change of the water.

Abstract: A method and a system for performing real-time, continuous, measurements of the boron concentration in the water entering a nuclear reactor coolant system. The invention utilizes knowledge of the impact that boron contained in liquid water has on the attenuation of acoustic or ultrasonic waves. This information, coupled with radiation damage resistant and high temperature operability capable transmitter and receiver equipment, provides the means to place the measurement system sensors and signal processing electronics on the reactor coolant system charging flow piping or the hot leg or cold leg of the reactor coolant loop. This will allow the reactor operator to directly monitor both the reactor coolant system boron concentration value and detect changes in the reactor coolant system boron concentration relative to a reference value as they occur.

Abstract: A method for monitoring changes in the boron concentration in the coolant of a reactor during a nuclear plant outage that applies temperature compensation to the source range detector output. The method then monitors the compensated output signal to identify changes in the detector count rate above a preselected value.

Abstract: A pulsed sonar-based wireless rod position indication system that utilizes nuclear radiation and high temperature tolerant hardware. The pulsed sonar-based rod position indication system can precisely locate the rod position by measuring the time of flight of a transmitted signal and by using the phase and amplitude information of the same transmitted signal. Primary and secondary antenna probes located in the interior of the control rod drive rod travel housing and full hardware redundancy provide for improved accuracy. The time of flight, phase and amplitude raw signals are inputted to a wireless data transmitter capable of sending the raw signals to a receiver antenna located elsewhere inside a containment for further processing.

Abstract: Apparatus for amplifying low level signals within a nuclear plant's containment building, derived from the ex-core nuclear instrumentation system. The system employs vacuum micro-electronic devices in place of conventional pre-amplifier assemblies to position the pre-amplifier assemblies closer to and within the vicinity of the ex-core detector outputs.

Abstract: A subcritical reactivity monitor that utilizes one or more primarily gamma sensitive (prompt responding) self-powered detector style radiation measurement devices located within the core of a nuclear reactor to determine the amount that the reactor multiplication factor (Keff) is below the reactivity required to achieve or maintain a self-sustaining nuclear chain reaction. This invention utilizes measured changes in the self-powered detectors' current(s) to allow a reactor operator to measure the value of Keff at essentially any desired interval while the reactor is shutdown with a Keff value less than the critical value of 1.0. This invention will enable integration of the output of the value of Keff directly into the Reactor Protection System, which will enable the elimination of the operational and core design analysis constraint costs associated with the current Boron Dilution Accident prevention methodology and enable automatic control of the Chemical Volume Control System.

Abstract: A solid state electrical generator that is responsive to a relatively low level radiation field to power emergency equipment in a nuclear powered generating facility. The electricity is generated from materials, that are not initially radioactive, that are able to produce electrical power when placed inside a relatively low neutron and/or gamma radiation field and will essentially breed material to enhance the power produced by the device sufficiently to allow the device to provide sufficient power to the emergency equipment, even though the reactor or other source of neutron and/or gamma radiation has shut down.

Abstract: A method of determining structural defects in a component that utilizes neutron activation of a solution having the ability to penetrate small cracks on the surface of a material via capillary absorption that produces a discernable prompt gamma release of a defined energy when exposed to a neutron pulse. The intensity of the gamma rays produced at the desired energy at a user controlled position on the surface is used to determine the crack location, length and depth.

Abstract: A magneto-rheological filter/reflector that controls the transmissivity of any form of electromagnetic or particulate radiation through the filter by varying discrete electromagnetic fields across a magneto-rheological fluid. In one embodiment, the filter/reflector controls the rate of the nuclear reaction within the core of a reactor without any moving parts.

Abstract: A telescoping guide for extraction and reinsertion support handling of in-core instrument thimble assemblies in the area above the upper support plate in the upper internals of a pressurized water reactor. The telescoping guides extend between the upper ends of the upper internals support columns and an axially movable instrumentation grid assembly which is operable to simultaneously raise the telescoping guides and extract the in-core instrument thimble assemblies from the reactor fuel assemblies.

Abstract: A nuclear power distribution measurement assembly that is sized to fit within an instrumentation thimble of a nuclear fuel assembly, that employs a spaced tandem arrangement of thermo-acoustic engines, each of which has a heat source side that is insulated from the reactor coolant traversing the nuclear core in which the fuel assembly is to be placed and a cold side housing a resonator chamber with enhanced thermal conductance to the coolant. The resonator chamber of each of the thermo-acoustic engines is of a different length to generate a different frequency whose amplitude is proportional to the neutron activity at the axial and radial position of the thermo-acoustic engine. The frequency identifies the measurement assembly's position. Acoustic telemetry is employed to monitor the acoustic waves generated by the individual thermo-acoustic engines to provide a remote reading of the axial and radial power distribution of a reactor core.

Abstract: A system and method for employing the in-core movable detectors of a commercial nuclear powered electric generating facility to transmute a user-specified target material into a desired isotope. The process is conducted remotely resulting in a shielded end product available for shipment for further processing.

Abstract: A telescoping guide for extraction and reinsertion support handling of in-core instrument thimble assemblies in the area above the upper support plate in the upper internals of a pressurized water reactor. The telescoping guides extend between the upper ends of the upper internals support columns and an axially movable instrumentation grid assembly which is operable to simultaneously raise the telescoping guides and extract the in-core instrument thimble assemblies from the reactor fuel assemblies.