Abstract: A pump and heat exchanger for pumping a conductive fluid through interaction with a magnetic field and a flowing second conductive fluid. A plurality of tube sets are arranged along radii of a circular annulus formed between two shells. One of the fluids is pumped by conventional means through the radial spaces between the tubes, generating currents and voltages which cause the other fluid to flow within the tubes and in the opposite direction. In magnetic air gap regions of the pump, the tubes are rectangular in shape. As a result of the circular geometry, currents flow circumferentially within the annulus, and voltages are maintained at a low value.

Abstract: A control rod assembly for a nuclear reactor is disclosed having a remotely disengageable coupling between the control rod and the control rod drive shaft. The coupling is actuated by first lowering then raising the drive shaft. The described motion causes axial repositioning of a pin in a grooved rotatable cylinder, each being attached to different parts of the drive shaft which are axially movable relative to each other. In one embodiment, the relative axial motion of the parts of the drive shaft is used either to couple or to uncouple the connection by forcing resilient members attached to the drive shaft into or out of shouldered engagement, respectively, with an indentation formed in the control rod.

Abstract: A method and apparatus for protecting fuel rods in a nuclear reactor core under conditions of a major break in the coolant inlet piping connected to the reactor inlet nozzle. A multi-venturi protector which includes multiple parallel dislosed venturies is mounted in the inlet nozzle. The characteristics of the venturi protector are such that coolant flow through the protector into the reactor is unimpeded, but reverse flow through the protector is restricted when a break occurs in the inlet piping. The resistance offered to such reverse flow permits reactor coolant and emergency core coolant to remain in contact with the reactor core for a time sufficient to allow the fuel rods to decrease in temperature to a low safe level.