KR102070999B1 - System and method for draining of electrically conductive liquid - Google Patents

Abstract

Drainage system of the conductive liquid according to an embodiment, the container portion having a drain port for draining the conductive liquid; And a vortex core suppressor disposed outside the container to suppress generation of a vortex core from the free surface or discharge of the vortex core through the drain port during draining of the conductive liquid. The core suppressor may apply a magnetic field to the conductive liquid to disassemble the 3-dimensional taylor vortex structure in the conductive liquid.

Description

Drainage system and method of conductive liquids {SYSTEM AND METHOD FOR DRAINING OF ELECTRICALLY CONDUCTIVE LIQUID}

The present invention relates to a drainage system and method of the conductive liquid, and more particularly to a drainage system and method of the conductive liquid to dismantle the Taylor vortex structure generated when the conductive liquid is applied by externally draining the conductive liquid.

Free surface vortex flow occurs while the liquid is drained to a small drain. Rotating the container filled with the liquid before draining and then draining creates a dimple or vortex core on the free surface, and shows a gas column in the shape of a columnar column that extends downward to the drain. Free surface vortex flows are observed in continuous casting processes, pumped transport, liquid fuel injection, and the like. However, this vortex flow reduces the mass flow rate of the liquid and introduces unnecessary gas, which reduces mechanical damage and efficiency.

Therefore, methods for suppressing or delaying the generation of free surface vortex flow have been studied.

Gowda et al. Proposed a vortex suppressor in the form of a dish.

Gowda and Udhayakumar used wing form suppressors.

Sohn et al. Analyzed the free surface vortex flow according to the eccentric length through an experimental study in which the drain was placed in an eccentric position rather than the center of the bottom of the vessel.

Ramamurthi and Tharakan proposed stair and bellmouth drains instead of general cylindrical drains and studied the effects of drain holes on vortex suppression through experiments.

The background art described above is possessed or acquired by the inventors in the process of deriving the present invention, and is not necessarily a known technology disclosed to the public before the application of the present invention.

An object according to an embodiment is to simply destroy the 3-dimensional taylor vortex structure generated upon drainage or suction of the conductive liquid by applying a magnetic field from the outside without changing the shape of the container or adding the structure. Or to provide a drainage system and method for conductive liquids that can be dismantled.

An object according to one embodiment is to effectively suppress the generation of a vortex core or air core from the free surface or the discharge of the vortex core or air core through the drainage port during the drainage of the conductive liquid via electromagnetic control. It is to provide a drainage system and method of the conductive liquid capable of.

The objective according to one embodiment is to generate a vortex core from a free surface as the conductive liquid is drained or introduced (sucked), such as a continuous casting process, pumped transport, liquid fuel injection in a rocket engine, sodium cooling fastener (SFR), etc. Applicable in various cases, the present invention provides a system and method for draining conductive liquids that can prevent damage to equipment and reduced efficiency, reduced mass flow of liquids, and deterioration of the final product.

Drainage system for a conductive liquid according to an embodiment for achieving the above object, the container portion having a drain port for draining the conductive liquid; And a vortex core suppressor disposed outside the container to suppress generation of a vortex core from the free surface or discharge of the vortex core through the drain port during draining of the conductive liquid. The core suppressor may apply a magnetic field to the conductive liquid to disassemble the 3-dimensional taylor vortex structure in the conductive liquid.

According to one side, the vortex core suppressor may apply a magnetic field in a direction opposite to the direction of gravity or the drainage of the conductive liquid.

According to one side, the vortex core suppressor may apply a magnetic field in a direction perpendicular to the direction in which the conductive liquid is drained.

According to one side, the vortex core suppressor may include a permanent magnet or an electromagnet.

According to one side, the magnetic field may be applied in a constant direction at a constant intensity during the drainage of the conductive liquid.

According to one side, the magnetic field generates an induced current through interaction with the vortex flow of the conductive liquid, the electromagnetic force or Lorentz force is generated by the interaction of the induced current and the magnetic field, the electromagnetic force or Lorentz force is It may act in a direction opposite to the vortex flow of the conductive liquid.

Drainage method of the conductive liquid according to an embodiment for achieving the above object, draining the conductive liquid through the drain port provided in the container portion; And applying a magnetic field to the conductive liquid, wherein generation of a vortex core from a free surface or discharge of the vortex core through the drain port may be suppressed by the magnetic field during drainage of the conductive liquid. Can be.

According to one side, in the step of applying a magnetic field to the conductive liquid, the magnetic field is applied in a direction opposite to the direction in which the conductive liquid is drained or in a direction perpendicular to the direction in which the conductive liquid is drained, the magnetic field May be applied in a constant direction at a constant intensity during the drainage of the conductive liquid.

According to the drainage system and method of the conductive liquid according to an embodiment, a three-dimensional Taylor vortex structure generated when draining or inhaling the conductive liquid by applying a magnetic field from the outside without changing the shape of the container portion or adding the structure (3-dimensional) The taylor vortex structure can simply be destroyed or dismantled.

According to an embodiment of the drainage system and method of a conductive liquid, the generation of a vortex core or air core from the free surface or the vortex core through the drainage port during the drainage of the conductive liquid through electromagnetic control Alternatively, the discharge of the air core can be effectively suppressed.

According to one embodiment, a system and method for draining conductive liquids may include: a continuous surface casting process, a pumping method, a liquid fuel injection in a rocket engine, a sodium cooling highway (SFR), etc. It can be applied to various cases where vortex cores can be generated from to prevent damage to the machine and reduce efficiency, decrease the mass flow of liquid, and reduce the quality of the final product.

1 illustrates a drainage system of a conductive liquid according to one embodiment.
2 (a) and 2 (b) show the reflex line and the velocity vector over time after the drainage and the streamline of the particles inside the vessel in rotation.
3 illustrates a three-dimensional Taylor Vortex structure.
Figures 4a and 4b shows the vortex core suppression portion is applied to the sodium cooling fastener.
5 shows a state in which the vortex core suppressor is applied to a continuous casting process.
6 is a flowchart illustrating a method of draining a conductive liquid according to an embodiment.
7 (a)-(c) show the development of the free surface according to the Hartmann number.
8 shows the liquid height change during drainage time according to Hartmann number.
9 shows the drainage rate change during the drainage time according to the Hartmann number.
10 (a)-(f) show the velocity vectors and circumferential vortices according to the Hartmann number.
11 (a)-(f) show the dimensionless dislocations on the central plane and free surface at various drainage times when the Hartmann number is 4.5.
12 (a) and (b) show vector plots of current density at various drainage times based on (a) electric field vector and (b) vector product between velocity and magnetic field when the Hartmann number is 4.5.
13 (a)-(e) show three-dimensional current density vectors on a free surface with varying drainage times when the Hartmann number is 4.5.
14 (a)-(c) show vector plots of dimensionless Lorentz forces according to Hartmann number.
15 shows the time change of the mean dimensionless Lorentz force with respect to the Hartmann number.
16 (a)-(f) show the axial speed profile and the swing speed profile according to the Hartmann number.

Hereinafter, embodiments will be described in detail with reference to exemplary drawings. In adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used to refer to the same components as much as possible, even if displayed on different drawings. In addition, in describing the embodiment, when it is determined that the detailed description of the related well-known configuration or function interferes with the understanding of the embodiment, the detailed description thereof will be omitted.

In addition, in describing the components of the embodiment, terms such as first, second, A, B, (a), and (b) may be used. These terms are only for distinguishing the components from other components, and the nature, order or order of the components are not limited by the terms. If a component is described as being "connected", "coupled" or "connected" to another component, that component may be directly connected or connected to that other component, but there is another component between each component. It will be understood that may be "connected", "coupled" or "connected".

Components included in any one embodiment and components including common functions will be described using the same names in other embodiments. Unless stated to the contrary, the description in any one embodiment may be applied to other embodiments, and detailed descriptions thereof will be omitted in the overlapping range.

1 shows a drainage system of a conductive liquid according to one embodiment, and FIGS. 2 (a) and 2 (b) show a reflex line and a velocity vector and a streamline over time after drainage of particles inside a rotating container, Figure 3 shows a three-dimensional Taylor vortex structure, Figures 4a and 4b shows the vortex core restraint applied to the sodium cooling fastener, Figure 5 shows the vortex core restrained applied to the continuous casting process, 6 is a flowchart illustrating a method of draining a conductive liquid according to an embodiment.

Referring to FIG. 1, the drainage system 10 of the conductive liquid according to an embodiment may include a container part 100 and a vortex core suppression part 200.

The conductive liquid L may be accommodated in the container part 100.

At this time, the container portion 100 may be provided in, for example, a cylindrical shape, the shape of the container portion 100 is not limited thereto, and any one may include an internal space in which the conductive liquid L is accommodated. Do.

In addition, the conductive liquid L may include, for example, a liquid metal such as molten metal, liquid sodium, liquid gallium indium tin mixture, liquid fuel, and the like.

At this time, an example of the conductive liquid (L) is not limited thereto, and any one may be used as long as it can be charged by a magnetic field applied by the vortex core suppression unit 200 to generate an induced current.

In addition, the container part 100 may be provided with a drain port 102.

For example, the drain port 102 may be provided under the container part 100 to drain the conductive liquid L to the outside. Alternatively, the drain port 102 may also be used as a suction port or an inlet port, and the conductive liquid L disposed on the upper part of the container part 100 and drained from the other container part outside is inside the container part 100. May be inhaled or introduced.

At this time, the drain port 102 may be provided in the form of a narrow nozzle, or may be provided in a hole shape provided in the nozzle.

Thereby, when the conductive liquid L is drained from the container portion 100 through the drain port 102 or the conductive liquid L is sucked or introduced through the drain port 102 from the outside, the conductive liquid L is A vortex core or air core may be generated from the free surface of the.

In particular, referring to Figure 2 (a), when looking at the pathline of the particles that are rotating inside the container portion 100 in the state that the drainage has not yet progressed, the particles of the free surface is sucked into the center of the vortex core It can be seen descending to the bottom of the container portion 100 riding down the flow. Particles that have migrated to the bottom move toward the sidewalls as they rotate through the bottom wall, and in the upward flow formed around the sidewalls, they exhibit an Ekman spiral suction flow that moves back to the upper layer. This flow characteristic helps to form a strong downdraft in the center of the vessel after draining, thus promoting the vortex core phenomenon.

In addition, referring to FIG. 2 (b), after the drainage, the velocity vector (symmetric axis left) and the streamline (symmetric axis right) over time can be confirmed. At this time, the velocity vector represents the radial velocity and the axial velocity excluding the revolution velocity component.

At the start of the drainage, the axial vector component is distributed throughout the center from the bottom to the free surface. From the beginning of the drainage, a complex Taylor vortex having a central axis in the circumferential direction is formed in the vicinity of the side wall.

As the drainage proceeds, the center and the side wall have different rotational flow structures.In the center, the particles flowing in the vicinity of the side wall form a strong descending vortex with an axial central axis due to the conservation of angular momentum under the influence of the Ekman spiral flow. In the vicinity of the sidewalls, the size of the Taylor vortex is increased and the surrounding conductive liquids tend to be trapped in the Taylor vortex structure having a central axis in the circumferential direction.

As a result, a strong descending momentum generated from the drainage port 102 is transmitted only to the center of the container part 100 so that a vortex core phenomenon occurs in which the vortex core is rapidly sucked toward the drainage port 102.

Accordingly, as shown in FIG. 3, a three-dimensional taylor vortex structure may be generated in the container portion 100 while the conductive liquid L is drained from the container portion 100. .

In this case, the three-dimensional Taylor vortex structure may be provided in a structure in which a Taylor vortex ring rotating in a direction opposite to each other is stacked.

In addition, there is a strong vortex flow (or vortex flow) that penetrates the center of the stacked Taylor Vortex rings and rotates on a vertical axis. Although the stacked ring structure is confused as the drainage proceeds, the container portion 100 contains a conductive liquid that does not directly participate in the drainage while the vortex structure continues to rotate along the circumferential central axis until the drainage is completed. It is clear that the confinement in the sidewall area

By the action of this three-dimensional Taylor vortex structure, the effective diameter of the container part 100 is much smaller than the actual diameter of the container part 100. Further, based on this phenomenon, only the centrally disposed conductive liquid L is rapidly drained, and consequently, a vortex core is formed from the free surface of the conductive liquid L, and thus the vortex core through the drain port 102. Or the air core may be discharged.

As such, the vortex core formed in the conductive liquid L in the container part 100 may be removed or suppressed by the vortex core suppression unit 200.

The vortex core suppression unit 200 may be disposed outside the container unit 100.

In addition, the vortex core suppression unit 200 may be provided as a permanent magnet or an electromagnet, and may apply a magnetic field to the container unit 100, and thus may be applied to the conductive liquid L accommodated in the container unit 100. .

At this time, the arrangement or configuration of the vortex core suppression unit 200 may be any one as long as it can apply a magnetic field to the conductive liquid (L).

For example, the vortex core suppression unit 200 is disposed to surround at least a portion of the outside of the container part 100 including at least one horseshoe-shaped permanent magnet or an electromagnet, or the vortex core suppression unit 200 is It may be spaced apart from each other along the outer side of the container portion 100 including a plurality of straight-shaped permanent magnets or electromagnets.

Alternatively, the vortex core suppression part 200 is formed to extend along the longitudinal direction (or in the Y-axis direction) of the container part 100 from the outside of the container part 100, or along the length direction of the container part 100. (Or in the Y-axis direction) may be spaced apart from each other, and formed to extend along the width direction (or in the X-axis direction) of the container portion 100 from the outside of the container portion 100, or It may be spaced apart from each other along the width direction (or in the X-axis direction).

As described above, the vortex core suppression unit 200 may be disposed in various forms on the outside of the container unit 100 to apply a magnetic field to the conductive liquid L accommodated in the container unit 100.

Specifically, the vortex core suppressor 200 may apply a magnetic field in a direction opposite to the direction in which the conductive liquid L is drained or in the direction of gravity. At this time, since the direction in which the conductive liquid L is drained or the direction of gravity is the -Y axis direction, the direction in which the magnetic field is applied by the vortex core suppressor 200 may be the Y axis direction.

In addition, the vortex core suppressor 200 may apply a magnetic field in a direction perpendicular to the direction in which the conductive liquid L is drained. At this time, since the direction in which the conductive liquid L is drained or the direction of gravity is in the -Y axis direction, the direction in which the magnetic field is applied by the vortex core suppressor 200 may be the X axis direction or the -X axis direction.

As described above, the vortex core suppressor 200 may select or adjust a direction in which the magnetic field is applied to the conductive liquid L in different cases.

When the magnetic field is applied to the conductive liquid L in the vortex core suppressor 200 as described above, the magnetic field generates an induced current through interaction with the vortex flow of the conductive liquid L shown in FIG. 2. Electromagnetic waves or Lorentz forces can be generated through the interaction of induced currents and magnetic fields.

Specifically, as shown in FIG. 3, while the conductive liquid L is drained from the container part 100, the three-dimensional Taylor vortex structure having the stacked structure of the Taylor vortex rings rotating in opposite directions with respect to each other is provided. Since the magnetic field is applied by the vortex core suppressor 200 in a constant direction and a certain intensity, the induced current, or the electromagnetic force or the Lorentz force may also be generated in different directions in the three-dimensional Taylor vortex structure. As such, the vortex core suppression unit 200 may apply a magnetic field to the conductive liquid L in a predetermined direction and a predetermined intensity.

In particular, the electromagnetic force or Lorentz force generated through the interaction of the induced current and the magnetic field may act in a direction opposite to the vortex flow of the conductive liquid L in the three-dimensional Taylor vortex structure. As a result, the vortex flow of the conductive liquid L may be delayed or eliminated. As a result, the three-dimensional Taylor vortex structure generated during the drainage of the conductive liquid L may be destroyed or dismantled by the action of the vortex core suppressor 200.

Therefore, the drainage system 10 of the conductive liquid according to an embodiment controls the electromagnetic force or Lorentz force generated in the conductive liquid L by applying a magnetic field from the outside, that is, through the electromagnetic control, the conductive liquid L 3) Taylor vortex structure generated from the free surface while draining), thereby essentially destroying or discharging the vortex core during the drainage of the conductive liquid L or the discharge of the vortex core through the drain port 102. Can be.

This principle can be applied to various fields.

In particular, referring to FIGS. 4A and 4B, the vortex core suppression unit 200 may be disposed outside the intermediate heat exchanger IHX in a sodium-cooled fast reactor (SFR).

In general, Sodium-cooled Fast Reactor (SFR) is the hot liquid sodium from the core is passed through the intermediate heat exchanger (IHX) in the hot pool area to the cold pool area and then pumped back to the core of the hot pool. It has a circulation structure that is supplied with.

In addition, the upper part of the reactor body in a sodium cooling fastener is filled with argon gas to prevent liquid sodium from making direct contact with air. However, argon gas may be introduced onto the vortex core generated at the free surface by operating the pump in the sodium cooling expressway.

Specifically, the Taylor vortex structure may be generated by the vortex flow rotating in the axial direction while the liquid sodium is sucked into the suction hole H provided in the intermediate heat exchanger IHX, and the vortex core is formed at the center of the Taylor vortex structure. Argon gas may be sucked together into the suction hole (H) provided in the intermediate heat exchanger (IHX).

The argon gas introduced into the intermediate heat exchanger (IHX) may be introduced into the core by circulation of the liquid sodium from the intermediate heat exchanger (IHX) to the core.

In order to prevent this phenomenon, the vortex core suppression unit 200 may be disposed outside the intermediate heat exchanger IHX.

For example, the vortex core suppressor 200 is formed of various types of permanent magnets or electromagnets, and is perpendicular to the longitudinal direction of the intermediate heat exchanger IHX or opposite to the suction direction through the suction hole H. A magnetic field can be applied to the liquid sodium in such a direction.

In addition, the vortex core suppression unit 200 includes a plurality of magnets having different polarities (for example, N poles and S poles), and the plurality of magnets have suction holes H outside the intermediate heat exchanger IHX. It may be positioned higher than), and may be spaced apart from the outside of the path where the vortex core is formed. As a result, the Taylor vortex structure may be dismantled or destroyed so that no vortex core may be generated.

Alternatively, as shown in FIG. 4B, the vortex core suppressor 200 includes a plurality of magnets having different polarities, and different polarities outside the intermediate heat exchanger IHX, particularly outside the hot pool. Alternatingly, a magnetic field can be applied to the liquid sodium evenly outside the intermediate heat exchanger (IHX).

At this time, if liquid sodium is absorbed in the intermediate heat exchanger (IHX), an electromagnetic or Lorentz force can be generated in a direction that can destroy or disassemble the Taylor vortex structure generated from the free surface of liquid sodium, or the direction of the applied magnetic field or The arrangement of the vortex core suppression unit 200 may be various.

As such, the vortex core suppressor 200 may destroy or disassemble the Taylor vortex structure generated from the free surface while liquid sodium is sucked into the intermediate heat exchanger (IHX) by applying a magnetic field outside the intermediate heat exchanger (IHX). Electromagnetic force or Lorentz force can be generated in the same direction, and consequently, argon gas can be prevented from entering the core in the core in the sodium cooling expressway.

In addition, referring to FIG. 5, in the continuous casting process, the vortex core suppression unit 200 may be disposed outside the mold M. Referring to FIG.

At this time, a small drain port P into which the molten metal or the liquid metal discharged from the tundish T flows may be formed on the upper surface of the mold M.

Vortex core phenomenon may occur at the molten surface of the mold in the process of injecting the molten metal into the mold M through the drain port P, and the mold flux in the molten surface may be locally penetrated into the casting, thereby causing a defect in the casting. This may result.

In order to prevent this, the vortex core suppression unit 200 may be arranged to apply a magnetic field in the vertical direction of the mold M. For example, the upper portion of the mold M may be provided to apply the magnetic field downward, or the lower portion of the mold M may be provided to apply the magnetic field upward.

At this time, if the electromagnetic force or Lorentz force can be generated in a direction that can destroy or dismantle the Taylor vortex structure generated from the molten metal while the molten metal is sucked into the mold M, the direction of the applied magnetic field or the vortex core suppressor 200 The arrangement of can vary.

As such, the vortex core suppression unit 200 may generate an electromagnetic force or a Lorentz force in a direction capable of destroying or dismantling the Taylor vortex structure generated from the molten surface while the melt is sucked into the mold M by applying a magnetic field from the outside. As a result, it is possible to suppress the local concentration of the vortex core or the local concentration of the injected flux in the molten mold or the molten metal in a specific position in the casting manufactured in the continuous casting process.

Meanwhile, referring to FIG. 6, the draining method of the conductive liquid may be performed as follows.

First, the conductive liquid is drained through the drain port provided in the container unit (S10), and a magnetic field is applied to the conductive liquid (S20).

At this time, the generation of the vortex core from the free surface of the conductive liquid or the passage of the vortex core through the drain port can be suppressed during the drainage of the conductive liquid by the applied magnetic field.

Further, the magnetic field may be applied in the direction in which the conductive liquid is drained or in the direction opposite to the direction of gravity or in a direction perpendicular to the direction in which the conductive liquid is drained, and may be applied in a constant direction at a constant intensity during drainage of the conductive liquid.

As described above, the direction of the applied magnetic field may be controlled to generate electromagnetic or Lorentz forces in the direction of breaking or breaking up the Taylor vortex structure created in the conductive liquid.

Likewise, the conductive liquid can be inhaled as follows.

First, the conductive liquid is sucked from the outside through the drain port provided in the container, and a magnetic field is applied to the conductive liquid.

At this time, the generation of the vortex core or the inflow of the vortex core in the container portion can be suppressed from the free surface of the conductive liquid during the suction of the conductive liquid by the applied magnetic field.

Further, the magnetic field may be applied in a direction opposite to the direction in which the conductive liquid is sucked or in a direction perpendicular to the direction in which the conductive liquid is sucked, and may be applied in a constant direction at a constant intensity during the suction of the conductive liquid.

As described above, the direction of the applied magnetic field may be controlled to generate electromagnetic or Lorentz forces in the direction of breaking or breaking up the Taylor vortex structure created in the conductive liquid.

As described above, the drainage system and method of the conductive liquid according to an embodiment are described, and the experimental results of the drainage system and the method of the conductive liquid according to one embodiment are described below.

7 (a)-(c) show the development of the free surface according to the Hartmann number.

; 점성력과 전자기력의 비)가 0.45, 4.5인 경우 내부 속도장의 큰 차이점은 발견되지 않는다. 용기부의 중심부에서는 축방향으로 회전하면서 하강하는 흐름이 나타나며, 중심부를 제외한 영역에서는 복잡한 형태의 테일러 보텍스 구조가 형성되어 재순환 흐름을 만든다.Referring to Figs. 7 (a) to 7 (c), the Hartmann number (

; If the ratio of viscous and electromagnetic forces is 0.45, 4.5, no significant difference in the internal velocity field is found. In the center of the container portion, a descending flow appears while rotating in the axial direction, and in a region other than the center, a complex vortex vortex structure is formed to create a recycle flow.

When the Ha number increases to 45, a strong suppression force is acted on by Lorentz force. The axially descending vortex flow at the center and the recirculation flow by the Taylor vortex structure are completely suppressed, resulting in no vortex core phenomena, only high velocity exit flows observed at the outlet.

8 shows the liquid height change during drainage time according to Hartmann number.

Referring to FIG. 8, when a magnetic field is applied, there is no sudden change in the level decrease rate at approximately 8τ ₀ , and vortex core discharge occurs when the magnetic field is not applied.

At a Ha number of 45, the water level decreases 10% faster than at a Ha number of zero. As the Ha number increases, the rate of water level decrease increases.

However, when the Ha number is larger than 4.5, the rate of water level reduction is not affected by the Ha number change, and the water level decreases almost linearly.

9 shows the drainage rate change during the drainage time according to the Hartmann number.

The dimensionless drainage velocity is defined as

At this time,

A _drain is the cross-section of the drain port,

ρ _l is the density of the liquid,

은 순간 배수 유량이다.

Is the instantaneous drainage flow rate.

First, when no magnetic field is applied, the drainage rate decreases rapidly at approximately 8τ ₀ at which the vortex core is discharged, and continues to decrease to 22τ ₀ . Subsequently, the variation in the drainage speed is repeated up to 30τ ₀ . This is believed to be due to intermittent cracking as the vortex core is discharged through the drain port.

At a Ha number of 45, the rate of drainage is shown to decrease linearly with the reduced potential energy of the remaining liquid in the vessel.

For the Ha numbers of 0.45 and 4.5, the drainage rate decreases to 12τ ₀ , but much larger than for the Ha number of zero. In all cases where vortex cores occur, there is a continuous fluctuation in the drainage rate over the entire drainage time. For the Ha numbers 0.45 and 4.5, the emission of the vortex core disappears after a short appearance around 12τ ₀ . This means that the gas is not directly sucked into the drain port when the vortex core is discharged, but the drain flow rate is severely disturbed. Thus, significant instability with respect to the flow rate of the fuel supply system in liquid propulsion engines may occur.

10 (a)-(f) show the velocity vectors and circumferential vortices according to the Hartmann number.

10 (a) to (f), when the Ha number is 45, the Taylor vortex structure appears weak at the early stage of drainage and disappears almost as the drainage proceeds. And a large velocity is detected only near the drain port. If the Ha numbers are 0.45 and 4.5, a vortex structure is created that rotates about the circumferential axis within the vessel, which is almost the same as the Ha number is zero.

The flow structure in the container portion is significantly affected by the current induced by the introduced magnetic field and the strength of the applied magnetic field due to the electromagnetic force generated by the introduced magnetic field, ie Lorentz force. At this time, the force is in a direction perpendicular to the introduced magnetic field and the induced current. Also, the induced current is in a direction perpendicular to both the applied magnetic field and the velocity of the charged particles. Thus, the Lorentz force, which is the vector product between the current and the magnetic field, continuously slows down the charged particles.

11 (a)-(f) show the dimensionless dislocations on the central plane and free surface at various drainage times when the Hartmann number is 4.5.

The spatial gradient of potential is part of an electric field intensity vector and includes a portion of the current generated in the vessel portion. Thus, from the potential distribution shown in Figs. 11A to 11F, it can be expected that the current from the spatial gradient of the electric field will be further weakened as the drainage proceeds.

12 (a) and (b) show vector plots of current density at various drainage times based on (a) electric field vector and (b) vector product between velocity and magnetic field when Hartmann number is 4.5, and FIG. 13 (a) to (e) show three-dimensional current density vectors on the free surface with varying drainage times when the Hartmann number is 4.5.

Referring to Figs. 12 (a) and (b), when Ha number is 4.5, a plane in which the product of the current vector from the spatial gradient of the electric field vector and the cross product of the vector between the velocity and the magnetic field is located away from the floor as the drainage proceeds. Expressed on 2R. As mentioned above, the intensity of the current from the electric field continues to decrease. On the other hand, the current induced by the velocity-magnetic field cross product becomes stronger up to 12τ ₀ and then gradually decreases. Also, the absolute magnitudes of the two current components are quite different. The current caused by the electric field is approximately 1/000 of the induced current. While the induced current is from the center to the side wall of the container, the current from the electric field is directed in the opposite direction.

For reference, with reference to Figs. 13A to 13E, when the Ha number is 4.5, the current density is expressed on the free surface as the drainage proceeds, and the current density becomes maximum at approximately 12? ₀ .

14 (a)-(c) show vector plots of dimensionless Lorentz forces according to Hartmann number.

Referring to Figs. 14 (a)-(c), as the drainage proceeds, a vector of dimensionless Lorentz forces is represented on a plane 2R positioned away from the bottom surface for three different Hartmann numbers. The same vector scale is applied in each case for comparison.

As shown in Fig. 14A, when the Ha number is 0.45, very small Lorentz forces are generated as compared with the other cases, and the vector cannot be discerned at the current scale.

As shown in FIG. 14B, when the Ha number is 4.5, it can be seen that the Lorentz force acts in the clockwise direction opposite to the direction of rotation of the initial container portion. From the current density shown, the Lorentz force is maximized at approximately 12τ ₀ .

As shown in Fig. 14 (c), in the case where the Ha number is 45, a very large electromagnetic force acts in the clockwise direction during the early stage of drainage. By this effect, the rotating flow in the container portion is decelerated very rapidly, and the swirl motion of the liquid in the container portion almost disappears. Thus, the current produced by the vector product between the magnetic field and the velocity is hardly induced, and the Lorentz force hardly appears after the large Lorentz force is applied during the early multiples.

FIG. 15 shows the time change of the mean dimensionless Lorentz force with the Hartmann number.

Referring to FIG. 15, the average dimensionless Lorentz force in plane 2R, located away from the floor, for different Hartmann numbers was monitored according to drainage time.

When the Ha numbers are 0.45 and 4.5, the Lorentz force remains almost constant over most of the draining period.

On the other hand, if the number 45 has a great Ha Lorentz force for early action and drainage, 7τ ₀ continuously reduced to, and reach a certain level to 20τ _0. The Lorentz force between 7τ ₀ and 20τ ₀ when the Ha number is 45 is lower than that when the Ha number is 4.5. When the number of Ha increases tenfold, the Lorentz force increases by one hundredfold when drained. This is because Lorentz force is determined by the product of the current density induced by the magnetic field and the magnetic field strength introduced, and the magnitude of the induced current is proportional to the magnetic field strength introduced from the outside.

16 (a)-(f) show the axial speed profile and the swing speed profile according to the Hartmann number.

Referring to Figures 16 (a)-(f), the axial and pivot speed profiles on a plane 2R located away from the floor can be plotted according to different Ha numbers.

When the Ha number is 0.45 as compared with the Ha number 0, the Lorentz force is weak and does not show a significant difference.

However, with a Ha number of 4.5, a slightly reduced turning speed is found near the center by the Lorentz force.

The rotational velocity profile disappears completely at a Ha number of 45 at which a very large Lorentz force is applied. By the disappearance of this turning momentum at the center, no Taylor Vortex structure is generated in the container portion and the axial velocity is not varied.

Although embodiments have been described with reference to the accompanying drawings as described above, various modifications and variations are possible to those skilled in the art from the above description. For example, the described techniques may be performed in a different order than the described method, and / or components of the described structure, apparatus, etc. may be combined or combined in a different form than the described method, or may be combined with other components or equivalents. Appropriate results can be achieved even if they are replaced or substituted.

10: drainage system of conductive liquid
100: container
102: drain port
200: vortex core restraint

Claims (8)

A container portion having a drain port for draining the conductive liquid; And
A vortex core suppression unit disposed outside the container unit and configured to suppress a vortex core according to the discharge of the conductive liquid through the drain port during the drainage of the conductive liquid;
Including,
The vortex core suppressor
A first magnetic field generating element disposed above the container portion along a draining direction of the conductive liquid; And
A second magnetic field generating element disposed below the container portion along a draining direction of the conductive liquid,
The vortex core suppressor is configured to differently select or adjust the direction of applying a magnetic field to the conductive liquid,
The first magnetic field generating element and the second magnetic field generating element apply a magnetic field to the conductive liquid in a direction opposite to the drainage direction of the conductive liquid, whereby the magnetic field interacts with the vortex flow of the conductive liquid. Generates an induced current through the interaction between the induced induced current and the magnetic field to generate an electromagnetic force or Lorentz force, and the electromagnetic or Lorentz force acts in a direction opposite to the vortex flow Drainage system for conductive liquids where conventional Taylor Vortex structure is dismantled.
delete delete The method of claim 1,
Wherein said first magnetic field generating element and said second magnetic field generating element comprise a permanent magnet or an electromagnet.
delete delete delete delete

Images