CN112880968A - Experimental device for many spark bubbles research in shear flow - Google Patents
Experimental device for many spark bubbles research in shear flow Download PDFInfo
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- CN112880968A CN112880968A CN202110053915.9A CN202110053915A CN112880968A CN 112880968 A CN112880968 A CN 112880968A CN 202110053915 A CN202110053915 A CN 202110053915A CN 112880968 A CN112880968 A CN 112880968A
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- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M10/00—Hydrodynamic testing; Arrangements in or on ship-testing tanks or water tunnels
Abstract
The invention provides an experimental device for researching multiple electric spark bubbles in shear flow, which relates to the field of underwater explosion, and particularly relates to an experimental device for researching multiple electric spark bubbles in shear flow. And a light source and a high-speed camera are arranged on two sides of the bracket and are arranged opposite to the water tank. The invention has safe use and good experimental effect, and can provide an experimental device for the research of underwater explosion bubbles in a shear flow field.
Description
Technical Field
The invention relates to an experimental device for researching multiple spark bubbles in shear flow, and belongs to the field of experimental devices for researching underwater explosion.
Background
The cavitation groups generally exist in practical applications such as ship engineering, hydraulic mechanical engineering, underwater weapon engineering and the like, for example, a large number of cavitation bubbles are formed on blades when a propeller rotates underwater, and cavitation bubbles in different areas are gathered together to form cavitation bubble groups with specific properties, such as bubble cavitation bubble groups, sheet cavitation bubble groups, cloud and mist cavitation bubble groups and the like. Under the action of the flow field environment, the cavitation groups can generate complex collapse phenomena. This phenomenon is considered a very dangerous phenomenon in practical engineering applications. Compared with the existing form of a single vacuole, in the practical application field, the vacuoles are often in the form of clusters, and the moving characteristic of the vacuole clusters is the key for solving the practical problem.
Under practical conditions, the flow field environment where the cavitation is located is often quite complex and is affected by the combination of shear flow field structure (velocity/pressure gradient) and boundary conditions with different object plane characteristics. When moving in a flow field with velocity gradient, the cavitation is acted by lifting force, and the existence of an object plane can also generate force action to induce the cavitation to generate asymmetric jet flow, so that a cavitation collapse mechanism different from a free field is formed.
In addition, because the manufacturing and the use of the initiating explosive devices are strictly controlled by the state, the development of the underwater explosion test of the initiating explosive devices such as explosives and gunpowder is limited, most students do not have the opportunity to develop the test, and the research on the multi-bubble underwater explosion is more difficult.
Therefore, an experimental device which has a shear flow field structure, can be repeatedly used, does not use initiating explosive devices as an explosion source, simultaneously generates a plurality of explosion bubbles and can be used for researching the multiple bubbles in the shear flow of an experiment in a common laboratory is urgently needed.
Disclosure of Invention
The invention aims to provide an experimental device for researching a plurality of electric spark bubbles in a shearing flow field, which is mainly characterized by having a shearing flow field structure, being reusable, not using initiating explosive devices as explosion sources, simultaneously generating a plurality of explosion bubbles and being capable of carrying out experiments in common laboratories.
The purpose of the invention is realized as follows: including setting up high-speed camera, light source, control box, support on the laboratory bench, setting up at the motor at support top, setting up urceolus, inner tube and the inner tube end cover of setting in the urceolus in the support, including the inner tube end cover set up three at least group discharge structure, the rotary rod is connected to the output of motor, and the rotary rod is provided with the rotor plate through swivelling joint spare, high-speed camera, light source symmetry set up in the both sides of support, and after the inner tube was filled with water, at outer section of thick bamboo dress water, and highly surpass the inner tube end cover upper end after the installation of the water of urceolus.
The invention also includes such structural features:
1. each group of discharge structure comprises a positive discharge needle column and a negative discharge needle column, and discharge needles arranged at the lower ends of the discharge needle columns, and the discharge needle columns are connected with the end cover of the inner cylinder.
2. There are three groups of discharge structures.
Compared with the prior art, the invention has the beneficial effects that: the invention adopts high-voltage electrical discharge as an explosion source, and changes the position and the quantity of generated bubbles by adjusting the position and the quantity of the upper cylinder of the end cover of the inner cylinder. The inner cylinder end cover is added on the inner cylinder body, so that the volume of vortex generated by rotation of the rotating rod can be effectively reduced, and the volume of liquid capable of being tested is increased. The position of the holes in the end cover of the inner cylinder can be adjusted, and the number of the holes can be increased and changed according to the experimental requirements, so that the number of the generated bubbles can be changed. Compared with the prior art, the method is more convenient in the aspect of generating multiple bubbles. In the aspect of synchronization of bubbles, the electric wire is not required to be placed in water, and the synchronization is better. In addition, the whole process of underwater electric spark bubbles is observed through a high-speed camera, and the state of the underwater electric spark bubbles can be better compared with that of explosion bubbles in a free field. This patent explodes the source and adopts the electric spark, has avoided the national control to the initiating explosive device, and the laboratory site no longer receives the restriction, and relevant experiment can be carried out in ordinary laboratory. The experimental method is safe to use, good in experimental effect and capable of being repeatedly used for many times, and an effective experimental method can be provided for the mechanism research of a plurality of electric spark bubbles under a shear flow field.
Drawings
FIG. 1 is a partial schematic view of a discharge needle and a discharge needle according to the present invention;
FIG. 2 is a schematic view of the discharge mechanism of the present invention mounted on the end cap of the inner barrel;
FIG. 3 is a schematic view of the connection of the end cap of the inner barrel to the inner barrel according to the present invention;
FIG. 4 is a schematic view of the connection of the rotating parts of the present invention;
FIG. 5 is an overall schematic view of the present invention;
description of the drawings: 1, a discharge needle column; 2, discharging needles; 3 rotating the rod; 4, rotating the sheet; 5 rotating the connecting piece; 6, inner cylinder end cover; 7, an inner cylinder body; 8, an outer cylinder; 9, a motor; 10 mounting a column; 11, mounting a cross beam; 12 light source; 13 a support; 14 a control box; 15 high speed camera.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.
The purpose of the invention is realized as follows: the device comprises a support, an outer barrel arranged on the support, an inner barrel arranged in the outer barrel, an inner barrel end cover matched with the inner barrel, a beam arranged on the upper end face of the support, a mounting column arranged on the beam, a motor fixed on the mounting column, a rotating rod matched with the motor, a rotating connecting piece and a rotating sheet matched with the rotating rod, and a discharge needle column and a discharge needle arranged on the inner barrel end cover. And a light source and a high-speed camera are arranged on two sides of the bracket and are arranged opposite to the water tank. The position of the hole in the end cover of the inner barrel can be defined by user, so that the position of the generated bubbles can be adjusted, and the hole is formed in the bottom of the inner barrel, so that the water in the inner barrel can be conveniently discharged. After the inner cylinder is filled with water, the outer cylinder is filled with water, and the height of the water exceeds the upper end of the end cover of the inner cylinder after installation, so that no bubbles are generated in the inner cylinder. The discharge needle columns are connected to the end cover of the inner cylinder through insulating binding posts, the discharge voltage is controlled through an external control box, and the size of generated bubbles is adjusted; the number of the generated bubbles is changed by increasing the number of the holes and the discharge needle columns, namely, the group number of the discharge structures is adjusted, and meanwhile, the synchronous condition of the generation of the bubbles needs to be noticed.
With the aid of attached drawings 1-5, the shearing device is mainly used for researching multiple spark bubbles in a shearing flow field, and provides an experimental device for researching bubbles in different speed flow fields, different quantities and different distances. The device includes: a discharge needle column 1; a discharge needle 2; a rotating rod 3; a rotary blade 4; a rotating connecting piece 5; an inner cylinder end cover 6; an inner cylinder body 7; an outer cylinder 8; a motor 9; a mounting post 10; mounting the cross beam 11; a light source 12; a bracket 13; a control box 14; a high speed camera 15. The outer cylinder 8 is fixed on the bracket 13, and the inner cylinder body 7 is arranged in the outer cylinder 8 and has the same axle center with the outer cylinder 8; the inner cylinder end cover 6 and the inner cylinder barrel 7 are fixedly connected through bolts; the discharge needle columns 1 and the discharge needles 2 are arranged on the inner cylinder end cover 6 through insulating binding posts, the positions and the number of generated bubbles are changed by adjusting the positions and the number of holes in the inner cylinder end cover 6, and the positions of the holes can be better determined because the inner cylinder end cover 6 is fixed; the rotating rod 3, the rotating connecting piece 4 and the rotating sheet 5 are installed according to a schematic diagram; the installed rotating rod 4 and a hole in the center of the inner cylinder end cover 6 are coaxially installed, and the height from the bottom of the inner cylinder body 7 can be determined by self; the mounting cross beam 11 is mounted on the bracket 13 and is parallel to the upper end surface of the bracket 13; the mounting column 10 is mounted on the mounting cross beam 11; the motor 9 is arranged on the mounting column 10; the motor 9 is connected with the installed rotating column 4 through a rigid coupling, so that the rotating rod 3 is driven, and the water in the inner cylinder 7 is driven to rotate; the inner cylinder 7 is filled with water, the outer cylinder 8 is also filled with water, and the water level exceeds the upper end surface of the installed inner cylinder end cover 6, so that no air bubble which can influence the experiment exists in the water in the inner cylinder 7 for the experiment.
The experimental use environment, the specific structure and the experimental process of the invention are as follows:
1. experiment using environment
The experimental use environment of the invention is shown in the attached figure 5, and besides the device of the invention, the device also comprises: a light source 12, a high-speed camera 15, a control box 14, an experiment table, a data acquisition system and the like.
The outer cylinder 8 is made of an acrylic material, is placed on the support 13 during an experiment, and is fixed, and the high-speed camera 15 is placed on one side of the outer cylinder 8 and is about 0.5 m away from the outer wall of the outer cylinder 8. The light source 12 is arranged on one side opposite to the experimental water tank, the distance between the light source 12 and the outer wall of the outer barrel 8 is about 0.1 m, and the center of the light source is as high as the high-speed camera 15. The experiment table is arranged at a position about 3 meters away from the experiment water tank, and the control box 14 and the data acquisition system are arranged on the experiment table.
2. Concrete structure of experimental device
The outer cylinder 8 is fixed on the bracket 13, and the inner cylinder barrel 7 is arranged in the outer cylinder 8 and has the same axle center with the outer cylinder 8; the inner cylinder end cover 6 and the inner cylinder barrel 7 are fixedly connected through bolts; the discharge needle columns 1 and the discharge needles 2 are arranged on the inner cylinder end cover 6 through insulating binding posts, the positions and the number of generated bubbles are changed by adjusting the positions and the number of holes in the inner cylinder end cover 6, and the positions of the holes can be better determined because the inner cylinder end cover 6 is fixed; the rotating rod 3, the rotating connecting piece 4 and the rotating sheet 5 are installed according to a schematic diagram; the installed rotating rod 4 and a hole in the center of the inner cylinder end cover 6 are coaxially installed, and the height from the bottom of the inner cylinder body 7 can be determined by self; the mounting cross beam 11 is mounted on the bracket 13 and is parallel to the upper end surface of the bracket 13; the mounting column 10 is mounted on the mounting cross beam 11; the motor 9 is arranged on the mounting column 10; the motor 9 is connected with the installed rotating column 4 through a rigid coupling. The discharge needle 2 discharges to cause the water in the inner cylinder body 7 to generate explosion bubbles.
3. Procedure of experiment
The experimental process of the invention is as follows:
(1) and assembling the experimental device according to the experimental content and the concrete structure of the experimental device and by combining the attached drawings 1-5. The experimental environment was arranged according to the experimental use environment as described above and fig. 5.
The light intensity of the light source 12 is adjusted according to the illumination intensity during the experiment. And adjusting the distance between the discharge needle 2 and the inner barrel end cover 6 to be required. The light source 12 and the high-speed camera 15 are adjusted in height to be aligned with the discharge needle 2. Cables such as required data lines, power lines, control lines and the like are connected.
(2) And (4) switching on a power supply, and jointly adjusting each control device, each testing device and each acquisition device to a state to be tested.
(3) And adjusting the discharge voltage of the discharge needle 2 to the required voltage and finishing charging, and placing the experiment trigger controller in a triggerable state.
(4) And triggering a trigger controller, and starting the work of the light source 12, the high-speed camera 15 and the data acquisition equipment. After the delay, the discharge needle discharges to cause explosion in water. The explosion process in the water will be recorded by the high speed camera 15.
In summary, the invention relates to an experimental device for researching multiple spark bubbles in shear flow, which does not use initiating explosive devices as explosion sources, has a shear flow field structure, can be repeatedly used, generates multiple explosion bubbles, has a simple structure, is convenient to operate and obvious in experimental effect, and is an experimental device for multiple bubbles in shear flow, and can be used for carrying out experiments in a common laboratory.
The invention relates to the field of underwater explosion, in particular to an experimental device for researching a plurality of electric spark bubbles in shear flow, which comprises a bracket, an outer cylinder arranged on the bracket, an inner cylinder arranged in the outer cylinder, an inner cylinder end cover matched with the inner cylinder, a cross beam arranged on the upper end surface of the bracket, an installation column arranged on the cross beam, a motor fixed on the installation column, a rotating rod matched with the motor, a rotating connecting piece and a rotating sheet matched with the rotating rod, and a discharge needle column and a discharge needle arranged on the inner cylinder end cover. And a light source and a high-speed camera are arranged on two sides of the bracket and are arranged opposite to the water tank. The invention has safe use and good experimental effect, and can provide an experimental device for the research of underwater explosion bubbles in a shear flow field.
Claims (3)
1. Experimental device for many spark bubbles research in shear flow, its characterized in that: including setting up high-speed camera, light source, control box, support on the laboratory bench, setting up at the motor at support top, setting up urceolus, inner tube and the inner tube end cover of setting in the urceolus in the support, including the inner tube end cover set up three at least group discharge structure, the rotary rod is connected to the output of motor, and the rotary rod is provided with the rotor plate through swivelling joint spare, high-speed camera, light source symmetry set up in the both sides of support, and after the inner tube was filled with water, at outer section of thick bamboo dress water, and highly surpass the inner tube end cover upper end after the installation of the water of urceolus.
2. The experimental apparatus for multi-spark-bubble study in shear flow according to claim 1, characterized in that: each group of discharge structure comprises a positive discharge needle column and a negative discharge needle column, and discharge needles arranged at the lower ends of the discharge needle columns, and the discharge needle columns are connected with the end cover of the inner cylinder.
3. Experimental setup for multi-spark-bubble study in shear flow according to claim 1 or 2, characterized in that: there are three groups of discharge structures.
Priority Applications (1)
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| CN202110053915.9A CN112880968B (en) | 2021-01-15 | 2021-01-15 | Experimental device for research on multi-spark bubbles in shear flow |
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| CN202110053915.9A CN112880968B (en) | 2021-01-15 | 2021-01-15 | Experimental device for research on multi-spark bubbles in shear flow |
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