Liquid metal electromagnetic flow control device incorporating a pumping action

In combination with a nozzle constructed of nonconductive material, being connected to a source of liquid metal and defining an orifice for the flow of liquid metal from said source through said orifice, a liquid metal electromagnetic flow control device for controlling the flow of liquid metal through said nozzle orifice, said device comprising:

• (a) an alternating current electromagnetic coil disposed adjacent said nozzle and surrounding but displaced radially outward from said orifice, said coil being operable to produce a magnetic field being axially directed and eddy currents being azimuthally directed within said orifice of said nozzle and the liquid metal flowing therethrough, said coil having opposite ends and a midpoint located therebetween;
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• (b) a nonconductive structure sized to extend across said orifice of said nozzle and occupy an axial portion thereof extending along approximately one-half of the extent of said coil from said midpoint to one of said opposite ends thereof, said structure defining axially extending flow regions and axially extending nonflow regions through said portion of said orifice occupied by said structure, said nonflow regions of said structure being positioned axially adjacent to said flow regions thereof and said axially directed magnetic field produced by said coil so as to substantially block production of eddy currents in the liquid metal as it flows through said axially extending flow regions of said structure and thereby reshape the magnetic field within said orifice at a region of transition therewithin between said portion of said orifice occupied by said structure and a portion of said orifice unoccupied by said structure to have a radially directed component which produces a substantially axially directed pumping force in only one of two opposite axial directions so as to either impede or assist flow of liquid metal through said orifice depending upon which one of said halves of said coil said structure extends along and the location of said unoccupied portion of said orifice in relation to said one of said coil halves.

An electromagnetic flow control device for controlling a flow of liquid metal, comprising:

• (a) an alternating current electromagnetic coil defining an axially extending central space for flow of liquid metal therethrough, said coil being operable to produce a magnetic field being axially directed through said central space and said liquid metal flow and to produce eddy currents being azimuthally directed within the flow of liquid metal;
• and
• (b) a nonconductive structure adapted to be disposed within said coil and along a portion thereof so as to occupy an axial portion of said space through aid coil and leave an adjacent portion of said space unoccupied by said structure, said structure defining axially extending flow regions and axially extending nonflow regions through said structure and said occupied portion of said space, said axially extending nonflow regions of said structure being positioned axially adjacent to said flow regions thereof so as to substantially block production of eddy currents in the liquid metal as it flows through said flow regions of said structure and thereby reshape the magnetic field within said space at a region of transition therewithin between said axially extending occupied and unoccupied portions of said space to have a radially directed component which produces a substantially axially directed pumping force in said space which controls the flow of liquid metal therethrough.