Helium bubble particle generator and helium bubble manufacturing equipment comprising same

Abstract

The utility model discloses a helium bubble particle generator and helium bubble making equipment comprising the helium bubble particle generator. The helium bubble particle generator comprises a nozzle, and a helium channel, an air channel, a bubble liquid channel and an airflow cavity are formed in the nozzle; the helium source is connected with the helium channel to convey helium; the air source is connected with the air channel to convey air; the bubble liquid source is connected with the bubble liquid channel to convey bubble liquid; and the pressure regulating valve is used for controlling the pressure intensity of the output fluid. The generated helium bubbles are soap bubbles filled with helium, the helium bubbles with neutral buoyancy can be generated by adjusting the proportion of the helium to the bubble liquid, and therefore the good flow following performance is achieved. The particle diameter of helium bubbles generated by the device is millimeter or submillimeter magnitude, light with enough intensity can be scattered, a large number of helium bubble particles can be generated in unit time, and the requirement of large-view-field PIV experimental measurement can be met. The utility model relates to the field of particle image velocity measurement.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of particle image velocimetry, and in particular to a helium bubble particle generator and a helium bubble making device comprising the same. BACKGROUND

[0002] PIV is a measurement technique that obtains fluid velocity field information by illuminating a sequence of images of particles suspended in the fluid. Before conducting a PIV experiment, some small particles or tracers need to be added to the flow field. These particles can be small oil droplets, bubbles, or fluorescent particles excited by a laser beam, etc. The particles are carried by the fluid and exhibit the characteristics of flow. The PIV system uses a laser to illuminate the fluid and focuses the laser beam onto a relatively small point. Since the particles are suspended in the fluid, they will be illuminated by the laser beam and produce scattered light, which is the signal measured by the PIV system. At the same time, a high-speed camera is used to capture a sequence of images of the suspended particles. The captured image sequence usually contains two images, and the time interval between them is usually a few microseconds to a few milliseconds. Then the displacement between the same particles in the two images is determined by correlation analysis, and the velocity vector is calculated according to the known time interval, and finally the specific distribution of the fluid velocity field is obtained.

[0003] As can be seen from the measurement principle of PIV, the distribution of the velocity field needs to be reflected by the tracer particles, so the quality of the PIV image is closely related to the quality of the tracer particles. In order to obtain an accurate velocity field, tracer particles with good followability and imaging visibility are needed. In air flow field, common liquid or solid tracer particles, which can be suspended in air for a long time, usually have a particle diameter of nanometer or micrometer order. However, due to the small particle size of these particles, their scattering light capability is weak, and under the limited light power, the measurable spatial range is usually limited.

[0004] For some low-speed air flow field experiments, it is often necessary to measure the flow field structure in a larger range. Due to the limitation of hardware light power, the scattering light intensity of conventional liquid or solid tracer particles is not enough. In order to obtain satisfactory results, the maximum field of view in PIV measurement needs to be expanded. Therefore, it is an effective way to solve the problem to seek larger particle diameter tracer particles with good flow followability and imaging visibility. CONTENT OF THE INVENTION

[0005] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application proposes a helium bubble particle generator, which can obtain ideal particle images in large field of view PIV testing.

[0006] In addition, the present application also proposes a helium bubble making device comprising the above-mentioned helium bubble particle generator.

[0007] The helium bubble particle generator according to the first aspect of the present application comprises:

[0008] a nozzle, which is internally provided with a helium gas channel, an air channel, a bubble liquid channel and a gas flow cavity, the helium gas channel, the air channel and the bubble liquid channel are all connected to the gas flow cavity, and the gas flow cavity is provided with an output port to discharge helium bubbles;

[0009] a helium gas source connected to the helium gas channel for conveying helium gas to the helium gas channel;

[0010] an air source connected to the air channel for conveying air to the air channel;

[0011] a bubble liquid source connected to the bubble liquid channel for conveying bubble liquid to the bubble liquid channel;

[0012] a pressure regulating valve installed between the helium gas source and the nozzle, between the air source and the nozzle, and between the bubble liquid source and the nozzle, for controlling the pressure of the output fluid.

[0013] The helium bubble particle generator according to the present application has at least the following beneficial effects: the helium bubbles generated by the present application are soap bubbles filled with helium gas inside, the density of helium gas is smaller than that of air, and by adjusting the ratio of helium gas and bubble liquid, helium bubbles with neutral buoyancy can be generated, thereby having good flow following property. The particle diameter of the helium bubbles generated by the present application is in the order of millimeter or sub-millimeter, which can scatter light of sufficient intensity, a large number of helium bubble particles can be generated per unit time, and the requirements of large field PIV experimental measurement can be met.

[0014] According to some embodiments of the present application, the gas flow cavity is in the shape of "U", the air channel is connected to the end of the gas flow cavity, and the helium gas channel and the bubble liquid channel are connected to the middle part of the gas flow cavity.

[0015] According to some embodiments of the present application, the end of the gas flow cavity is provided with a buffer cavity, the inner diameter of the buffer cavity is larger than the middle part of the gas flow cavity, and the air channel is connected to the buffer cavity.

[0016] According to some embodiments of the present application, the helium gas channel and the bubble liquid channel are arranged in parallel and adjacent to each other.

[0017] According to some embodiments of the present application, the helium gas channel and the bubble liquid channel are coaxially arranged, and the helium gas channel is surrounded by the bubble liquid channel.

[0018] According to some embodiments of the present application, the nozzle interior is further provided with a bubble liquid buffer cavity, the bubble liquid buffer cavity is connected with the bubble liquid channel, the bubble liquid source supplies bubble liquid to the bubble liquid buffer cavity, and the bubble liquid enters the bubble liquid channel through the bubble liquid buffer cavity.

[0019] According to some embodiments of the present application, a funnel-shaped structure is arranged at the joint of the bubble liquid buffer cavity and the bubble liquid channel, and the bubble liquid buffer cavity guides the bubble liquid therein to enter the bubble liquid channel.

[0020] According to the second aspect of the embodiments of the present application, the helium bubble manufacturing device comprises a fixing disc and a plurality of helium bubble particle generators, the fixing disc is provided with a plurality of mounting holes, and the nozzle is mounted in the mounting hole.

[0021] According to the helium bubble manufacturing device of the embodiments of the present application, at least the following beneficial effects are achieved: the fixing disc is used to fix the plurality of nozzles, the manufacturing efficiency of the helium bubble is improved, and the demand of large-scale experiments for the helium bubble is met.

[0022] According to some embodiments of the present application, each of the mounting holes is arranged in an array.

[0023] According to some embodiments of the present application, the helium bubble manufacturing device further comprises a helium gas flow equalizer, an air flow equalizer and a bubble liquid flow equalizer; the helium gas flow equalizer is connected with the helium source and is used to supply helium to the helium channel of each nozzle; the air flow equalizer is connected with the air source and is used to supply air to the air channel of each nozzle; and the bubble liquid flow equalizer is connected with the bubble liquid source and is used to supply bubble liquid to the bubble liquid channel of each nozzle.

[0024] Additional aspects and advantages of the present application will be in part apparent and in part pointed out hereinafter. BRIEF DESCRIPTION OF DRAWINGS

[0025] The accompanying drawings are included to provide a further understanding of the technical scheme of the present application, and constitute a part of the specification, and are used together with the embodiments disclosed in the present application to explain the technical scheme of the present application, and do not constitute a limitation on the technical scheme of the present application.

[0026] Figure 1 FIG. 1 is a structural schematic diagram of a helium bubble particle generator according to an embodiment of the present application;

[0027] Figure 2 FIG. 2 is a three-dimensional diagram of a nozzle in the helium bubble particle generator according to an embodiment of the present application;

[0028] Figure 3 FIG. 3 is a sectional view of the nozzle in the helium bubble particle generator according to an embodiment of the present application.

[0029] Figure 4 Figure 1 is a schematic diagram of the installation of the fixed disc and the nozzle in the helium bubble production equipment of the embodiment of the present application;

[0030] Figure 5 Figure 2 is a three-dimensional view of the helium flow straightener in the helium bubble production equipment of the embodiment of the present application;

[0031] Figure 6 Figure 3 is a three-dimensional view of the air flow straightener in the helium bubble production equipment of the embodiment of the present application;

[0032] Figure 7 Figure 4 is a three-dimensional view of the bubble liquid flow straightener in the helium bubble production equipment of the embodiment of the present application.

[0033] The reference signs: 100-nozzle, 110-helium passage, 120-air passage, 130-bubble liquid passage, 140-air flow cavity, 141-buffer cavity, 150-bubble liquid buffer cavity, 200-helium source, 300-air source, 400-bubble liquid source, 500-pressure regulating valve, 600-fixed disc, 610-mounting hole, 700-helium flow straightener, 800-air flow straightener, 900-bubble liquid flow straightener. DETAILED DESCRIPTION

[0034] The embodiments of the present application are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar notations represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary, only for explaining the present application, and cannot be understood as a limitation of the present application.

[0035] In the description of the present application, it is understood that the orientation description, such as the orientation or position relationship indicated by up, down, front, back, left, right, etc. is based on the orientation or position relationship shown in the drawings, only for the convenience of describing the present application and simplifying the description, and is not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0036] In the description of the present application, the meaning of several is more than one, the meaning of multiple is more than two, greater than, less than, more than, etc. is understood as not including the number, above, below, etc. is understood as including the number. If it is described that the first, second is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or the order of indicated technical features.

[0037] In the description of the present application, the words such as arrangement, installation, connection and the like should be understood in a broad sense unless otherwise explicitly limited, and the person skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical solution.

[0038] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in combination with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the exemplary description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0039] PIV is a measurement technique that obtains fluid velocity field information by illuminating a sequence of images of suspended particles in the fluid. Before conducting a PIV experiment, some small particles or tracers need to be added to the flow field. These particles can be small oil droplets, bubbles, or fluorescent particles excited by a laser beam, etc. The particles are carried by the fluid and exhibit the characteristics of flow. The PIV system uses a laser to illuminate the fluid and focuses the laser beam onto a relatively small point. Since the particles are suspended in the fluid, they will be illuminated by the laser beam and produce scattered light, which is the signal measured by the PIV system. At the same time, a high-speed camera is used to capture a sequence of images of the suspended particles. The captured image sequence usually contains two images, and the time interval between them is usually several microseconds to several milliseconds. Then the displacement between the same particles in the two images is determined by correlation analysis, and the velocity vector is calculated according to the known time interval, and finally the specific distribution of the fluid velocity field is obtained.

[0040] As can be seen from the measurement principle of PIV, the distribution of the velocity field needs to be reflected by the tracer particles, so the quality of the PIV image is closely related to the quality of the tracer particles. In order to obtain an accurate velocity field, tracer particles with good followability and imaging visibility are needed. In air flow field, common liquid or solid tracer particles, which can be suspended in air for a long time, usually have a particle diameter of nanometer or micrometer order. However, due to the small particle size of these particles, their scattering light capability is weak, and under limited light power, the measurable spatial range is usually limited.

[0041] For some low-speed air flow field experiments, it is usually necessary to measure a large range of flow field structures. Due to the limitation of hardware light power, the scattering light intensity of conventional liquid or solid tracer particles is not enough. In order to obtain satisfactory results, the maximum field of view of PIV measurement is expanded, and the limited scattering efficiency of the tracer particles is improved. Seeking a tracer particle with a larger particle diameter and good flow following and imaging visibility is an effective way to solve the problem.

[0042] To this end, the application provides a helium bubble particle generator. The helium bubble generated by the helium bubble particle generator is a soap bubble filled with helium gas. The density of helium gas is less than the density of air. By adjusting the ratio of helium gas to bubble liquid, a helium bubble with neutral buoyancy can be generated, thereby having good flow following. The particle diameter of the helium bubble generated by the device is in the order of millimeters or sub-millimeters, which can scatter light of sufficient intensity. A large number of helium bubble particles can be generated per unit time, which can meet the requirements of large field PIV experimental measurement.

[0043] In addition, the application also provides a helium bubble making device comprising the above-mentioned helium bubble particle generator. The plurality of nozzles 100 are fixed by the fixing disc 600, which can improve the production efficiency of the helium bubble and meet the demand for helium bubble in large-scale experiments.

[0044] Reference Figure 1 The helium bubble particle generator in the first aspect of the application comprises a nozzle 100, a helium source 200, an air source 300, a bubble liquid source 400 and a pressure regulating valve 500. The nozzle 100 is the main structure of the helium bubble particle generator, which is used to mix helium, air and bubble liquid and generate helium bubbles to prepare for subsequent PIV experiments. The helium source 200 is used to supply helium, the air source 300 is used to supply air, and the bubble liquid source 400 is used to supply a liquid containing bubbles. The three are connected to the nozzle 100 to mix helium, air and bubble liquid in the nozzle 100. The pressure regulating valve 500 is used to control the output speed of the helium source 200, the air source 300 and the bubble liquid source 400 to the nozzle 100.

[0045] Specifically, referring to Figure 2 and Figure 3 , the inside of the nozzle 100 is provided with a helium passage 110, an air passage 120, a bubble liquid passage 130 and an air flow cavity 140. The helium passage 110, the air passage 120 and the bubble liquid passage 130 are connected to the air flow cavity 140, and the mixing of helium, air and bubble liquid is carried out in the air flow cavity 140. The air flow cavity 140 is provided with an output port to discharge the mixed helium bubble.

[0046] A helium source 200 is connected to the helium channel 110 for delivering helium to the helium channel 110; an air source 300 is connected to the air channel 120 for delivering air to the air channel 120; and a bubble liquid source 400 is connected to the bubble liquid channel 130 for delivering bubble liquid to the bubble liquid channel 130. The output flow rates of the helium source 200, the air source 300 and the bubble liquid source 400 can be adjusted respectively to change the proportion of helium, air and bubble liquid in the helium bubbles.

[0047] A pressure regulating valve 500 is installed between the helium source 200 and the nozzle 100, between the air source 300 and the nozzle 100, and between the bubble liquid source 400 and the nozzle 100, for controlling the pressure of the output fluid.

[0048] Further, the airflow cavity 140 is in a "U" shape, the air channel 120 is connected to the end of the airflow cavity 140, and the helium channel 110 and the bubble liquid channel 130 are connected to the middle of the airflow cavity 140. The air from the air channel 120 enters the end of the airflow cavity 140, and the air also acts as a buffer during the process of flowing in the airflow cavity 140, thereby reducing the disturbance of the air flow to the helium and the bubble liquid.

[0049] Further, the end of the airflow cavity 140 is provided with a buffer cavity 141, the inner diameter of the buffer cavity 141 is larger than the middle of the airflow cavity 140, and the air channel 120 is connected to the buffer cavity 141, so that when the air enters the airflow cavity 140 through the air channel 120, the air enters from the buffer cavity 141 with a larger space, which can alleviate the impact force when the air enters, thereby reducing the influence of the high-pressure air on the mixing of the helium and the bubble liquid in the airflow cavity 140.

[0050] Further, in some embodiments, the helium channel 110 and the bubble liquid channel 130 are arranged in parallel and adjacent to each other, so that the helium and the bubble liquid can be mixed first when they enter the airflow cavity 140, thereby improving the mixing efficiency of the helium and the bubble liquid.

[0051] In other embodiments, the helium channel 110 and the bubble liquid channel 130 are coaxially arranged, the helium channel 110 is surrounded by the bubble liquid channel 130, and the helium and the bubble liquid can be mixed first when they enter the airflow cavity 140, thereby improving the mixing efficiency of the helium and the bubble liquid.

[0052] Further, the nozzle 100 is further provided with a bubble liquid buffer cavity 150, the bubble liquid buffer cavity 150 is connected to the bubble liquid channel 130, the bubble liquid source 400 delivers bubble liquid to the bubble liquid buffer cavity 150, and the bubble liquid enters the bubble liquid channel 130 through the bubble liquid buffer cavity 150. Therefore, the bubble liquid first passes through the buffer of the bubble liquid buffer cavity 150 before entering the bubble liquid channel 130.

[0053] Specifically, the bubble liquid buffer cavity 150 is provided with a funnel-shaped structure at the joint with the bubble liquid channel 130, and the bubble liquid buffer cavity 150 guides the bubble liquid therein to enter the bubble liquid channel 130.

[0054] With reference to Figure 4 , the second aspect of the present application is a helium bubble production device, which comprises a fixing disc 600 and a plurality of helium bubble particle generators. The fixing disc 600 is provided with a plurality of mounting holes 610, and the nozzles 100 are mounted in the mounting holes 610. Thus, the plurality of nozzles 100 are fixed by the fixing disc 600, and the production efficiency of the helium bubbles can be improved by increasing the number of the nozzles 100.

[0055] Further, the mounting holes 610 are arranged in an array, so that the output helium bubbles are uniformly sprayed outward.

[0056] Further, the helium bubble production device further comprises a helium flow equalizer 700 (see Figure 5 ), an air flow equalizer 800 (see Figure 6 ) and a bubble liquid flow equalizer 900 (see Figure 7 ). The helium flow equalizer 700 is connected with the helium source 200 and is used to deliver the helium to the helium channels 110 of the nozzles 100. The air flow equalizer 800 is connected with the air source 300 and is used to deliver the air to the air channels 120 of the nozzles 100. The bubble liquid flow equalizer 900 is connected with the bubble liquid source 400 and is used to deliver the bubble liquid to the bubble liquid channels 130 of the nozzles 100.

[0057] The embodiments of the present application are described in detail above in combination with the drawings, but the present application is not limited to the above embodiments, and various changes can be made within the knowledge of those skilled in the art without departing from the purpose of the present application. In addition, the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

Claims

1. A helium bubble particle generator, characterized in that, include: The nozzle has a helium gas channel, an air channel, a bubble liquid channel and an airflow chamber inside. The helium gas channel, the air channel and the bubble liquid channel are all connected to the airflow chamber. The airflow chamber has an output port to discharge helium bubbles. A helium source, which is connected to the helium channel for supplying helium to the helium channel; An air source connected to the air channel for supplying air to the air channel; A bubble liquid source, which is connected to the bubble liquid channel for supplying bubble liquid to the bubble liquid channel; A pressure regulating valve is installed between the helium source and the nozzle, between the air source and the nozzle, and between the bubble liquid source and the nozzle. The pressure regulating valve is used to control the pressure of the output fluid.

2. The helium bubble particle generator according to claim 1, characterized in that: The airflow cavity is U-shaped, the air channel is connected to the end of the airflow cavity, and the helium channel and the bubble liquid channel are connected to the middle of the airflow cavity.

3. The helium bubble particle generator according to claim 2, characterized in that: A buffer cavity is provided at the end of the airflow cavity, and the inner diameter of the buffer cavity is larger than that of the middle part of the airflow cavity. The air passage is connected to the buffer cavity.

4. The helium bubble particle generator according to claim 2, characterized in that: The helium gas channel and the bubble liquid channel are arranged in parallel and adjacent to each other.

5. The helium bubble particle generator according to claim 2, characterized in that: The helium gas channel and the bubble liquid channel are coaxially arranged, and the helium gas channel is surrounded by the bubble liquid channel.

6. The helium bubble particle generator according to claim 5, characterized in that: The nozzle is also provided with a bubble liquid buffer chamber, which is connected to the bubble liquid channel. The bubble liquid source supplies bubble liquid to the bubble liquid buffer chamber, and the bubble liquid enters the bubble liquid channel through the bubble liquid buffer chamber.

7. The helium bubble particle generator according to claim 6, characterized in that: A funnel-shaped structure is provided at the junction of the bubble liquid buffer chamber and the bubble liquid channel, and the bubble liquid buffer chamber guides the bubble liquid therein into the bubble liquid channel.

8. A helium bubble production device, characterized in that, The device includes a fixed disk and a helium bubble particle generator as described in any one of claims 1 to 7, wherein the fixed disk is provided with a plurality of mounting holes and the nozzle is mounted in the mounting holes.

9. The helium bubble production apparatus according to claim 8, characterized in that: The mounting holes are arranged in an array.

10. The helium bubble production apparatus according to claim 8, characterized in that: The helium bubble production equipment further includes a helium gas equalizer, an air equalizer, and a bubble liquid equalizer; the helium gas equalizer is connected to the helium gas source and is used to deliver helium gas to the helium gas channel of each of the nozzles; the air equalizer is connected to the air source and is used to deliver air to the air channel of each of the nozzles. The bubble liquid equalizer is connected to the bubble liquid source and is used to deliver the bubble liquid to the bubble liquid channels of each of the nozzles.

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