JP2569001B2 - Annular magnetic field type electromagnetic flow coupler - Google Patents

Description

The present invention relates to an electromagnetic fluid device such as an electromagnetic pump or an electromagnetic flow coupler for driving a conductive fluid such as a fluid metal.

[Conventional technology]

The electromagnetic flow coupler arranges two adjacent flow channels perpendicular to the parallel magnetic field, and forcibly flows a conductive fluid such as liquid sodium into one of the flow channels to generate a current. That is, it is made to function as a generator. The other flow path drives the conductive fluid by the induced current and the magnetic field to function as a pump. In the following description, the former will be referred to as a generator-side flow path, and the latter will be referred to as a pump-side flow path.

As described in JP-A-59-10163 (see FIG. 3), the center of a rectangular duct is made of a good conductor partition wall.
The upper part is used as a pump-side flow path 2 and the lower part is used as a generator-side flow path 3. The magnets 4 and 5 are arranged so as to sandwich the flow path from the left and right, and a parallel magnetic field is generated in the flow path. The outer periphery of the flow path is electrically rectangularly formed using the electrode 6, and the current (drive current) generated in the generator-side flow path 3 passes through the pump-side flow path, passes through an external circuit, and then flows through the generator. It is returned to the side channel 3. An insulating material 7 is lined on both sides of the upper and lower flow paths to prevent leakage of the drive current.

The operating principle of this rectangular flow path type electromagnetic flow coupler is described in
This will be described with reference to FIG. 4 and FIG. The conductive fluid in the generator-side flow path in FIG. 3 is forcibly caused to flow by an external force in a direction perpendicular to the paper surface and from the back to the front. As described above, when the conductor is moved perpendicularly to the magnetic field, an electromotive force is induced in the conductor by the Fleming's right-hand rule, and a current is generated. The direction of the current is perpendicular to both the magnetic field and the direction of movement, as shown in FIG. In the case of the flow coupler shown in FIG. 3, the direction is from the bottom to the top of the figure. The current generated in the generator-side flow path 3 flows into the pump-side flow path 2 through the central partition wall 1 in this manner. In the pump-side flow path 2, a current flows in a magnetic field, and a pump force is generated. This phenomenon is known as Fleming's left-hand rule. The direction of the force is perpendicular to both the magnetic field and the current as shown in FIG. In FIG. 3, the direction is perpendicular to the plane of the paper and goes from the front to the back. The fluid is driven by this force. That is, without using a mechanical drive mechanism such as a piston or an impeller, the other fluid can be driven only by flowing the fluid from one.

The use of an electromagnetic flow coupler having the above-described characteristics in a tank-type fast amplification furnace shown in FIG. 5 will be considered. As shown in FIG. 5, in the tank type fast reactor, the reactor core 8
Is transported to the intermediate heat exchanger 9 by the liquid sodium driven by the pump 10. The generated heat is transported to secondary sodium in the heat exchanger 9. The sodium in the secondary system is driven by the pump 11 and flows into the steam generator 12, and exchanges heat with the water side of the steam generator 12. The steam generated by the steam generator 12 flows into the turbine and operates the generator. As shown in FIG. 6, an electromagnetic flow coupler 13 can be installed in the tank instead of the primary system pump 10, and a secondary system sodium (conductive fluid) can be used as a driving source.
As described above, the electromagnetic flow coupler has no maintainable parts such as an impeller and has excellent maintainability, and can improve the reliability and safety of the tank type fast reactor.

As a conventional device of a type different from the above-mentioned rectangular type, see Nucl Energy, 1981, Vol.
b., No1 Some of them use an annular duct, such as p79 to p90. In the case of this flow coupler, as shown in FIG. 7, the duct is divided into two in the circumferential direction by the partition wall 1 of a good conductor. The upper channel in FIG. 7 is a pump-side channel 2,
The lower part is the generator-side flow path 3. The arrangement of the magnetic poles is completely different from the rectangular type. In this case, in order to generate a radial (radial) magnetic field, magnets 4 and 5 are provided at the center and the outer periphery of the flow path. FIG. 7 shows a case where the flow path goes from inside to outside. The operation principle of this annular flow path type flow coupler will be described. The driving fluid of the generator-side flow path 3 is caused to flow by an external force in a direction perpendicular to the paper surface of FIG. The magnetic field is radial but perpendicular to the direction of fluid motion. Accordingly, an electromotive force in the tangential direction on the circumference is generated at each point of the flow path (Fleming's right hand rule). Similarly, the current is directed in the tangential direction on the circumference, so that if all the points on the flow path are connected, a counterclockwise loop is formed. This current flows through the partition 1 into the pump-side flow path 2. If the current remains in a loop, the current and the magnetic field are also orthogonal, so a driving force is generated and the fluid is driven (Fleming's left-hand rule). The direction of the force is perpendicular to the paper surface in FIG. 7, and is the direction from the front to the back. Although the principle is as described above, there is actually no factor for keeping the current in a loop on the pump side. Accordingly, the flow path is not divided into two as shown in FIG. 7 but is divided into small parts as shown in FIG. 8 so that a loop current is obtained.

Yet another type of device has been devised.
This uses a fan-shaped permanent magnet, as described in Japanese Patent Application No. 54-130723. FIG. 9 and FIG.
Figure 10 shows. As shown in FIG. 9, a fan-shaped magnet 15 and a fan-shaped channel 16 are arranged alternately in one large circular tube 14. Inside the fan-shaped channel, circular tubes 17 having a small diameter are arranged so as to be in contact with each other, and electrodes 18 are attached to both ends thereof. In the case of this device, the inside of the small circular pipe 17 corresponds to the pump-side flow path, and the remaining part is the generator-side flow path. The operating principle of this fan-shaped electromagnetic flow coupler will be described with reference to FIG. Fan-shaped channel 16
The driving fluid in the (generator side) is caused to flow in a direction perpendicular to the paper surface from the back to the front. The magnetic field is almost parallel in the flow path and is orthogonal to the direction of fluid movement. Therefore, an outward electromotive force is induced according to the Fleming's right-hand rule, and current flows outward. When the current reaches the outer electrode, the current then flows inward through the pump-side flow path formed of the tubes 17. Thereby, a driving force is generated in the fluid in the circular pipe 17 according to the Fleming's left hand rule. The direction of the force is perpendicular to the plane of the paper and is from the back to the front. That is, the generator-side fluid and the pump-side fluid flow in the same direction.

[Problems to be solved by the invention]

In the development of a fast amplification furnace, reduction of the construction cost is an urgent issue at present, and the tank-type fast reactor requires a smaller tank. For this reason, it is promising to provide an electrode flow coupler having not only a pump function but also a heat exchange function in the tank.

Considering that electrode flow couplers are installed around the reactor core in the tank, in the case of a rectangular flow path type electromagnetic flow coupler, it is necessary to install a plurality of coupler units 13 as shown in FIG. Therefore, as compared with the case of the electromagnetic flow coupler 13 having an annular flow path shown in FIG. 12, there is a disadvantage that the tank becomes large in order to secure the same flow path area.

One of the causes for reducing the efficiency of the electromagnetic flow coupler is a braking effect of a leakage magnetic flux. It is assumed that a magnetic field exists outside the electromagnetic flow coupler 13 as shown in FIG. FIG. 13 shows the pump-side flow path 2 of the rectangular electromagnetic flow coupler.
Is a sectional view taken along a plane parallel to the magnetic field and perpendicular to the drive current. Since the drive current does not flow in the leakage magnetic flux portion outside the electromagnetic flow coupler 13, no drive force acts on the fluid in this portion. Since the conductive fluid flows by receiving the driving force in the electromagnetic flow coupler 13, the leakage magnetic flux region at the entrance and exit functions as a generator according to Fleming's right-hand rule, and the fluid has a force opposite to the flow, that is, a braking force. Will work. Next, as shown in FIG.
Let's consider a case where zero was ideally obtained at both ends of. In practice, there is always a leakage flux. FIG. 14 is parallel to the drive current,
FIG. 4 shows a sectional view taken on a plane perpendicular to the magnetic field. As described above, an electromotive force is generated in the conductive fluid in the generator-side flow path 3 by Fleming's right-hand rule. On the other hand, a driving force is generated in the fluid in the pump side flow path 2 according to the left-hand rule, and the flow due to this driving force interacts with an orthogonal external magnetic field to generate a back electromotive force according to the right-hand rule. become. Actually, the sum of the ohmic loss (current × resistance) of the electromotive force on the pump side, the back electromotive force on the generator side, and the drive current in the fluid is balanced. From a different point of view, this back electromotive force acts as an electric resistance, there is no magnetic field at both ends of the coupler, there is no this back electromotive force, and the drive current from the pump side flows through this portion. This bypass current at both ends of the generator-side flow path 2 does not contribute to the driving of the fluid because of the absence of a magnetic field, resulting in a loss.

As described above, in order to increase the efficiency of the electromagnetic flow coupler, it is indispensable to devise a method of offsetting the magnetic flux density at both ends to offset the above-described braking effect and current bypass effect (also referred to as a terminating effect). is there. In manufacturing an electromagnetic flow coupler, it is one of extremely difficult techniques to optimize a leakage magnetic flux distribution by adjusting a magnet shape or its configuration. On the other hand, in order to increase the drive flow rate and drive pressure (pump head) of the electromagnetic flow coupler, it is necessary to lengthen a uniform magnetic field in the flow path direction. Therefore, in order to improve the performance of the electromagnetic flow coupler, it is necessary to reduce the termination effect and to continuously apply a magnetic field long in the flow direction with one stage magnet instead of multiple stages.

The magnets (both permanent magnet and electromagnetic) of the annular flow path type electromagnetic flow coupler described as the second conventional example apply a radial magnetic field to the annular flow path in the arrangement shown in FIG. As can be seen from the figure, a magnetic circuit is formed by the magnets 4 and 5 and the ferromagnetic body 22 to create a radial magnetic field in the pump-side flow path 2 and the generator-side flow path 3. For this reason, on the N pole 4 side,
An outward magnetic field is generated on the S pole 5 side. Accordingly, the drive current 21 is counterclockwise in the AA 'section (see FIG. 16),
-Flows clockwise in section B '(see Fig. 17). For this reason, in the annular type, it is necessary to separate the N pole and the S pole in order to make the generated driving current independent, in addition to the magnet configuration (separating the N pole and the S pole), the terminal effect at both ends of each magnetic pole. Needs to be corrected. In the annular type, in order to increase the length of the action of the magnetic field in the flow direction, a multi-stage magnet configuration must be used as shown in FIG. 18, and it is necessary to correct the termination effect at each stage.

The third conventional example has an annular structure, and can be compactly arranged around the core. However, since the magnet is arranged in the flow path, it is expected that the flow path area of the conductive fluid is limited and the structure is complicated, which is a serious problem.

It is conceivable that the configuration shown in FIG. 3 is changed to a partially annular shape as shown in FIG. 19 and a plurality of annular shapes are arranged. However, since a magnet exists in the middle of the annular shape, miniaturization due to structural simplification cannot be achieved. .

SUMMARY OF THE INVENTION An object of the present invention is to provide an electromagnetic flow coupler having a simple structure and high efficiency, and in particular, to provide an annular structure which can contribute to miniaturization of a tank type fast reactor and a simple structure. Is to do.

[Means for solving the problem]

Means for solving the above problem is to supply a current induced by a magnetic field from inside the generator-side flow path into the pump-side flow path in a direction orthogonal to the magnetic field and the flow of the conductive fluid in the pump flow path. And a magnetic field generator that applies a magnetic field orthogonal to the current and the flow of the conductive fluid in the two flow paths to the conductive fluid in the two flow paths, and a magnetic field generator in the generator-side flow path. Means for applying a driving force to the conductive fluid, wherein an annular flow path surrounded on the inner peripheral side and the outer peripheral side by a conductive wall as the current path is formed on the inner peripheral side. A partition wall made of an electrically insulating material is provided between the outer peripheral side and the pump side flow path and the generator side flow path, and the two flow paths are alternately arranged via the partition wall made of the electrical insulating material. The pump side flow path and the generator side flow are arranged side by side to form an annular shape. Are formed in an annular shape, and the two annularly formed flow paths are arranged concentrically via a conductive partition as the current path, and the conductive paths in the two flow paths are formed around the outer circumference of the two flow paths. An annular magnetic field type electromagnetic flow coupler characterized in that a winding of the magnetic field generator is wound in a toroidal shape along a flow of an ionic fluid, and the two flow paths are surrounded by the toroidal winding. .

[Action] The action of the above means is that when a magnetic field is applied to each conductive fluid in the pump-side flow path and the generator-side flow path by the toroidal winding of the magnetic field generator, the magnetic field becomes an annular closed loop shape. And pass through both channels. In this state, the conductive fluid in the generator-side flow path is forcibly driven by the means for applying a driving force to the conductive fluid in the generator-side flow path to flow into the generator-side flow path. Since the directions of the flow and the lines of magnetic force are orthogonal to each other, a current is induced in the conductive fluid in the generator-side flow path in a direction orthogonal to the lines of magnetic force according to Fleming's right-hand rule. The current flows into the conductive fluid in the pump-side flow path through the current path, and the current in the pump-side flow path is orthogonal to the magnetic field lines. A driving force according to Fleming's left-hand rule is induced in the conductive fluid in the pump-side flow path in a direction perpendicular to the direction, and the conductive fluid in the pump-side flow path in a direction perpendicular to the current and the lines of magnetic force. Flows. Since the magnetic field generation area by the magnetic field generator that generates the magnetic field lines can be expanded simply by expanding the winding area of the winding in the direction of the flow of the conductive fluid, the magnetic field generator can be extended along the direction of the flow of the conductive fluid. It is no longer necessary to expand the magnetic field generation region by combining in multiple stages, and the occurrence of the termination effect, which is an adverse effect of such multiple combination, is suppressed.

〔Example〕

A first embodiment of the present invention will be described with reference to FIG. 27th
As shown in the figure, the toroidal coil 24 springs at the upper and lower ends of the annular flow path 23. Inflow or outflow 25 of the conductive fluid. As shown in FIG. 1, the inner annular flow path communicating with the generator-side header 36 is referred to as a generator-side flow path 3, and the outer side communicating with the pump-side header 35 is referred to as a pump-side flow path 2. Each head 35, 36 is also provided below each of the flow paths 2, 3, and has a similar communication relationship. As shown in the sectional view taken along the line AA 'in FIG. 2 (see FIG. 2), an external magnetic field 20 exists in the flow path in the circumferential direction due to the toroidal coil (winding 24). Therefore, when the conductive fluid in the generator-side flow path 3 is caused to flow upward from below by an external force, an outward electromotive force is generated according to the Fleming right hand rule. As shown in FIG. 2, the current 21 generated in the generator-side flow path 3 flows through the good conductor partition wall 1 and flows through the conductive fluid in the pump-side flow path 2 and then flows upward or downward at the outer flow path wall. It flows downward, and returns to the conductive fluid in the generator-side flow path from the inner flow path wall through the upper and lower ends. Therefore, the conductive fluid in the pump-side flow path 2 flows by receiving a downward force according to Fleming's left-hand rule. According to the present invention as shown in FIG. 21 or FIG. 23, the length of the external magnetic field in the flow path direction can be as long as necessary by simply increasing the length of the winding. Not required. Further, the present invention is not limited only to the annular flow path, but when applied to a tank type fast reactor due to the annular flow path configuration, it can greatly contribute to downsizing of the tank. Furthermore, it goes without saying that the configuration is simple.

A second embodiment of the present invention will be described with reference to FIG. In this embodiment, the single annular flow path is divided into two by the insulating material partition wall 26,
The generator-side flow path 3 and the pump-side flow path 2 are provided. Figure A-
As shown in the A 'sectional view (see FIG. 29), a circumferentially clockwise magnetic field 20 is generated by the toroidal coil 24. The conductive fluid in the generator-side flow path 3 is caused to flow from the bottom upward by an external force in the front direction from the back perpendicular to the plane of FIG. According to Fleming's right-hand rule, a radially outward current flows in the conductive fluid in the generator-side flow path 3 and returns through the conductive fluid in the pump-side flow path 2 where no electromotive force is generated. A closed circuit passing through the outer pipe wall of the annular flow path is formed. Pump side flow path 2
Flows through the conductive fluid inside.

The current interacts with the orthogonal circumferential magnetic field, which generates an upward driving force in the conductive fluid according to Fleming's left-hand rule, and functions as an electromagnetic flow coupler. This embodiment can provide an annular electromagnetic flow coupler with a relatively simple flow path configuration.

A third embodiment of the present invention will be described with reference to FIGS. 30 and 31. In the present embodiment, a circumferential magnetic field is realized by a solenoid coil 24 instead of the toroidal coil of the first embodiment, and operates similarly. According to the present embodiment, a ring-shaped electromagnetic flow coupler can be realized with a relatively simple coil configuration.

A fourth embodiment of the present invention will be described with reference to FIGS. 32 and 33. In the present embodiment, a circumferential magnetic field is realized by a solenoid coil 24 instead of the toroidal coil of the second embodiment, and has the same function. According to this embodiment, both the flow path and the coil can be realized with a simple configuration.

A fifth embodiment of the present invention will be described with reference to FIGS. 34 and 35. In this embodiment, a heat exchange function is added to the second embodiment having a pump function. As shown in FIG. 36, the annular flow path provided with a closed magnetic field in the circumferential direction by a solenoid or a toroidal coil is divided into multiple sections to increase the contact area of the pump side and the generator side conductive fluid through the partition wall. If there is a temperature difference between the conductive fluid on the pump side and the conductive fluid on the generator side, heat is transferred from the high-temperature side to the low-temperature side and functions as a heat exchanger. According to the present embodiment, a ring-shaped electromagnetic flow coupler having a heat exchanger and a pump function can be realized.

A sixth embodiment of the present invention will be described with reference to FIG. The reactor core 8 of the tank type fast amplification reactor is isolated from the tank side during normal operation by a cylindrical container 32 and a fluid stopper 34. Liquid sodium in the tank is kept at a low temperature. The heat exchange type annular electromagnetic flow coupler 31 circulates sodium on the core side and transports heat generated in the core 8 to secondary sodium. When the flow of the secondary sodium stops, the sodium in the tank flows from the fluid stopper 34 to remove the heat of the core and release the heat through the tank outer wall. According to this embodiment, there is an advantage that the magnet of the electromagnetic flow coupler can be held in a low temperature environment, and the size and cost of the tank can be reduced by the electromagnetic flow coupler in which the pump and the heat exchanger are integrated. FIG. 37 shows the results of a trial calculation of the tank miniaturization when the heat exchange type electromagnetic flow coupler is applied to the currently designed tank type blast furnace (tank diameter: about 20 m). From the viewpoint of securing the primary sodium flow rate, it can be seen that the size of the electromagnetic flow coupler depends on the flow velocity, and as can be seen from the figure, the tank can be downsized to less than 14 m at a flow velocity of 4 m / s.

FIG. 40 shows the pump efficiency evaluation results of the electromagnetic flow coupler with the number of magnet stages N as a parameter. In the analysis results when the entire length of the excitation unit is fixed, the horizontal axis corresponds to the magnetic field strength. From the figure, it is understood that the effect of the termination effect becomes smaller and the efficiency becomes better as the number of stages is smaller.

〔The invention's effect〕

According to the present invention, the length of the action of the magnetic field in the direction of the flow path can be arbitrarily set, so that an electromagnetic flow coupler having a smaller pumping efficiency and a smaller pumping effect than the case of using a multi-stage magnet can be provided. Further, when considering application to a tank-type high-speed amplification furnace, an annular structure can be adopted, which greatly contributes to miniaturization of the tank and can greatly reduce costs.

[Brief description of the drawings]

1 is an explanatory view of an embodiment of the present invention, FIG. 2 is a sectional view taken along line AA 'of FIG. 1, FIG. 3 is an explanatory view of Conventional Example 1, and FIG. 4 is a principle view of an electromagnetic flow coupler. , FIG. 5 is a system diagram of a conventional fast reactor, FIG. 6 is a system diagram in a case where an electromagnetic flow coupler is applied to the fast reactor, FIG. 7 and FIG. FIG. 10 is an explanatory view of Conventional Example 3, FIGS. 11 and 12 are examples of application of an electromagnetic flow coupler to a fast reactor, and FIGS.
FIG. 14 is an explanatory view of the termination effect, FIGS. 15, 16, 17, and 18 are explanatory views of the conventional example 2 in which the magnetic field is of a multistage type,
FIG. 19 and FIG. 20 are explanatory views of the state of deformation of the magnetic field, FIG.
FIG. 22, FIG. 23, FIG. 24, FIG. 25 and FIG. 26 are explanatory diagrams of a toroidal coil and a solenoid coil, FIG. 27 is an explanatory diagram of Embodiment 1, and FIG. FIG. 29 is an AA ′ sectional view of FIG. 28, FIG. 30 is an explanatory view of Embodiment 3, FIG. 31 is an axial sectional view of FIG. 30, and FIG.
33, FIG. 33 is a sectional view taken along the line BB 'of FIG. 32, FIGS. 34 and 35 are explanatory views of Embodiment 5, FIG. 36 is an explanatory view of Embodiment 6, and FIG. FIG. 38 is a graph showing the effect of the present invention, and FIG. 38 is a graph showing the relationship between the pump efficiency and the magnetic flux density of the electromagnetic flow coupler for each number of magnet stages. 1 ... good conductor (conductive) partition wall 2 ... pump side flow path 3
... Generator side flow path, 13 ... electromagnetic flow coupler, 20 ... magnetic field, 21 ... current, 24 ... winding, 26 ... insulating material partition

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tadashi Goto 1168 Moriyamacho, Hitachi, Japan Inside Energy Laboratory, Hitachi, Ltd. Inside the factory Hitachi factory

Claims (1)

(57) [Claims] 1. A current path for supplying a current induced by a magnetic field from a generator-side flow path into a pump-side flow path in a direction orthogonal to the magnetic field and the flow of a conductive fluid in the pump flow path. A magnetic field generator that applies a magnetic field orthogonal to the current and the flow of the conductive fluid in the two flow paths to the conductive fluid in the two flow paths, and the conductive fluid in the generator-side flow path Means for providing a driving force to the electromagnetic flow coupler, wherein an annular flow path surrounded by an inner peripheral side and an outer peripheral side by a conductive wall as the current path is formed on the inner peripheral side and the outer peripheral side. A partition wall made of an electrically insulating material is provided between the two to form the pump-side flow path and the generator-side flow path, and the two flow paths are alternately arranged via the electrically insulating material's partition wall to form an annular shape. Or the pump-side flow path and the generator-side flow path are formed in an annular shape The two annularly formed flow paths are arranged concentrically via a conductive partition as the current path, and are arranged around the outer circumference of the both flow paths along the flow of the conductive fluid in the both flow paths. An annular magnetic field type electromagnetic flow coupler, wherein the windings of the magnetic field generator are wound in a toroidal shape so that the two flow paths are surrounded by the toroidal windings.