Device and method suitable for visual experiment of smoke line flow field
Technical Field
The invention belongs to the technical field of wind tunnel tests, and particularly relates to a device and a method for a visual experiment of a smoke line flow field.
Background
Flow state observation methods in wind tunnel experiments are roughly classified into two types: the first is a tracing method and the second is an optical method. In the tracing method, a smoke line flow field visualization method is adopted, metal wires are used for heating, smoke oil is vaporized to generate smoke, the flow condition of gas around an aircraft or an object is visually simulated through the smoke, and the collection and analysis of wind tunnel test data are facilitated. A common smoke line flow field visualization method is that a metal wire is vertically stretched to perform a smoke line experiment at a wind tunnel mouth close to the front edge of a model, the flow field structure in a certain distance range can be observed in the mode, but due to the limitation of the smoke line, the smoke effect in the middle and rear parts of the model is not obvious, and therefore, the metal wire needs to be transversely placed close to a region to be measured to smoke in order to obtain the obvious smoke line flow field structure of the local region. In addition, the conventional oil of giving off smoke scribbles for manual, or utilizes gravity to let the oil of giving off smoke flow down along the wire, if for transversely placing the wire, this kind of fat liquoring mode that relies on gravity is unreal, if rely on manual fat liquoring, fat liquoring brush can produce very big interference to the flow field, influences the accuracy of experiment. Aiming at the problems, the device and the method suitable for the smoke line flow field visualization experiment of the transversely arranged metal wires are designed. The device and the method can ensure the accuracy of the test result and improve the test efficiency, which is a technical problem to be solved urgently by technical personnel in the field.
Disclosure of Invention
The invention aims to provide a device and a method suitable for a visual experiment of a smoke line flow field, the method can conveniently and quickly arrange the metal wire near the area to be tested in a transverse mode, and the smoke line experiment result has high reliability.
In order to achieve the purpose, the invention adopts the following technical scheme:
the utility model provides a device suitable for visual experiment of gas line flow field which characterized in that, includes two the same wire conveyor of relative installation, wherein among the wire conveyor: the bottom of the rotating motor (3) is provided with a bolt hole, and the rotating motor (3) can be fixed in the device through the bolt hole and does not move; a bearing of the rotating motor (3) is provided with a buckle, and the spool (2) is fixed on the rotating motor (3) through the buckle after being sleeved on the bearing of the rotating motor (3); the rotating motor (3) rotates under the control of the power supply controller (8) and also drives the spool (2) to rotate along with the rotating motor; the coil of one end of the metal wire is wound on the bobbin (2), the coil of the other end of the metal wire is wound in the other metal wire conveying device in the same mode, and when the rotating motors (3) in the two metal wire conveying devices work in different rotating directions, the metal wire of one bobbin (2) is in a wire winding state and the metal wire of the other bobbin is in a wire unwinding state.
Furthermore, the metal wire (4) is driven in the metal wire conveying device (1) along the conveying chute (11), the roller (7) is arranged in the conveying chute (11), and the roller can play a role in promoting and guiding in the metal wire conveying process. In addition, a metal guide roller (5) is designed at the outlet of the sliding chute, and when the metal guide roller (5) is electrified, the metal wire (4) which is tightly attached to the metal guide roller (5) for transmission can conduct electricity indirectly to generate heat.
Furthermore, the metal wire (4) passes through an oil tank (6) before passing through the metal guide roller (5), small holes are formed at two ends of the oil tank (6), and the metal wire (6) can pass through the small holes. Because the required smoke oil of experimental smoke is equipped with in oil tank (6), after wire (4) passed oil tank (6), the surface of wire (4) can be stained with the smoke oil, and after wire (4) circular telegram in the middle of two devices was heated, the last smoke oil of wire (4) can be heated and vaporize for smog, and under the irradiation of sheet light laser, these smog can be fine as the tracer particle display flow field.
An experimental method based on the experimental device suitable for the visualization of the smoke line flow field is characterized in that: the method comprises the following steps:
the first step is as follows: designing a metal wire conveying device:
the metal wire is conveyed between the two devices mainly by a rotating motor (3) in the conveying device, and the rotating motor (3) is fixed in the middle of the whole conveying device through bolts and is connected and controlled by a power supply controller (8). The power supply controller (8) is provided with a control switch (9) and a rotating speed knob (12), the bearing of the rotating motor (3) is sleeved by the bobbin (2), the bobbin and the bearing are fixed through a buckle at the joint of the bearing and do not move relatively, and when the rotating motor (3) rotates, the bobbin (2) can also rotate at the same rotating speed.
One end of the metal wire (4) needs to be fixedly wound on the spool (2), when the rotating motor rotates, the metal wire (4) wound on the spool (2) can be tightened or loosened along with the rotating motor, and the other end of the metal wire (4) can move in the conveying chute (11). Wherein, be equipped with gyro wheel (7) in the transport spout, the wire is at the transmission in-process, and the gyro wheel can play the effect of promotion and direction. When the metal wire is about to pass through the chute outlet, the metal wire can contact the metal guide roller (5), the position of the metal guide roller (5) in the chute is slightly higher than that of the roller (7), so that the metal wire (4) is attached to the metal guide roller (5) for transmission, and when the metal wire is connected with a metal rod at one end of the metal guide roller (5), the metal wire attached to the metal guide roller (5) can be electrified. In addition, before metal guide roller (5) is being driven to, need pass the oil tank that contains the oil of giving out smoke, oil tank (6) top design has a infundibulate inlet port (10), and after metal wire (4) passed from the aperture at oil tank (6) both ends, can be stained with the oil of giving out smoke on the metal wire surface, the oil of giving out smoke can vaporize for smog after the metal wire ohmic heating.
The second step is that: installation of the device in a wind tunnel:
the two conveying devices (1) are respectively arranged on the outer sides of end plates at two ends of the wing profile, conveying outlets of the two devices are oppositely arranged, and the two conveying outlets are positioned at the same height. After the positions of the two metal wire conveying devices (1) on the end plates are determined, the two metal wire conveying devices (1) are connected with the end plates at the two ends of the wing shape through bolts, two small holes for conveying and moving the metal wires are formed in the positions of metal wire conveying outlets corresponding to the two end plates, and positive and negative wires (13) of a power supply are connected to metal guide rollers (5) in the two devices respectively. When the airfoil model rotates at different attack angles, the conveying device (1) also rotates along with the airfoil model, and the metal wires are still parallel to the spanwise direction of the airfoil.
The third step: installation and debugging of each device before wind tunnel experiment
After the conveying device is installed, a metal wire (4) is additionally arranged in the conveying device (1), one end of the metal wire is fixed and wound on a spool (2) in one device, in order to ensure that the transmission time of the metal wire is enough, the metal wire is wound on the spool (2) as much as possible, the other end of the metal wire is transmitted to the other device through a conveying chute (11) and is fixedly wound on the spool (2) through a chute in the other device. After the metal wires are installed, the power controllers (8) of the two devices are opened, the rotating motors (3) are adjusted, the rotating directions of the two rotating motors are opposite, namely the metal wires of one spool (2) are in a wire winding state and the other spool is in a wire unwinding state, then the rotating speed of the rotating motors (3) is adjusted, the rotating speeds of the two rotating motors can be matched with each other, the transmission speed of the metal wires is proper, and the metal wires are always in a tensioned state in the transmission process.
The main advantages of the invention are:
1) the design idea of the invention is to design a metal wire conveying device to ensure that the surface of the metal wire crossing the airfoil end can emit smoke all the time and the smoke required by the experiment can be vaporized continuously near the area to be tested so as to meet the requirements of a flow field on visualization. The method can not only overcome the difficulty of oiling the transversely arranged metal wires, but also solve the problem of limitation of the measuring position of the longitudinally arranged metal wires.
2) The device meets the automatic transmission of the metal wire, manual oil coating is not needed, the design idea that smoke is emitted in the area to be tested is achieved all the time, the designed device is not complex, used components can be conveniently obtained, the cost of test materials is greatly saved, the designed mechanism cannot influence the test flow field, and the accuracy of the flow field to be tested is guaranteed.
Drawings
FIG. 1 is an overall configuration diagram of a transport apparatus
FIG. 2 is a rear view of the conveyor
FIG. 3 is a schematic view of the overall installation of the device in a wind tunnel
In the drawings:
1. conveying device
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2. Bobbin
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3. Rotating electric machine
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4. Metal wire
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5. Metal guide roller
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6. Oil tank
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7. Roller wheel
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8. Power supply controller
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9. Control switch
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10. Oil inlet funnel
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11. Conveying chute
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12. Rotating speed knob
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13. Power supply wire
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14. Wing model
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15. Camera with a camera module
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16. Laser device
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17. Airfoil end plate
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18. Direct current power supply |
Detailed Description
The invention is further illustrated with reference to the figures and examples.
The method for the visual experiment of the smoke line flow field is characterized in that a set of device suitable for the visual experiment of the smoke line flow field is designed, and the device has the following specific structure:
the device suitable for the flue gas flow field visualization experiment comprises two conveying devices (1) which are positioned at two ends of an airfoil (14), as shown in figures 1 and 2. The wire feeding device comprises a conveying device (1), a transmission power control part and a transmission structure part, wherein the transmission power control part is used for driving a wire shaft (2) to rotate by a rotating motor (3) to complete the transmission process of a metal wire, and a switch and a knob on a power supply controller are used for controlling and adjusting the working state of the rotating motor. The transmission structure part consists of a conveying chute (11) for assisting the transmission of the metal wire, a roller for assisting the movement of the metal wire, a metal guide roller (5) capable of conducting the metal wire and an oil tank (6) for containing the smoke oil.
The invention provides a device for a visual experiment of a smoke line flow field, which has the following action relationship of the structures:
in the conveying device (1), as shown in fig. 1 and 2: the rotating motor (3) is fixed in the middle of the whole conveying device through bolts and is connected and controlled with the power controller (8) through a lead, and the power controller (8) is provided with a red control switch (9), a yellow control switch (9) and a rotating speed knob (12) to control the working state of the rotating motor. The spool (2) is sleeved on the rotating motor (3), the spool (2) and the rotating motor (3) can be locked and fixed through the buckle, and when the rotating motor (3) rotates, the spool (2) can also rotate at the same rotating speed. The used slender metal wire (4) of experiment can carry in carrying spout (11) and remove, and for the convenience metal wire (4) transmission in carrying spout (11), the gyro wheel (7) that are designed to have a plurality of organic glass to make in the spout are used for supplementary and direction. The metal guide roller (5) is installed at the outlet of the sliding groove, and the metal guide roller (5) is slightly higher than the common roller, so that the metal wire (4) can be tightly attached to the metal guide roller (5) when being transmitted on the metal guide roller (5), and the metal wire can also be electrified when being connected with a metal rod at one end of the metal guide roller (5). In addition, an oil tank (6) is designed between the metal guide roller (5) and the common roller (7), a funnel-shaped oil inlet hole (10) is designed above the oil tank (6), and the smoke oil required by the experiment can be injected through the oil inlet hole.
Aiming at the problems that transversely arranged metal wires are difficult to oil and are not continuous in smoke generation, the invention designs a visual experimental device for a smoke line flow field, which is suitable for transversely arranged metal wires, and comprises the following specific operation steps:
the first step is as follows: designing a metal wire conveying device:
the conveying device (1) is designed as shown in figures 1 and 2, and a rotating motor (3) is fixed at the middle position of the whole conveying device through bolts and is controlled by a power supply controller (8). A red control switch (9) and a yellow control switch (9) and a rotating speed knob (12) are designed on the power controller (8) and are respectively used for controlling the power of the rotating motor, the rotating direction of the rotating motor and the rotating speed of the motor. When the size of the designed bobbin is large, the outer diameter of the bearing of the rotating motor (3) is considered, the bobbin (2) can be directly sleeved on the bearing of the rotating motor (3), the bobbin and the bearing are fixed through the buckle at the joint of the bearing and do not move relatively, and when the rotating motor (3) rotates, the bobbin (2) can also rotate at the same rotating speed.
One end of a slender metal wire (4) used in the experiment is fixedly wound on the spool (2), when the rotating motor rotates, the metal wire (4) wound on the spool (2) can be tightened or loosened along with the rotation, the other end of the slender metal wire can move in the conveying sliding groove (11), and in order to promote the metal wire (4) to be driven in the conveying sliding groove (11), a roller (7) made of organic glass is designed in the sliding groove. In addition, at the spout exit, be equipped with metal guide roller (5), metal guide roller (5) are higher a little than ordinary gyro wheel (7) in the spout position, and the gyro wheel middle part leaves the notch, are favorable to metal silk (4) to laminate the transmission and can not the slippage on metal guide roller (5) notch like this. The metal guide roller (5) is designed with a longer metal rod support which can be used for connecting a wire for conducting electricity, and when the wire is connected with the metal rod of the metal guide roller (5), the metal wire (4) tightly attached to the metal guide roller (5) can also be electrified. Wire (4) are before transmission to metal guide roller (5), can pass oil tank (6) that contain the smoke oil, for the convenience increases the smoke oil toward oil tank (6), oil tank (6) top design has one infundibulate inlet port (10), accessible inlet port can be with outside smoke oil injection oil tank (6) in, pass from the aperture at oil tank (6) both ends when wire (4), can be stained with the smoke oil on the wire surface, the smoke oil can vaporize for smog behind the wire ohmic heating.
The second step is that: installation of the device in a wind tunnel:
installation of the wing profile: as shown in fig. 3, transparent end plates (17) are installed at two ends of the wing model (14), the whole model is horizontally placed on a frame erected by erected aluminum profiles, and the whole model is horizontally positioned in the central area of the wind tunnel. And a PIV laser head (16) is erected at the position of about 1m at the rear end of the model, the position of the laser head is adjusted, and the laser sheet light is ensured to be parallel to the incoming flow and to be vertical to the airfoil surface of the airfoil.
Installation of a conveying device of metal wires: two metal wire conveying devices (1) are respectively arranged on the outer sides of end plates at two ends of an airfoil (14), and conveying outlets are oppositely arranged. Since the two wire conveying devices (1) are completely identical, when the two devices are installed, the conveying outlets of the two devices are required to be at the same height, so that the wires between the two devices can be parallel to the spanwise direction of the wing profile. After the positions of the two metal wire conveying devices (1) on the end plates are determined, the two metal wire conveying devices (1) are connected with the end plates at the two ends of the wing shape through bolts, and two small holes for conveying and moving the metal wires are formed in the positions of the metal wire conveying outlets corresponding to the two end plates. Then, positive and negative wires (13) of a power supply are respectively connected to the metal guide rollers (5) in the two devices, so that the metal wire conveying device (1) and the wing-shaped model form a whole. When the wing section model rotates at different attack angles, the metal wire conveying device (1) also rotates along with the wing section model, and the metal wire is still parallel to the wing section spanwise direction, so that the smoke line visualization experiment under different attack angles can be carried out. In addition, the two wire feeding devices (1) can also be translated to other positions of the airfoil profile according to the experimental visualization area requirements.
The third step: installation and debugging of each device before wind tunnel experiment
After the conveying device is installed, a metal wire (4) needs to be additionally arranged in the conveying device (1), and the method for additionally arranging the metal wire comprises the following steps: one end of the wire is fixed and wound on a spool (2) in one device, in order to ensure enough transmission time of the wire, the wire can be wound on the spool (2) as much as possible, and the other end of the wire is transmitted to the other device through a conveying chute (11) and is fixedly wound on the spool (2) through a chute in the other device. After the metal wires are installed, the power controllers (8) of the two devices are simultaneously opened, the rotating motors (3) are adjusted, the rotating directions of the two rotating motors are opposite, namely the metal wires of one spool (2) are in a wire winding state and the other spool is in a wire unwinding state, then the rotating speed of the rotating motors (3) is adjusted, the rotating speeds of the two rotating motors can be matched with each other, the transmission speed of the metal wires is ensured to be proper, and the metal wires are always in a tensioned state in the transmission process.
After the metal wire is installed, a camera (15) and a laser (16) need to be adjusted, the laser (16) located behind the airfoil model (14) is adjusted, and laser is emitted to the incoming flow in parallel and is perpendicular to the metal wire (4). Marking points are made at the intersection of the laser and the metal wire, and the focal distance of the camera (15) is adjusted to the plane where the marking points are located. After the installation and debugging of each device are finished, the wind tunnel is opened firstly, and then the direct current power supply is started to electrify the metal wire.
According to the method for the visual experiment of the smoke line flow field of the transversely-arranged metal wire, the functions of automatic transmission and automatic oiling of the metal wire are realized through the conveying device, components used by the device can be conveniently obtained, and the cost of test materials is greatly saved. Meanwhile, the experimental time for adjusting the angle position of the camera according to the state change in the experiment is saved, and the precision of experimental measurement can be ensured.
As a further preferable embodiment of the present invention: the wire is preferably made of about 0.1mm long and thin 304 stainless steel, which has little disturbing effect on the flow field.
Furthermore, the shape structure material of the conveying device can be made of an acrylic plate, and can also be made of other materials.
Although the illustrative embodiments of the present invention have been described above for the understanding of those skilled in the art, the present invention is not limited to the scope of the embodiments, and various changes and modifications within the spirit and scope of the present invention as defined and defined by the appended claims will be apparent to those skilled in the art and all inventive changes that utilize the inventive concept are intended to be embraced therein.