Abstract: An ultrasonic transducer specifically suited to high temperature sodium applications is described. A piezoelectric active element is joined to the transducer faceplate by coating the faceplate and juxtaposed active element face with wetting agents specifically compatible with the bonding procedure employed to achieve the joint. The opposite face of the active element is fitted with a backing member designed to assure continued electrical continuity during adverse operating conditions which can result in the fracturing of the active element. The fit is achieved employing a spring-loaded electrode operably arranged to electrically couple the internal transducer components, enclosed in a hermetically sealed housing, to accessory components normally employed in transducer applications.Two alternative backing members are taught for assuring electrical continuity. The first employs a resilient, discrete multipoint contact electrode in electrical communication with the active element face.

Abstract: A visual indicator in parallel with a zener diode, positioned in series with a load is provided to monitor the presence of current flow in a circuit over a range of several orders of magnitude. In addition, a circuit arrangement is described to monitor the continuity and current flow in two separate parallel paths, feeding a common load in order to check the continuity of the circuitry and associated switching devices. For this purpose, a second current monitor, including a series switch, is placed in parallel with a first series arrangement of a current monitor and a switch. Alternate polarity arrangements of the respective zener diodes associated with the corresonding current monitors are illustrated to show the varing modes of operation contemplated by this invention.

Abstract: A microwave fluid flow meter is described utilizing two spaced microwave sensors positioned along a fluid flow path. Each sensor includes a microwave cavity having a frequency of resonance dependent upon the static pressure of the fluid at the sensor locations. The resonant response of each cavity with respect to a variation in pressure of the monitored fluid is represented by a corresponding electrical output which can be calibrated into a direct pressure reading. The pressure drop between sensor locations is then correlated as a measure of fluid velocity.In the preferred embodiment the individual sensor cavities are strategically positioned outside the path of fluid flow and are designed to resonate in two distinct frequency modes yielding a measure of temperature as well as pressure. The temperature response can then be used in correcting for pressure responses of the microwave cavity encountered due to temperature fluctuations.

Abstract: A thermal expansion compensation system for nuclear reactor fuel assemblies is disclosed herein which utilizes materials with different rates of thermal expansion in appropriate components so to: retain alignment of the assembly; reduce or eliminate thermal bow; and reduce or eliminate jump movement of fuel assemblies.

Abstract: A method of automatically monitoring the power distribution of a nuclear reactor during normal power operation employing in-core detectors maintained within the thermal environment of the reactor at a prearranged storage location, normally outside the core reactivity region. The detectors are intermittently inserted into the core region according to a periodic predetermined time program. Upon insertion, the detectors are moved along corresponding preselected linear paths which terminate at the detector storage locations. Detector output vs. position is continuously recorded during travel to provide a partial core flux map.Four detectors, arranged in two electronically redundant groups, are alternately inserted into the core at staggered intervals dictated by the time program to obtain the desired flux information.