JP2006292073A - Jet creating device and method, and actuator comprising the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact light-weight jet creating device, its method and an actuator comprising the same capable of creating jet in liquid by applying DC voltage to a device of a simple structure. <P>SOLUTION: This jet creating device is created in such a manner that an electrode 1 is provided with a bubble retaining portion 6 for retaining bubbles generated by application of voltage by projecting an insulating body 5 into the liquid 4 from an end portion of the electrode, near the electrode end portion, the electrode 1 and an electrode 2 are mounted in the liquid 4 to generate electric field of inequality by application of voltage, a liquid contact area of the electrode 1 is smaller than the electrode 2 and has a dimension to be covered by the generated bubbles, the voltage is applied to the liquid 4 by the electrode 1, the electrode 2 and a power source 3 to generate the bubbles near the end portion of the electrode 1, the bubbles are retained at the bubble retaining portion 6, and the retained bubbles are explosively evaporated to generate jet in the liquid 4. <P>COPYRIGHT: (C)2007,JPO&amp;INPIT

Description

  The present invention is applied to an inkjet ink discharge, a liquid atomization device, an actuator using the kinetic energy of a jet, a propulsion device using the reaction of the jet, and the like, and a jet generation method thereof, The present invention relates to an actuator including the device.

  The technique relating to the liquid ejection method is applied to, for example, inkjet ink ejection, a liquid atomizing device, an actuator that uses kinetic energy of a jet, a propulsion device that uses the reaction of a jet. For example, as a method of generating a jet flow in this liquid, there is a method of generating a flow in water by electrolyzing water by electricity and electrolyzing it and evaporating it by a reaction after electrolysis. According to this method, a large water motion can be generated using only electricity.

  Patent Document 1 discloses a technique relating to a discharge method for discharging a liquid by generating bubbles by thermal energy, a liquid discharge unit, and an ink jet recording apparatus using the unit. In this liquid ejection method, a technique for improving the efficiency of foaming and eliminating the influence of thermal energy on the ejection medium is disclosed.

  Specifically, the ejection medium and the foaming medium are formed of media having different properties suitable for the respective purposes, and these are held in a state separated in the liquid channel via the interface. Then, the position of the interface that moves in accordance with the discharge operation is controlled by the medium flow flowing through the liquid passage and the flow path so that it is always in front of the heating element when bubbles are generated. Thereby, bubbles are generated only in the foam medium, and the pressure generated by the generated bubbles acts on the discharge medium, and the discharge medium discharges.

  Further, Patent Document 2 uses an ink ejection method in which an ink is electrolyzed in an inkjet recording apparatus to generate a mixed gas of hydrogen and oxygen, and droplets are ejected by volume expansion in which the mixed gas is to be burned. A technique related to an ink jet recording apparatus has been disclosed.

On the other hand, Patent Document 3 discloses a technique relating to an electrically responsive fluid having an EHD (Electro Hydro Dynamics) flow effect and a fluid device using the fluid. It has been well known that liquid flow occurs when a DC high voltage is applied by immersing a metal electrode in a certain fluid, and this phenomenon is called an EHD flow effect. A fluid device that generates a liquid flow utilizing the EHD flow effect can constitute a pump or an actuator using the fluid device as a power source.
JP-A-6-305143 JP-A-4-107148 JP 2004-68898 A

  However, in the technology relating to the ejection device and the ejection method for ejecting liquid by generating bubbles by thermal energy, the electrolysis of ink in accordance with the problem of bubble foaming efficiency or the growth of bubbles as disclosed in Patent Document 2. There is a problem that it is necessary to control the voltage supplied at the stage of combustion. In addition, there is a problem of realizing a small and lightweight actuator that obtains power by discharging liquid.

  In view of the above problems, the present invention is a small, lightweight jet capable of generating a jet in a liquid by applying a DC voltage to a device having a simple structure without complicated voltage control. An object of the present invention is to provide a generation device, a jet generation method thereof, and an actuator including the device.

  According to the first aspect of the present invention, there is provided a first electrode made of a conductive material disposed in a specific first liquid and having a predetermined portion covered with an insulator, and a conductive material disposed in the first liquid. A second electrode made of a material, and a power source connected to each of the first and second electrodes with different polarities, and applying a voltage to the first liquid to generate bubbles, A jet generating device for generating a jet in the liquid of the first liquid, wherein the first electrode is generated by applying the voltage by causing the insulator to protrude into the first liquid from an end of the electrode. A bubble holding unit for holding bubbles in the vicinity of the first electrode end portion is provided, and the first and second electrodes are configured to generate an unequal electric field by applying a voltage from the power source. The liquid contact area in the first electrode is arranged in the liquid, and the second electrode The first liquid is applied to the first liquid by the first and second electrodes and the power source, and the end of the first electrode is reduced. A jet generating device that generates the bubbles in the first liquid by generating the bubbles in the vicinity of the unit, holding the bubbles in the bubble holding unit, and evaporating the held bubbles explosively. Features.

  The invention according to claim 2 is the jet flow generating device according to claim 1, wherein the applied voltage is such a voltage that an electric field strength in the bubble is equal to or higher than a dielectric breakdown electric field of the bubble.

  According to a third aspect of the present invention, the first liquid of the jet flow generating device and a second liquid having a specific gravity different from that of the liquid are stacked so that the first liquid near the interface is formed. The first electrode and the second electrode are arranged so as to cause a flow in the liquid, and the flow in the second liquid is caused by the flow of the first liquid in the vicinity of the interface. It is set as the jet flow production | generation apparatus as described in above.

  According to a fourth aspect of the present invention, there is provided the jet generating device according to the third aspect, wherein a wall is provided in the second liquid in the vicinity of the interface in order to form the flow path of the second liquid. Features.

  The invention according to claim 5 comprises at least one jet generating device according to any one of claims 1 to 4, and the impeller rotated by the jet of liquid generated from the jet generating device is the first or The actuator is provided in the second liquid.

  The invention according to claim 6 is the actuator according to claim 5, further comprising a bubble reservoir for collecting bubbles generated from the first or second liquid.

  The invention according to claim 7 is the actuator according to claim 6, wherein the bubble reservoir is arranged in a direction opposite to the gravitational direction with reference to the first electrode where the bubbles are generated.

  The invention according to claim 8 is the actuator according to claim 6 or 7, further comprising a liquefying means for liquefying the bubbles accumulated in the bubble reservoir.

  The invention according to claim 9 is further provided with bubble amount measuring means for measuring the amount of bubbles accumulated in the bubble reservoir, and when the amount of bubbles measured by the means exceeds a predetermined value, 9. The actuator according to claim 8, wherein the actuator is liquefied.

  According to a tenth aspect of the present invention, there is provided a first electrode made of a conductive material disposed in a specific first liquid and having a predetermined portion covered with an insulator, and a conductive material disposed in the first liquid. A second electrode made of a material, and a power source connected to each of the first and second electrodes with different polarities, and applying a voltage to the first liquid to generate bubbles, A jet generating method of a jet device for generating a jet in a liquid of the first method, wherein the voltage is applied to the first electrode by projecting the insulator from the end of the electrode into the first liquid. A bubble holding unit is provided for holding bubbles generated by the first electrode end portion, and the first and second electrodes generate an unequal electric field by applying a voltage from the power source. The liquid contact area of the first electrode disposed in the first liquid The first electrode is smaller than the second electrode and is covered with the bubbles generated by voltage application, and the first and second electrodes and the power source apply a voltage to the first liquid. The step of generating the bubbles near the end of the first electrode, and the bubble holding unit holds the generated bubbles and explosively vaporizes the held bubbles. And a step of generating a jet in the liquid.

  The invention according to claim 11 is the jet generating method according to claim 10, wherein the applied voltage is such a voltage that an electric field strength in the bubble is equal to or higher than a dielectric breakdown electric field of the bubble.

  The invention according to claim 12 is configured such that the first liquid of the jet flow generating device and a second liquid having a specific gravity different from that of the liquid are formed in a laminated shape, and the first liquid near the interface is formed. The step of disposing the first electrode and the second electrode so as to cause a flow in the liquid and causing the second liquid to flow by the flow of the first liquid in the vicinity of the interface. The jet flow generation method according to 10 or 11 is used.

  The invention according to claim 13 is the jet generation method according to claim 12, wherein a wall is provided in the second liquid in the vicinity of the interface to form a flow path for the second liquid. Features.

  According to the present invention, a compact and lightweight jet generating device and its jet generating method capable of generating a jet in a liquid by applying a DC voltage to a device having a simple structure without complicated voltage control. It is possible to provide an actuator that can obtain a large amount of power while being small and lightweight by using the device.

  The best mode for carrying out the present invention consists of a first electrode made of a conductive material disposed in a specific liquid and having a predetermined portion covered with an insulator, and a conductive material placed in the liquid. In a jet generating device, comprising: a second electrode; and a power source in which the first and second electrodes are connected to different polarities, and applying a voltage to the liquid to generate bubbles to generate a jet in the liquid. The first electrode is provided with a bubble holding part for holding bubbles generated by voltage application in the vicinity of the first electrode end by causing an insulator to protrude from the end of the electrode into the liquid. The second electrode is disposed in the liquid so as to generate an unequal electric field by applying a voltage from a power source, and the liquid contact area of the first electrode is smaller than that of the second electrode, and bubbles generated by applying the voltage So as to be covered by the first, By applying a voltage to the liquid by the second electrode and the power source, generating bubbles near the end of the first electrode, holding the bubbles in the bubble holding unit, and evaporating the held bubbles explosively The jet generating device is configured to generate a jet in the liquid.

  Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention is particularly limited in the following description. Unless otherwise described, the present invention is not limited to these embodiments.

(Embodiment 1)
The jet flow generating apparatus of this embodiment is demonstrated below using an accompanying drawing. FIG. 1 is a schematic cross-sectional view of the jet flow generating device of the present embodiment. As shown in FIG. 1, the jet generating device of the present embodiment includes an electrode 1 made of a conductive material surrounded by an insulator 5, an electrode 2 made of a conductive material, and a power source 3 connected to the electrodes 1 and 2. And a liquid 4 to which a voltage is applied. As shown in FIG. 1, the electrode 1 and the electrode 2 are disposed in the liquid 4. In the present embodiment, the shape of the electrode 1 is a needle shape, and the insulator 5 covers the electrode 1 on the needle, but the end portion of the electrode 1 is not covered with the insulator 5. Further, the electrode 2 has a disk shape.

  Further, the liquid contact area between the electrode 2 and the liquid 4 disposed in the liquid 4 is configured to be larger than the contact area between the electrode 1 and the liquid 4. As shown in FIG. 1, the insulator 5 covering the electrode 1 is configured to protrude from the end of the electrode 1. Due to the protrusion of the insulator 5, the end of the insulator 5 has a cylindrical shape that is open to the liquid 4, and the inside of the cylinder is filled with the liquid 4 (the end of the electrode 1 and the protrusion of the insulator 5. A space formed by a contact surface in contact with the liquid 4 is formed, and the bubble holding portion 6 described in detail below is formed.

  Further, in order to prevent discharge from occurring between the electrode 1 and the electrode 2, the electrode 2 is installed at a location sufficiently separated from the distance from the electrode 1 to the farthest part of the bubble holding unit 6. . By installing in this way, it becomes possible to generate discharge between the electrode 1 and the liquid 4. Electrode 1 and electrode 2 are connected to different polarity terminals of power supply 3.

  Next, operation | movement of the jet flow production | generation apparatus of this embodiment is mainly demonstrated below using FIG. 2 (a)-(c). 2A to 2C are diagrams for explaining the operation of the jet flow generating device of the present embodiment. First, when a voltage is applied to the power source 3 shown in FIG. 1, the liquid contact area between the electrode 1 and the liquid 4 is smaller than the liquid contact area between the electrode 2 and the liquid 4 as described above. An unequal electric field is formed between Therefore, the electric field density is higher in the liquid contact part of the electrode 1 than in the liquid contact part of the electrode 2. Therefore, the electric field energy per unit area is larger on the liquid contact surface of the electrode 1. On the liquid contact surface of the electrode 1 shown in FIG. 2A, bubbles (gas) 7 are generated by vaporization of the liquid 4 due to Joule heat due to electric current or by electrolysis. For example, if the liquid 4 is water, hydrogen and oxygen are generated by electrolysis.

  As shown in FIG. 2B, the generated bubbles 7 remain in the bubble holding unit 6 and are not immediately separated from the end of the electrode 1. Then, when the bubble 7 grows and the liquid contact area between the electrode 1 and the liquid 4 becomes smaller and becomes zero, the electrode 1 and the liquid 4 form a capacitor via the bubble 7. Then, as shown in FIG. 2C, when a dielectric breakdown occurs between the electrode 1 and the liquid 4 and a discharge is generated, the liquid 4 is explosively vaporized by an instantaneous current due to the discharge.

  Further, the electrolyzed bubbles 7 are instantaneously burned by the discharge. The volume expansion caused by the vaporization releases the pressure from the bubble holding unit 6 toward the liquid 4. Thereby, the liquid 4 in the vicinity of the bubble holding part 6 is ejected in the direction opposite to the end part of the electrode 1 as shown in FIG. Subsequently, when the explosion ends, the bubble holding unit 6 is in a low pressure state, so that the liquid 4 is sucked and filled with the liquid 4 again. And the electrode 1 and the liquid 4 contact again, and vaporization or electrolysis by Joule heat arises. By repeating the steps as described above, the liquid 4 is ejected.

  Here, for example, when water is used for the liquid 4, the electrode 1 is coated with a single core wire having a diameter of about 0.8 mm, and the power source 3 is a power source with a power capacity of 30 W and an output voltage of 20 kV, the voltage is controlled. A jet can be generated continuously without doing so. Therefore, an electric field and a magnetic field are required in the jet generating device operated by Lorentz force, but according to the present embodiment, a flow can be generated in the liquid only by the electric field. Moreover, even if the electrode 1 and the bubble holding part 6 are small, a large jet can be generated by explosion. In addition, even if the applied voltage is constant, the process of generating bubbles, exploding, and filling the liquid continuously occurs, so that it is not necessary to control the power supply voltage in accordance with the growth of the bubbles 7. Have.

(Embodiment 2)
This embodiment is an application example of the first embodiment. Only the characteristic points of the jet flow generating apparatus of the present embodiment will be described below with reference to FIG. FIG. 3 is a schematic cross-sectional view for explaining the jet flow generating device of the present embodiment. In the present embodiment, the liquid 8 and the liquid 9 having different specific gravities are used for the liquid 4 in the first embodiment. Liquid 8 has a higher specific gravity. The liquid 8 and the liquid 9 form a layer, and an interface is formed between the liquid 8 and the liquid 9. In the liquid 8, the electrode 1 and the electrode 2 of the jet generating device as shown in the first embodiment are installed near the interface.

  Next, operation | movement of the jet flow production | generation apparatus of this embodiment is demonstrated. As shown in FIG. 3, when the electrode 1 and the electrode 2 of the jet generating device are installed, the electrode 1 of the jet generating device generates a flow in the liquid 8, and the flow also generates a flow in the liquid 8 near the interface. In accordance with the flow of the liquid 8 in the vicinity of the interface, a flow also occurs in the liquid 9 in the vicinity of the interface. That is, the liquid 8 can be indirectly driven by using the liquid 8 as the driving liquid.

  According to the present embodiment, in the case where the liquid 9 is altered by flowing electricity, the flow of the liquid 9 is created by indirectly generating a flow in the liquid 8 different from the liquid 9. The effect that it is possible can be acquired. According to the present embodiment, the liquid to be driven can be fed by applying a strong electric field to the driving liquid prepared separately from the liquid to be driven that cannot apply a strong electric field.

(Embodiment 3)
This embodiment is a modification of the second embodiment. Only the characteristic points of the present embodiment will be described below with reference to FIG. FIG. 4 is a schematic cross-sectional view for explaining the jet flow generating device of the present embodiment. The jet generating device of the present embodiment generates a flow in the liquid 10 having a higher specific gravity than the liquid 8 used in the second embodiment. The operation of the jet generating device of this embodiment is the same as that of the second embodiment, and a flow is generated in the liquid 8 and a flow is generated in the liquid 10 indirectly.

(Embodiment 4)
This embodiment is a modification of the second embodiment. Only the characteristic points of the present embodiment will be described below with reference to FIG. FIG. 5 is a schematic cross-sectional view for explaining the jet flow generating device of the present embodiment. As shown in FIG. 5, in order to efficiently transmit the flow of the liquid 8 serving as a driving source to the liquid 9, a wall 11 may be provided to narrow the flow path of the liquid 8. By doing so, the interface is waved by the jet, and the liquid 9 sandwiched between the wave and the wall is carried along with the wave along the wall. According to this embodiment, the flow of the driving liquid and the driven liquid can be further increased by narrowing the flow path, and the liquid feeding efficiency can be increased.

(Embodiment 5)
This embodiment is an application example of the first embodiment. Only the characteristic points of this embodiment will be described below with reference to FIG. The jet flow generating apparatus of the present embodiment is characterized in that it is possible to take out rotational motion from the generated jet flow. FIG. 6 is a schematic cross-sectional view of the jet generating device of the present embodiment. As shown in FIG. 6, the jet generating device of the present embodiment is provided with an impeller 14 having a rotating shaft and a wing that receives the jet. One or more (two in FIG. 6) electrodes 1 covered with the insulator 5 in the jet generating device are installed at positions where the jet impinges on the impeller 14.

  Furthermore, a bubble reservoir 13 for collecting bubbles 7 generated from the electrode 1 of the jet flow device is provided at a position opposite to the gravity direction. The bubble reservoir 13 is provided with heat radiating fins 12 that are liquefaction devices. The heat radiating fins 12 can be configured, for example, by being provided on the wall surface of the bubble reservoir 13. Of course, an active cooler may be installed instead of the radiating fin 12. When the bubbles 7 are electrolyzed gas, a combustion device that returns to the liquid 4 by burning instead of cooling may be installed, or a cooling device and a combustion device may be used in combination. Furthermore, in order to suppress the operating cost of the motor, the amount of the bubbles 7 in the bubble reservoir 13 can be measured, and the liquefying device can be operated only when the bubbles 7 reach a certain amount. The amount of bubbles 7 can be measured, for example, by installing a liquid level meter or an electric resistance meter.

  Next, operation | movement of the jet flow production | generation apparatus of this embodiment is demonstrated. The jet generated from the electrode 1 of the jet generating device hits the blades of the impeller 14 and rotates the impeller 14. Therefore, rotational motion can be obtained from the rotational shaft of the impeller 14. Further, among the bubbles 7 generated from the electrode 1 of the jet flow generating device, the bubbles 7 that remain without being liquefied are subjected to buoyancy, move in the direction opposite to the direction of gravity, and accumulate in the bubble reservoir 13 shown in FIG. When the bubbles 7 in the bubble reservoir 13 are vaporized liquid, the bubbles 7 are cooled by the radiation fins 12 functioning as a liquefier and returned to the liquid 4.

  According to the present embodiment, when the bubbles 7 are scattered in the liquid 4, the bubbles 7 serve as a buffer material and the transmission of the explosive force is weakened and the jet flow is weakened. Therefore, the bubble reservoir 13 is provided at a location away from the jet generation location, and the bubbles 7 are collected there and liquefied, so that the bubbles 7 do not stay in the liquid 4. Thereby, it becomes possible to generate a jet flow continuously. Further, since the generated bubbles 7 receive a force in the direction opposite to the direction of gravity due to buoyancy and move, the bubbles 7 can be efficiently collected by disposing the bubble reservoir 13 on the moving direction side. Moreover, since the radiation fin 12 which is a liquefier is installed in the bubble reservoir 13, the bubble reservoir 13 can have a small capacity.

  Furthermore, according to the present embodiment, it is possible to configure a versatile motor by changing the jet flow into a rotational motion. Since a magnetic field is not required, a motor that is smaller than an electromagnetic motor can be configured. The motor configured using the jet flow generating device of the present embodiment can obtain a strong torque even if it is small in size because it uses a jet flow caused by an explosion. Moreover, even if the applied voltage is constant, the generation of bubbles 7, explosion, and liquid filling process occur continuously, so that it is not necessary to control the power supply voltage in accordance with the growth of bubbles 7.

It is a schematic structure sectional view of the jet flow generating device in a 1st embodiment. (A) is a figure for demonstrating operation | movement of the jet flow production | generation apparatus in 1st Embodiment. (B) is a figure for demonstrating operation | movement of the jet flow production | generation apparatus in 1st Embodiment. (C) is a figure for demonstrating operation | movement of the jet flow production | generation apparatus in 1st Embodiment. It is a schematic sectional drawing for demonstrating the jet flow production | generation apparatus in 2nd Embodiment. It is a schematic sectional drawing for demonstrating the jet flow production | generation apparatus in 3rd Embodiment. It is a schematic sectional drawing for demonstrating the jet flow production | generation apparatus in 4th Embodiment. It is a schematic sectional drawing of the jet flow production | generation apparatus in 5th Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Electrode 2 Electrode 3 Power supply 4 Liquid 5 Insulator 6 Bubble holding part 7 Bubble 8 Liquid 9 Liquid 10 Liquid 11 Wall 12 Radiation fin 13 Bubble storage part 14 Impeller

Claims (13)

A first electrode made of a conductive material arranged in a specific first liquid and having a predetermined portion covered with an insulator; and a second electrode made of a conductive material arranged in the first liquid; And a power source in which the first and second electrodes are connected to different polarities, and a voltage is applied to the first liquid to generate bubbles, thereby generating a jet in the first liquid. A generating device,
In the first electrode, by causing the insulator to protrude from the end portion of the electrode into the first liquid, the bubbles generated by the voltage application are held in the vicinity of the end portion of the first electrode. The first and second electrodes are disposed in the first liquid so as to generate an unequal electric field by applying a voltage from the power source, and are in contact with the liquid in the first electrode. The area is smaller than that of the second electrode and is covered with the bubbles generated by voltage application, and a voltage is applied to the first liquid by the first and second electrodes and the power source. The bubble is generated in the vicinity of the end of the first electrode, the bubble is held in the bubble holding unit, and the held bubble is vaporized explosively to generate a jet in the first liquid. A jet generating device characterized in that   2. The jet generating device according to claim 1, wherein the applied voltage is a voltage such that an electric field strength in the bubble is equal to or higher than a dielectric breakdown electric field of the bubble.   The first liquid of the jet flow generating device and the second liquid having a specific gravity different from that of the liquid are laminated so as to cause a flow in the first liquid near the interface. 3. The flow of the second liquid according to claim 1, wherein the first liquid and the second electrode are arranged, and the flow of the first liquid in the vicinity of the interface causes the flow of the second liquid. Jet generator.   4. The jet generating device according to claim 3, wherein a wall is provided in the second liquid in the vicinity of the interface in order to form a flow path for the second liquid.   One or more jet generating apparatuses according to any one of claims 1 to 4 are provided, and an impeller that rotates by a liquid jet generated from the jet generating apparatus is provided in the first or second liquid. An actuator characterized by that.   6. The actuator according to claim 5, further comprising a bubble reservoir for collecting bubbles generated from the first or second liquid.   The actuator according to claim 6, wherein the bubble reservoir is disposed in a direction opposite to a gravitational direction with reference to the first electrode in which the bubbles are generated.   The actuator according to claim 6 or 7, further comprising a liquefying unit configured to liquefy the bubbles accumulated in the bubble reservoir.   A bubble amount measuring means for measuring the amount of bubbles accumulated in the bubble reservoir is further provided, and the bubbles are liquefied by the liquefying means when the amount of bubbles measured by the means exceeds a predetermined value. The actuator according to claim 8. A first electrode made of a conductive material arranged in a specific first liquid and having a predetermined portion covered with an insulator; and a second electrode made of a conductive material arranged in the first liquid; And a power source in which the first and second electrodes are connected to different polarities, and a voltage is applied to the first liquid to generate bubbles, thereby generating a jet in the first liquid. A jet generating method for a generator,
In the first electrode, by causing the insulator to protrude from the end portion of the electrode into the first liquid, the bubbles generated by the voltage application are held in the vicinity of the end portion of the first electrode. The first and second electrodes are disposed in the first liquid so as to generate an unequal electric field by applying a voltage from the power source, and the first electrode and the second electrode are in contact with each other. The liquid area is smaller than that of the second electrode and is set to a size covered by the bubbles generated by voltage application.
The first and second electrodes and the power source apply a voltage to the first liquid to generate the bubbles in the vicinity of an end of the first electrode;
And a step of generating a jet in the first liquid by the bubble holding unit holding the generated bubble and vaporizing the held bubble explosively. .   The jet generation method according to claim 10, wherein the applied voltage is a voltage such that an electric field strength in the bubble is equal to or higher than a dielectric breakdown electric field of the bubble.   The first liquid of the jet flow generating device and the second liquid having a specific gravity different from that of the liquid are laminated so as to cause a flow in the first liquid near the interface. The step of arranging the first electrode and the second electrode and generating a flow in the second liquid by the flow of the first liquid in the vicinity of the interface is provided. A method for generating a jet according to 1.   13. The jet generating method according to claim 12, wherein a wall is provided in the second liquid in the vicinity of the interface to form a flow path for the second liquid.

Images