Method and apparatus for controlling liquid metal flow

• US 4,824,329 A
• Filed: 06/18/1986
• Issued: 04/25/1989
• Est. Priority Date: 07/05/1985
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Yamamoto, Hajime, Gotou, Tadashi, Nakao, Noboru, Yamakawa, Masanori, Ikeda, Takashi
• Primary Examiner(s): Stout, Donald E.
• Application Number:
  US06/875,680
• Time in Patent Office: 1,042 Days
• Field of Search: 417/50, 417/32, 417/53, 376/171, 376/229, 376/402
• US Class Current: 417/50
• CPC Class Codes: G21C 15/247 for liquid metals
• CPC Class Codes: H02K 44/04 Conduction pumps
• CPC Class Codes: H02K 44/085 with conducting liquids
• CPC Class Codes: Y02E 30/30 Nuclear fission reactors

Abstract

A method comprising the steps of: allowing the directions of a magnetic field, an electric current and the liquid metal flow to perpendicularly intersect to one another; and varying at least one of the magnetic field and the electric current in intensity in response to the temperature of the liquid metal. A force acting on the liquid metal flow is increased and decreased by the interaction between the magnetic field and the electric current. An apparatus for performing the method comprising material varying in electric property with the temperature of the liquid metal. The material is installed in at least one of a path of the magnetic field, a path of the electric current and means for generating the magnetic field. Variation of the electric property of the material allows one of the magnetic field and the electric current to be automatically increased or decreased in intensity in response to the temperature of the liquid metal, so that the force acting on the liquid metal flow is controlled.

Claims

1. A method of controlling a flow of liquid metal comprising the steps of:

generating a magnetic fied along a first direction;

generating an electric current flow along a second direction;

causing liquid metal to flow in a third direction, said magnetic field electric current flow and liquid metal flow all intersecting perpendicularly to one another; and

varying at least one of the magnetic field and the electric current flow intensity in response to a change of temperature of the liquid metal by a member positioned in the middle of one of said paths to cause a change in the intensity of one of the magnetic field and electric current, so that force acting on the liquid metal is increased or decreased.

2. A method of controlling a flow of liquid metal according to claim 1, wherein both of the magnetic field and the electric current are varied in intensity in response to the temperature of the liquid metal.

3. A method of controlling a flow of liquid metal comprising the steps of:

generating a magnetic field along a first direction;

generating an electric current flow along a second direction;

causing liquid metal to flow in a third direction, said magnetic field electric current flow and liquid metal flow all intersecting perpendicularly to one another;

providing a material which varies in electric property with temperature of said liquid metal;

transferring temperature of the liquid metal to said material; and

allowing at least one of the magnetic field and the electric current to pass through said material, so that the intensity of said one is varied so that force acting on the liquid metal is increased or decreased.

4. An apparatus for controlling a flow of liquid metal comprising:

a flow path means for liquid metal located where a magnetic field and an electric current intersect perpendicularly to each other, while the flow path means for liquid metal perpendicularly intersects both the magnetic field and the electric current;

means for generating the magnetic field; and

material varying in electric property with a temperature of the liquid metal and installed in at least one of the path of the magnetic field, a path of the electric current and the means for generating the magnetic field.

5. An apparatus for controlling a flow of liquid metal according to claim 4, wherein the flow path means for liquid metal is surrounded by facing electrodes defining one of a vertical distance and a horizontal distance and by facing electric insultating walls defining the other of the same, and the electric insulating walls are provided therein with electric resistor means which varies in electric resistance with temperature and which is connected to an electric circuit connecting the electrodes.

6. An apparatus for controlling a flow of liquid metal according to claim 4, wherein the flow path means for liquid metal is surrounded all around by duct means made of electrically conductive material, inner surfaces of the duct means are provided in either the vertical or the horizontal direction with electric resistor means which varies in electric resistance with temperature, and magnet means is installed outside of the wall of the duct means in said one of the directions.

7. An apparatus for controlling a flow of liquid metal according to claim 4, wherein the flow path means for liquid metal is surrounded by facing electrodes defining one of a vertical distance and a horizontal distance and by facing magnets defining the other of the same, and coil means is connected to the electrodes and wound around the magnets.

8. An apparatus for controlling a flow of liquid metal according to claim 4, wherein the flow path means for liquid metal is surrounded by facing electrodes defining one of a vertical distance and a horizontal distance and by facing electric insulating walls defining the other of the same, and outside of the electric insulating walls are installed magnets made of material which varies in coercive force with temperature and varies in electric resistance with temperature, the coercive force-temperature characteristic having a tendency opposite to that of the electric resistance-temperature characteristic and the magnets being in electric contact with the electrodes.

9. An apparatus for controlling a flow of liquid metal according to claim 4, wherein the flow path means for liquid metal is surrounded by facing magnets defining one of a vertical distance and a horizontal distance and by facing electric resistors defining the other of the same, the electric resistors varying in electric resistance with temperature, electrodes are installed outside of and in contact with the electric resistors, and an electric power source is connected to an electric circuit connecting the electrodes.

10. An apparatus for controlling a flow of liquid metal according to claim 4, wherein the flow path means for liquid metal is constituted by an inner cylinder and an outer cylinder surrounding an upper portion of the inner cylinder, the inner cylinder is provided therein with heat-transfer pipe means which is connected to air cooler means and passing through horizontal partition means in a reactor vessel of a fast breeder reactor, the outer cylinder is provided with magnet means facing the inner cylinder, and between the magnet means and the inner cylinder is installed electric resistor means which varies in electric resistance with temperature.

11. An apparatus for controlling a flow of liquid metal according to claim 4, wherein the flow path means for liquid metal is constituted by a cylinder provided therein with heat-transfer pipe means which is extended from pipe line means connected to air cooler means and passing through horizontal partition means in a reactor vessel of a fast breeder reactor, magnet means is installed at a center of an outlet of a lower end of the inner cylinder, and between the magnet means and an inner surface of the outlet is installed electric resistor means which varies in electric resistance with temperature.

12. An apparatus for controlling a flow of liquid metal according to claim 4, wherein the liquid metal is liquid metal flowing in pipe line means which connects air cooler means and heat-transfer pipe means installed in a heat exchanger in a reactor vessel of a fast breeder reactor, the liquid metal is surrounded by facing electric resistors defining one of a vertical distance and a horizontal distance and by facing magnets defining the other of the same, the electric resistors varying in electric resistance with temperature, electrodes are installed outside of the electric resistors, and electric power source means is connected to the electric circuit connecting the electrodes.

13. An apparatus for controlling a flow of liquid metal comprising:

a flow path means for liquid metal located where a magnetic field and an electric current intersect perpendicularly to each other, while the flow path means for liquid metal perpendicularly intersects both the magnetic field and the electric current;

means for generating the magnetic field; and

material varying in electric property with a change in temperature of the liquid metal and installed in a path of the electric current wherein the flow path means is for controlling the rate of liquid metal flow and is provided at a center of a cross section of the liquid metal path with one of magnetic substance and magnetic means, having an annular section surrounded by the other of the same, said one of said magnetic substance and said magnetic means being provided with electric resistor means which extends radially in the annular section and varies in electric resistance with temperature.

14. A device for controlling flow of a liquid metal which comprises a flow path for flowing a liquid metal therethrough and a means for generating a magnetic field crossing the direction of said flow at right angles in said liquid metal, the flow rate of said liquid metal being controlled through mutual action between an electric current and said magnetic field generated in said fluid, wherein said device further comprises a material whose electrical resistance varies with the temperature of said liquid metal, said material being provided to influence the effectiveness of at least one of said current and said means for generating a magnetic field for controlling the liquid metal flow.