Droplet dynamic response testing device under high-frequency pulsed electric field and use method thereof

Abstract

The invention discloses a liquid drop dynamic response testing device under a high-frequency pulsed electric field and a use method thereof, and belongs to the technical field of liquid drop dynamic monitoring, the liquid drop dynamic response testing device comprises a measuring chamber, an electrode plate assembly, a power supply unit and an image acquisition and processing system, the middle electrode plate is grounded and is called as a low-voltage electrode plate, the rest electrode plates are called as high-voltage electrode plates, the area between the low-voltage electrode plate and the high-voltage electrode plate above the low-voltage electrode plate is an upper electric field area, and the area between the low-voltage electrode plate and the high-voltage electrode plate below the low-voltage electrode plate is a lower electric field area; and the image acquisition and processing system is used for acquiring images of liquid drops in the upper electric field area and the lower electric field area and dynamically analyzing the change process of the liquid drops according to the images. The electrode plates which are horizontally arranged are adopted, high-water-content emulsion and water drops in oil can be tested, and meanwhile, the dynamic deformation characteristics of the liquid drops in a high-frequency pulse electric field can be researched under the condition that the particle size, temperature, pressure and flow field of the liquid drops are controllable.

Description

Technical Field

[0001] The present invention relates to the technical field of droplet dynamic monitoring and also to the technical field of emulsion separation. Specifically, it relates to a droplet dynamic response testing device under a high-frequency pulse electric field. The device uses a variety of intelligent sensors to detect the changes of droplets in the high-frequency pulse electric field, which can be used to optimize demulsification conditions or emulsion stabilization conditions and the characteristics of the oil-water interface under different electric fields. Background Art

[0002] Currently, most oil fields in my country have entered the high-water-cut production phase, with the combined water content of most oil zones reaching as high as 90%. Tertiary oil recovery technologies, such as chemical flooding and polymer flooding, have become effective means of increasing oilfield recovery. However, with the widespread application of tertiary oil recovery technologies, emulsion demulsification has become increasingly difficult. Furthermore, the high water content in the middle and late stages of the process makes it very easy for the emulsion to short-circuit after entering the electric demulsifier, resulting in high energy consumption. To address this issue, Bailes proposed a high-frequency pulse electric field demulsification method, which overcomes the shortcomings of electrochemical dehydration technology and effectively solves the problems of high energy consumption and easy short-circuiting. Currently, a variety of high-frequency pulse dehydration devices and experimental devices for optimizing their operating parameters have been disclosed, but all have shortcomings.

[0003] Some high-frequency pulse dehydration devices, such as CN116750927A, CN107344030A, CN1358824A, and CN112940775A, take into account the synergistic effects of multiple methods, but ignore the impact of key parameters such as temperature and pressure on demulsification. The devices are unable to perform pressure and temperature testing within the equipment, and are unable to control and study the droplet parameters within the electric field.

[0004] Some devices, such as CN108414570, provide an experimental system and method for studying the microscopic characteristics of water droplets in oil under the action of an electric field. These devices can study the microscopic characteristics of droplet migration, deformation, rupture, aggregation, and coalescence under variable and controllable temperature conditions. However, these devices suffer from the following drawbacks: First, the device can only qualitatively study the interfacial properties of droplets, i.e., it can only observe the deformation, rupture, and coalescence of droplets under different temperature or electric field conditions. However, the interfacial tension, a key parameter characterizing the changes in droplet rupture and coalescence, is ignored. As droplet morphology changes, the interfacial tension of the droplet changes accordingly. Therefore, the measurement of interfacial tension can quantitatively characterize the characteristics of droplet deformation, but CN108414570 ignores this parameter. Secondly, when an emulsion is broken using an electric field, the droplet volume changes dynamically. While CN108414570 can dynamically characterize processes such as breakage and coalescence, it cannot dynamically capture the changes in droplets, nor can it clearly determine the changes in parameters such as droplet volume during the droplet change process, which in turn affects the calculation of interfacial tension. Thirdly, the electric field within the device typically has a potential difference, resulting in a difference in voltage between the two plates. During demulsification, this voltage difference drives small droplets to aggregate into larger droplets, thereby achieving sedimentation. However, CN108414570 cannot generate this potential difference. Summary of the Invention

[0005] In order to solve at least one of the above problems, the purpose of the present invention is to provide a droplet dynamic response testing device under a high-frequency pulse electric field, which is used to study the dynamic deformation characteristics of droplets under a high-frequency pulse electric field under controllable conditions of emulsion particle size, temperature, pressure, and flow field.

[0006] In order to achieve the above object, the technical solution provided by the present invention is as follows:

[0007] A device for testing the dynamic response of a droplet under a high-frequency pulse electric field, comprising:

[0008] The measuring chamber is made of light-transmitting material, heat-resistant and pressure-resistant, and is sealed. The measuring chamber is equipped with a temperature and pressure control unit to adjust the temperature and pressure of the fluid in the measuring chamber;

[0009] The three-layer flat-hanging electrode plate assembly located in the measurement room includes three electrode plates arranged horizontally from top to bottom. The electrode plates are parallel to each other. The electrode plate assembly in the middle is grounded and is called the low-voltage electrode plate. The electrode plates on both sides are called high-voltage electrode plates. The area between the low-voltage electrode plate and the high-voltage electrode plate above it is the upper electric field area, and the area between the low-voltage electrode plate and the high-voltage electrode plate below it is the lower electric field area.

[0010] A power supply unit electrically connected to the high-voltage electrode plate, used to form a pulsed electric field in the upper electric field region and the lower electric field region;

[0011] An image acquisition and processing system is used to obtain images of liquid droplets in the upper electric field region and the lower electric field region and dynamically analyze the change process of the liquid droplets based on the images;

[0012] The droplet unit is used to transport fluid into the measurement chamber to form droplets.

[0013] As a specific embodiment of the present invention, the image acquisition and processing system includes:

[0014] An image acquisition device, used for acquiring images of liquid droplets in the upper electric field region and the lower electric field region;

[0015] An information processing system electrically connected to the image acquisition device processes the droplet morphology using the Young-Laplace equation to obtain a shape curve of the droplet and calculates the interfacial tension of the droplet based on the shape curve.

[0016] As a specific embodiment of the present invention, the power supply unit can provide different voltages to the two high-voltage electrode plates, so that the electric field strength in the upper electric field area is greater than the electric field strength of the droplet rupture, and the electric field strength in the lower electric field area is lower than the electric field strength of the droplet rupture.

[0017] As a specific embodiment of the present invention, it also includes:

[0018] a circulation system for promoting horizontal flow of fluid in the upper electric field region and the lower electric field region;

[0019] a flow channel, for connecting the upper electric field region and the lower electric field region;

[0020] Furthermore, it also includes a partition made of insulating material, which is used to enclose the upper electric field area and the lower electric field area into closed spaces respectively; the flow channel is a connecting hole located at one end of the low-voltage electrode plate, and the end of the lower electric field area away from the connecting hole is connected to the measuring chamber, and the circulation system is a circulating pump, which is used to suck the liquid in the upper part of the measuring chamber and send it into the end of the upper electric field area away from the connecting hole.

[0021] As a specific embodiment of the present invention, the emulsion preparation unit is provided with branches to independently transport emulsion droplets to one end of the upper electric field region away from the connecting hole and one end of the lower electric field region close to the connecting hole.

[0022] Furthermore, the end of the lower electric field region, facing away from the communication hole, is connected to the measurement chamber via a polytetrafluoroethylene membrane. A liquid reservoir is also included below and connected to the lower electric field region to collect water from the lower electric field region. The polytetrafluoroethylene membrane separates oil from water, allowing oil to pass through the membrane while intercepting water in the lower electric field region. This prevents the oil from carrying water into the circulation pump. Due to its high density, water will settle and displace the oil in the reservoir, preventing significant accumulation of water in the lower electric field region.

[0023] As a specific embodiment of the present invention, the droplet unit is used to inject water into the measuring chamber, and the measuring chamber stores oil. The water forms water droplets after entering the oil.

[0024] As a specific embodiment of the present invention, the droplet unit is used to prepare the emulsion and send the prepared emulsion into the measuring chamber.

[0025] A method for using the above-mentioned droplet dynamic response testing device under a high-frequency pulse electric field comprises the following steps:

[0026] S1. Add oil to the measuring chamber to immerse the electrode plate assembly, and adjust the temperature and pressure of the measuring chamber to the target value;

[0027] S2. Start the power supply unit to provide the same voltage to the two high-voltage electrode plates so that the electric field strength in the upper and lower electric field regions is equal. Use the droplet unit to deliver equal volumes of liquid into the upper and lower electric field regions to form identical droplets. Use the image acquisition and processing system to measure the dynamic response characteristics of the droplets.

[0028] S3, changing the temperature or pressure, repeating step S2, and measuring the dynamic response characteristics of the droplet at different temperatures or pressures;

[0029] S4. Adjust the power supply unit to provide different voltages to the two high-voltage electrode plates so that the electric field strength in the upper electric field region is greater than the electric field strength for droplet rupture, and the electric field strength in the lower electric field region is lower than the electric field strength for droplet rupture. Start the circulation pump to promote the flow of fluid in the electric field region, and feed the fluid into the upper electric field region through the droplet unit. Measure the dynamic response characteristics of the droplets through the image acquisition and processing system. When the droplets in the upper electric field region enter the lower electric field region, feed the fluid into the lower electric field region through the droplet unit, thereby simulating the dynamic response characteristics of droplets of different sizes.

[0030] S5. Change the temperature or pressure, repeat step S4, and measure the dynamic response characteristics of droplets of different sizes under different temperatures or pressures.

[0031] At least one embodiment of the present invention has the following beneficial effects:

[0032] The droplet dynamic response testing device under high-frequency pulse electric field of the present invention can study the dynamic deformation characteristics of droplets under high-frequency pulse electric field under the conditions that the droplet particle size, temperature, pressure and flow field are controllable.

[0033] The present invention adopts horizontally arranged electrode plates, which avoids water droplets connecting into chains to connect high and low voltage electrode plates and cause short circuits, and can test droplets with high water content (such as emulsions).

[0034] When the upper and lower electric fields are set to different intensities, the present invention can use the upper electric field area to generate droplets of smaller particle size, thereby simulating the aggregation and movement characteristics of droplets of different sizes in the lower electric field area, and for the first time simulated the dehydration of different crude oil mixtures. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present invention;

[0036] Figure 2 This is a schematic diagram of the overall structure of another embodiment of the present invention;

[0037] Figure 3 This is a schematic diagram of the overall structure of another embodiment of the present invention;

[0038] In the figure, there is a measuring chamber 100; a low-voltage electrode plate 210; a connecting hole 211; a high-voltage electrode plate 220; a high-voltage output device 310; a transformer 320; a waveform converter 330; an image acquisition device 410; an information processing system 420; a storage tank 510; a homogenizer 520; an injection pump 530; a storage chamber 540; a borescope 550; a partition 610; a circulation pump 620; a polytetrafluoroethylene membrane 630, and a liquid storage tank 640. DETAILED DESCRIPTION

[0039] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0040] Please refer to Figures 1 and 2, which shows the structures of various specific embodiments of the droplet dynamic response test device under high-frequency pulse electric field of the present invention. The droplet dynamic response test device under high-frequency pulse electric field of the present invention includes a measuring chamber 100, an electrode plate assembly (210, 220), a power supply unit (310, 320, 330), an image acquisition and processing system (410, 420) and a droplet unit (510, 520, 530, 540, 550), wherein the measuring chamber 100 is a closed chamber to accommodate fluid, and the measuring chamber 100 is made of a light-transmitting material as a whole to facilitate intuitive observation of changes in the internal emulsion droplets. At the same time, the measuring chamber 100 is equipped with a temperature and pressure control unit for adjusting the temperature and pressure of the fluid in the measuring chamber 100, so as to simulate the dynamic characteristics of the emulsion droplets under different temperature and pressure conditions, thereby determining the influence of temperature and pressure on the emulsion characteristics; the electrode plate assembly (210, 220) is arranged in the measuring chamber 100, which includes three horizontally arranged from top to bottom. The electrode plates are parallel to each other, the electrode plate assembly in the middle is grounded, and is called the low-voltage electrode plate 210, and the electrode plates on both sides are connected to the power supply unit (310, 320, 330), and are called the high-voltage electrode plate 220. The area between the low-voltage electrode plate 210 and the high-voltage electrode plate 220 above it is called the upper electric field area 201, and the area between the low-voltage electrode plate 210 and the high-voltage electrode plate 220 below it is called the lower electric field area 202; the power supply unit (310, 320, 330) is electrically connected to the high-voltage electrode plate 220, and is used to form a pulse electric field in the upper electric field area 201 and the lower electric field area 202; the image acquisition and processing system (410, 420) is used to obtain the droplet image in the upper electric field area 201 and the lower electric field area 202 and dynamically analyze the change process of the droplet according to the image; the droplet unit is used to transport fluid into the measuring chamber to form droplets.

[0041] The emulsion preparation units (510, 520, 530, 540, 550) are used to prepare emulsion and deliver the prepared emulsion to the measurement chamber 100. During the experiment, emulsion droplets are first prepared by the emulsion preparation units (510, 520, 530, 540, 550), and then the droplet units are used to deliver fluid to the measurement chamber to form droplets. After the droplets enter the electric field area of the measurement chamber 100, the image acquisition and processing systems (410, 420) collect and analyze the morphological changes of the droplets.

[0042] In the present invention, the image acquisition and processing system (410, 420) can adopt an existing system, which generally includes an image acquisition device 410 and an information processing system 420. The image acquisition device 410 can adopt a high-speed camera, and the information processing system 420 can adopt a computer. The two are electrically connected. The surface area and droplet shape of the droplet in the electric field can be dynamically captured and recorded by the image acquisition device 410, and transmitted to the droplet shape information processing system 420 to record the shape of the droplet in the measuring chamber 100 in real time. Then, the Young-Laplace equation is used for fitting in the information processing system 420 to obtain the droplet shape curve, and then the interfacial tension of the droplet is obtained. By calculating the interfacial tension of the droplet at different times, the change process of the droplet interfacial tension can be determined.

[0043] In the present invention, the power supply unit (310, 320, 330) can adopt existing equipment. For example, in some embodiments, the power supply unit (310, 320, 330) is composed of a high-voltage output device 310, a transformer 320, and a waveform converter 330 connected in sequence through a high-voltage cable. The high-voltage output device 310 is responsible for providing the required voltage for the system, the transformer 320 is responsible for adjusting the electric field strength of the device, and the waveform converter 330 is responsible for changing the waveform, duty cycle and electric field strength of the electric field, and can output DC, AC and pulse current.

[0044] In existing experimental devices, the electrode plates are often arranged vertically, the liquid flows between the electrode plates, and the separated water settles directly downward. The influence of the electric field direction on the movement of the droplets can be directly quantified by the horizontal movement distance of the droplets. However, as the droplets coalesce and the oil and water separate, the water content in the fluid in the electric field gradually increases from top to bottom, and it is easy to form a water chain in the lower area of the electric field to directly connect the high-voltage electrode plate 220 and the low-voltage electrode plate 210, which will cause a short circuit between the electrode plates. Therefore, it is difficult to simulate high-water-content emulsion droplets. In this regard, in the present invention, each electrode plate is arranged horizontally to avoid the formation of a water chain that directly connects the high-voltage electrode plate 220 and the low-voltage electrode plate 210, so it can be suitable for the simulation of high-water content emulsions. However, after the electrode plates are arranged horizontally, the gravity direction of the droplets and the direction of the electric field are both in the vertical direction, and it is difficult to determine the influence of the electric field direction on the movement of the droplets. Therefore, in some embodiments, the power supply unit (310, 320, 330) provides the same voltage to the two high-voltage electrode plates 220. In this way, the electric field strengths of the upper electric field region 201 and the lower electric field region 202 are the same and the directions are opposite, which can simulate the droplet movement process under different electric field direction conditions, thereby determining the influence of the electric field direction on the droplet movement.

[0045] In some embodiments, the power supply unit (310, 320, 330) provides different voltages to the two high-voltage electrode plates 220 so that the upper electric field region 201 and the lower electric field region 202 are at different electric field strengths. The electric field strength of the upper electric field region 201 is greater than the electric field strength for droplet rupture, so that the droplets rupture in this space, thereby generating droplets of smaller particle size for testing, and no longer needing to prepare droplets of smaller particle size through the droplet unit. The electric field strength of the lower electric field region 202 is set according to the electric field strength of normal dehydration, so that the droplets are aggregated here to form droplets of larger particle size, and finally achieve oil-water separation. In some embodiments, a through hole can be opened on the low-voltage electrode plate 210 in the middle position, so that the small-particle droplets generated in the upper electric field region 201 can enter the lower electric field region 202 through these through holes for further aggregation. In some embodiments, a circulation system can be set up to push the fluid to move horizontally along the electric field area, and then the fluid in the upper electric field area 201 is introduced into the lower electric field area 202 through the flow channel. In this way, the residence time of the fluid in the upper electric field area 201 and the lower electric field area 202 can be increased, which facilitates better adjustment of parameters to obtain droplets of ideal size. There are many specific circulation systems. For example, in some embodiments, Figure 2As shown, a partition 610 made of insulating material is used to enclose the upper electric field region 201 and the lower electric field region 202 into a closed space respectively, and a connecting hole 211 is provided at one end of the low-voltage electrode plate 210, thereby connecting the upper electric field region 201 and the lower electric field region 202; the end of the lower electric field region 202 away from the connecting hole is connected to the measuring chamber 100, that is, the partition 610 connecting the low-voltage electrode plate 210 and the high-voltage electrode plate 220 at this position is removed, and a circulating pump 620 is set to circulate the liquid (mainly After being sucked out, the liquid (for oil) is sent into the upper electric field region 201 at the end away from the connecting hole. In this way, the liquid in the upper part of the measuring chamber 100 can be used to push the fluid in the upper electric field region 201 to move horizontally to the right, and then pass through the connecting hole 211 on the right side of the upper electric field region 201 to enter the lower electric field region 202, and then move horizontally from right to left in the lower upper electric field region 202, thereby changing the size of the droplets entering the lower electric field and simulating the electric field response characteristics of droplets of the same size, which corresponds to the dehydration of crude oil from a single source. Alternatively, droplet units (510, 520, 530, 540, and 550) can be used to deliver droplets to the end of the upper electric field region 201 facing away from the connecting hole and to the end of the lower electric field region 202 near the connecting hole. The upper electric field region can be used to change the size of the droplets, causing them to mix with droplets of different sizes in the lower electric field region 202 and then undergo electrical demulsification, thereby simulating the electric field response characteristics of droplets of different sizes (e.g., 10 μm and 4 μm droplets), which corresponds to the dehydration of various types of water-containing crude oils. Furthermore, in some embodiments, the end of the lower electric field region 202 facing away from the connecting hole is connected to the interior of the measurement chamber 100 via a polytetrafluoroethylene membrane 630. The device also includes a liquid reservoir 640 located below and connected to the lower electric field region 202 for collecting water in the lower electric field region 202. The function of the polytetrafluoroethylene membrane 630 is to separate oil and water. It allows oil to pass through the polytetrafluoroethylene membrane 630 and intercepts water in the lower electric field area 202, thereby preventing the oil from carrying water into the circulation pump 620. Due to the high density of water, it will settle and replace the oil in the liquid storage tank 640, avoiding the accumulation of large amounts of water in the lower electric field area 202.

[0046] The droplet unit of the present invention is used to transport fluid into the measuring chamber to form droplets. In some embodiments, the droplet unit is used to inject water into the measuring chamber 100, which stores oil. The water enters the oil and forms water droplets. In other embodiments, the droplet unit is used to prepare an emulsion and transport the prepared emulsion into the measuring chamber, such as Figure 1-3As shown, the emulsion preparation unit (510, 520, 530, 540, 550) includes a storage tank 510, a homogenizer 520 and an injection pump 530, wherein the homogenizer 520 is used to perform shearing on the liquid in the storage tank 510 to form emulsion droplets, the inlet of the injection pump 530 is connected to the bottom of the storage tank 510, and the outlet is connected to the test chamber, thereby delivering the emulsion droplets into the test chamber. In addition, the injection pump 530 adopts a metering pump, so that the injection volume can be accurately controlled to inject the required volume of fluid into the plate gap.

[0047] In some embodiments, the speed of the homogenizer 520 can be adjusted, thereby controlling the particle size of the emulsion by adjusting the speed of the homogenizer 520. The higher the speed, the smaller the particle size. In addition, a storage chamber 540 and a borescope 550 are provided between the storage tank 510 and the injection pump 530. The storage chamber 540 is used to temporarily store droplets of a certain particle size so that the homogenizer 520 in the storage tank 510 can continue to work to prepare another emulsion of a different particle size, that is, to prepare the emulsion required for the next test. The borescope 550 is equipped with a microscope for observing the particle size of the emulsion. In this way, the homogenizer 520 can operate continuously (without power outage) to prepare emulsion droplets of different particle sizes, thereby quickly studying the effect of shear on the particle size of the emulsion droplets, that is, determining the emulsion particle size corresponding to different shear effects. In some embodiments, the storage tank 510 is also provided with a temperature control unit for studying the effect of temperature on the particle size of the prepared emulsion. At the same time, the temperature of the emulsion droplets can be adjusted to be the same as that of the measuring chamber 100, thereby avoiding drastic changes in the emulsion after entering the measuring chamber 100.

[0048] The temperature and pressure control unit equipped with the measurement chamber 100 in the present invention can be implemented using existing technologies. For example, a temperature sensor can be provided to detect the temperature within the measurement chamber 100, a heater can be provided to heat the fluid, and a controller can be provided to collect temperature data from the temperature sensor and control the heater's heat load accordingly, thereby achieving closed-loop control of the temperature within the measurement chamber 100. For pressure control, a certain volume of gaseous space (directly connected to the liquid phase) can be reserved at the top of the measurement chamber 100, a pressure sensor can be provided to detect the pressure in this gaseous space, a gas injection and discharge device can be provided to increase or decrease the gas volume within this gaseous space, and a controller can be provided to collect data from the pressure sensor and control the operation of the gas injection and discharge device accordingly, thereby achieving closed-loop pressure control.

[0049] In addition, the measurement chamber 100 is provided with a material port for adding materials such as demulsifiers and oils into the test chamber. Of course, this material port can also serve as a drain port to discharge materials after the experiment. In some embodiments, the distance between the electrode plates can be adjusted as needed. In some embodiments, a mobile light source 26 is also provided to provide light for the measurement chamber 25.

[0050] As described above, the test device for droplet dynamic response under high frequency pulse electric field of the present invention can perform various types of tests as needed, including some tests that can be achieved by existing devices. Figure 2 The device shown is taken as an example to illustrate some special testing processes of the present invention.

[0051] A method for using a device for testing the dynamic response of a droplet under a high-frequency pulse electric field comprises the following steps:

[0052] S1. Add oil to the measuring chamber to immerse the electrode plate assembly, adjust the temperature and pressure of the measuring chamber to the target value, and start the emulsion preparation unit to prepare emulsion droplets (for example, using raw materials with an oil-water ratio of 7:3);

[0053] S2. Start the power supply unit to provide the same voltage to the two high-voltage electrode plates so that the electric field strength in the upper and lower electric field regions is equal. Emulsion preparation units are used to deliver equal volumes of emulsion to the upper and lower electric field regions. The dynamic response characteristics of the emulsion droplets are measured using an image acquisition and processing system.

[0054] S3 changes the temperature or pressure, repeats step S2, and measures the dynamic response characteristics of the emulsion droplets at different temperatures or pressures;

[0055] S4. Adjusting the power supply unit to provide different voltages to the two high-voltage electrode plates so that the electric field intensity in the upper electric field region is greater than the electric field intensity for emulsion rupture and the electric field intensity in the lower electric field region is lower than the electric field intensity for emulsion rupture, starting the circulation pump to promote the flow of fluid in the electric field region, feeding emulsion into the upper electric field region through the emulsion preparation unit, measuring the dynamic response characteristics of emulsion droplets through the image acquisition and processing system, and feeding emulsion into the lower electric field region through the emulsion preparation unit when the emulsion in the upper electric field region enters the lower electric field region, thereby simulating the dynamic response characteristics of emulsion droplets of different sizes;

[0056] S5. Change the temperature or pressure, repeat step S4, and measure the dynamic response characteristics of emulsion droplets of different sizes under different temperatures or pressures.

[0057] Those skilled in the art can make various other corresponding changes and deformations based on the technical solutions and concepts described above, and all of these changes and deformations should fall within the scope of protection of the claims of the present invention.

Claims

1. A device for testing the dynamic response of droplets under a high-frequency pulse electric field, characterized in that: include: A sealed measuring chamber made of light-transmitting material, resistant to heat and pressure, equipped with a temperature and pressure control unit for regulating the temperature and pressure of the fluid in the measuring chamber; A three-layer flat-hanging electrode plate assembly located in the measurement chamber, wherein the electrode plate assembly includes three electrode plates arranged horizontally from top to bottom, each electrode plate is parallel to each other, the electrode plate assembly located in the middle is grounded, and is called a low-voltage electrode plate, and the electrode plates located on both sides are called high-voltage electrode plates, wherein the area between the low-voltage electrode plate and the high-voltage electrode plate above it is the upper electric field area, and the area between the low-voltage electrode plate and the high-voltage electrode plate below it is the lower electric field area; a power supply unit electrically connected to the high-voltage electrode plate, configured to form a pulsed electric field in the upper electric field region and the lower electric field region; An image acquisition and processing system, configured to acquire images of the liquid droplets in the upper electric field region and the lower electric field region and dynamically analyze the change process of the liquid droplets based on the images; The droplet unit is used to transport fluid into the measurement chamber to form droplets.

2. The device for testing the dynamic response of a droplet under a high-frequency pulse electric field according to claim 1, characterized in that: The image acquisition and processing system comprises: An image acquisition device, configured to acquire images of the emulsion droplets in the upper electric field region and the lower electric field region; An information processing system electrically connected to the image acquisition device processes the droplet morphology using the Young-Laplace equation to obtain the droplet shape curve, and calculates the interfacial tension of the droplet based on the shape curve.

3. The device for testing the dynamic response of a droplet under a high-frequency pulse electric field according to claim 1, characterized in that: The power supply unit can provide different voltages to the two high-voltage electrode plates, so that the electric field strength of the upper electric field area is greater than the electric field strength of the droplet rupture, and the electric field strength of the lower electric field area is lower than the electric field strength of the droplet rupture.

4. The device for testing the dynamic response of a droplet under a high-frequency pulse electric field according to claim 1, characterized in that: Also includes: a circulation system, used to promote horizontal flow of fluid in the upper electric field region and the lower electric field region; A flow channel is used to connect the upper electric field region and the lower electric field region.

5. The device for testing the dynamic response of a droplet under a high-frequency pulse electric field according to claim 1, characterized in that: It also includes a partition made of insulating material, which is used to enclose the upper electric field region and the lower electric field region into closed spaces respectively; the flow channel is a connecting hole located at one end of the low-voltage electrode plate, and the end of the lower electric field region away from the connecting hole is connected to the measuring chamber, and the circulation system is a circulation pump, which is used to suck the liquid in the upper part of the measuring chamber and send it into the end of the upper electric field region away from the connecting hole.

6. The device for testing the dynamic response of a droplet under a high-frequency pulse electric field according to claim 1, characterized in that: The droplet unit is provided with branches to independently transport droplets to an end of the upper electric field region away from the communicating hole and an end of the lower electric field region close to the communicating hole.

7. The device for testing the dynamic response of a droplet under a high-frequency pulse electric field according to claim 1, characterized in that: The end of the lower electric field region away from the communicating hole is connected to the measuring chamber through a polytetrafluoroethylene membrane; it also includes a liquid storage tank located below the lower electric field region and connected to the lower electric field region, which is used to collect water in the lower electric field region.

8. The device for testing the dynamic response of a droplet under a high-frequency pulse electric field according to claim 1, characterized in that: The droplet unit is used to prepare the emulsion and deliver the prepared emulsion into the measuring chamber.

9. A method for using the above-mentioned droplet dynamic response testing device under high-frequency pulse electric field, comprising the following steps: S1. Add oil into the measuring chamber to immerse the electrode plate assembly, and adjust the temperature and pressure of the measuring chamber to target values; S2. Starting the power supply unit to provide the same voltage to the two high-voltage electrode plates so that the electric field strengths in the upper electric field region and the lower electric field region are equal, respectively delivering equal volumes of fluid to the upper electric field region and the lower electric field region through the droplet unit, and measuring the dynamic response characteristics of the droplet through the image acquisition and processing system; S3, changing the temperature or pressure, repeating step S2, and measuring the dynamic response characteristics of the droplet at different temperatures or pressures; S4. Adjust the power supply unit to provide different voltages to the two high-voltage electrode plates, so that the electric field strength in the upper electric field region is greater than the electric field strength for droplet rupture, and the electric field strength in the lower electric field region is lower than the electric field strength for droplet rupture, start the circulation pump to promote the flow of fluid in the electric field region, feed the emulsion into the upper electric field region through the droplet unit, measure the dynamic response characteristics of the droplets through the image acquisition and processing system, and when the emulsion in the upper electric field region enters the lower electric field region, feed the droplets into the lower electric field region through the droplet unit, thereby simulating the dynamic response characteristics of droplets of different sizes under different electric field intensities; S5. Change the temperature or pressure, repeat step S4, and measure the dynamic response characteristics of emulsion droplets of different sizes under the coupled temperature or pressure.

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