CN111337220B - High-speed flight test flow field measurement system - Google Patents
High-speed flight test flow field measurement system Download PDFInfo
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- CN111337220B CN111337220B CN202010291303.9A CN202010291303A CN111337220B CN 111337220 B CN111337220 B CN 111337220B CN 202010291303 A CN202010291303 A CN 202010291303A CN 111337220 B CN111337220 B CN 111337220B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M9/00—Aerodynamic testing; Arrangements in or on wind tunnels
- G01M9/06—Measuring arrangements specially adapted for aerodynamic testing
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Abstract
The invention relates to a high-speed flight test flow field measuring system, which comprises a head cabin, a silk thread, a rear cabin, a recorder assembly, a camera box assembly and a video collector, wherein the head cabin is provided with a front end and a rear end; the head cabin is a research cabin section of a high-speed flight test, one end of a silk thread is fixed in a region concerned by the head cabin by adopting a planting method or a bonding method, the rear cabin is used for placing and fixing single-machine equipment and is connected with the front cabin through an axial screw, the camera box assembly penetrates through the wall and is fixed on the wall surface of the rear cabin and is used for shooting the flow field distribution of the silk thread region, and the video collector and the recorder assembly are fixed in the rear cabin and are respectively used for carrying out data acquisition and storage on the shot flow field image of the silk thread region.
Description
Technical Field
The invention relates to a high-speed flight test flow field measurement system, and belongs to the field of aerodynamic research.
Background
Numerical calculation, wind tunnel test and flight test are three means for aerodynamic research. The flight test can obtain a large amount of actual flight data through lower test cost, so as to determine the availability and the accuracy of a relevant theory and promote the further development of the theory. In the process of carrying out flight tests, the flow field change rule of the surface of an aircraft is an important research content.
The high-speed flight refers to the flight with the flight speed not less than 5 times of the sound velocity, most of the existing high-speed flight test flow field measurement methods are that a large number of temperature measurement or pressure measurement sensors are arranged on the wall surface of an aircraft structure, and the change rule of the flow field is obtained by recording and analyzing the sensor data in the flight process. Under the condition, the aircraft structure shell needs to be correspondingly processed with a large number of sensor interfaces, so that the production difficulty is high; the number of the sensors is large, so that the assembly difficulty of the product is high; the method is limited by the arrangement condition of the sensors, the flow field display is often not intuitive enough, and the data analysis difficulty is large; flow field distribution of small-sized models and curved thin airfoil surfaces cannot be obtained.
Disclosure of Invention
The technical problem solved by the invention is as follows: the high-speed flight test flow field measurement system can simultaneously meet the requirements of simplicity in production and assembly, visual measurement result, strong adaptability of model size, simplicity and reliability in measurement scheme and the like.
The technical scheme of the invention is as follows: a high-speed flight test flow field measurement system comprises a head cabin, a silk thread, a rear cabin, a recorder assembly, a camera box assembly and a video collector; the head cabin is a research cabin section of a high-speed flight test, one end of a silk thread is fixed in a region concerned by the head cabin by adopting a planting method or a bonding method, the rear cabin is used for placing and fixing single-machine equipment and is connected with the front cabin through an axial screw, the camera box assembly penetrates through the wall and is fixed on the wall surface of the rear cabin and is used for shooting the flow field distribution of the silk thread region, and the video collector and the recorder are fixed in the rear cabin and are respectively used for carrying out data acquisition and storage on the shot flow field image of the silk thread region.
Preferably, the camera box assembly comprises glass, a camera box body, a camera box cover, a camera protective shell, a camera, a cable sealing cover, a high-temperature-resistant cushion A, a high-temperature-resistant cushion B and a limiting piece; high temperature resistant blotter A and high temperature resistant blotter B distribute in the glass both sides, carry on spacingly and fix in camera box main part to the three through spacing piece, camera and camera protective housing are fixed to be in place the back as the integral erection camera box cover, and the camera lid is connected with camera box main part, and the camera cable is connected the back that targets in place, installs the sealed lid of cable at camera box main part afterbody, through the fixed and sealed of the realization cable of rubber coating in gap department.
Preferably, the camera box main body is provided with a square hole, the cross section of the glass is convex, the high-temperature-resistant cushion A is of a closed square frame structure and is sleeved on the convex, and the upper part of the convex structure is matched with the square hole; the high-temperature-resistant cushion pad B is a U-shaped frame and is arranged on the lower surface of the convex shape, and the limiting piece is of a U-shaped structure and is arranged on the camera box main body close to the high-temperature-resistant cushion pad B.
Preferably, a gap of 0.5mm is reserved between the periphery of the glass and the inner wall surface of the camera box main body, and a high-temperature sealant is fully coated in the gap.
Preferably, the camera box assembly is conformal with the outer surface of the rear cabin and the outer surfaces of the camera box assembly and the rear cabin are flush, the periphery of the camera box assembly is free of reverse airflow steps, and the forward airflow steps are not larger than 0.5 mm.
Preferably, the incident direction of the light in the silk thread area is not perpendicular to the plane of the glass.
Preferably, the same camera is matched with lenses of various specifications according to a formula
And determining a focal length range meeting the use requirement, and further determining the specification of the camera lens.
Preferably, the glass is quartz glass, can resist temperature of not less than 1000 ℃, the upper surface and the lower surface of the glass are coated with hydrophobic films, the length and the width of the glass are not more than 150mm, and the thickness of the glass is not less than 10 mm.
Preferably, the diameter of the silk thread is 0.1-1 mm, the length of the silk thread exposed out of the surface of the model is 10-80 mm, and the distance between the silk thread holes is 10-80 mm.
Preferably, the rear half cone angle is not less than 25 °, the rear half cone angle should be greater than the nose half cone angle and the difference between the two is not less than 20 °.
Preferably, the recorder assembly comprises a conformal hoop, a recorder and a connecting plate; the connecting plate is fixed in the back cabin inner wall face, and the record appearance is placed on the connecting plate, and conformal clamp is reliably fixed in between the two with the record appearance after the connecting plate is connected in place.
Preferably, the recorder has a data dual-redundancy backup function, the single machine appearance comprises a spherical surface and a cylindrical surface, stress concentration is effectively avoided, and the recorder is fixed on the connecting plate through the conformal hoop and is suitable for working environments such as landing impact.
Compared with the prior art, the invention has the beneficial effects that:
the high-speed flight test flow field measurement system can simultaneously meet the requirements of simplicity in production and assembly, visual measurement result, strong adaptability of model size, simplicity and reliability in measurement scheme and the like.
The high-speed flight test flow field measurement system can obtain a small-size model and the distribution of the flow field of the curved thin airfoil surface。
The high-speed flight test flow field measurement system is simple in composition, the overall appearance of the aircraft is not damaged after the system is introduced, and new problems brought to other systems are avoided. The system has multiple heat sealing capability and high safety.
The high-speed flight test flow field measurement system has strong adaptability and wide working range. The high-speed flight test flow field measuring system can stably and reliably work under the working conditions of normal temperature and high temperature not higher than 500 ℃. The high-speed flight test flow field measuring system can stably and reliably work under various typical working condition vibration, impact and overload environments of the rocket.
The camera, the glass, the cushion pad and the like for measuring the high-speed flight test flow field are all integrated into the camera box assembly, and the assembly is simple and reliable.
Drawings
Fig. 1 is a schematic diagram of the composition of a high-speed flight test flow field measurement system.
Fig. 2 is a schematic diagram of the components of the recorder.
Fig. 3 is a schematic view of the components of the camera box assembly of the present invention.
Fig. 4 is an exploded view of the components of the camera case assembly of the present invention.
Fig. 5 is a schematic view of the light rays refracted after passing through the transparent glass.
In fig. 1: the device comprises a first cabin 1, a silk thread 2, a rear cabin 3, a recorder assembly 4, a camera box assembly 5 and a video collector 6.
In fig. 2: 41 conformal hoop, 42 recorder and 43 connecting plate.
In fig. 3 and 4: 51 glass, 52 camera box main parts, 53 camera box covers, 54 camera protective shells, 55 cameras, 56 cable sealing covers, 57 high-temperature-resistant buffer pads A, 58 high-temperature-resistant buffer pads B and 59 limit pieces.
Detailed Description
The invention is further illustrated by the following examples.
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to fig. 1 to 5 in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1, the present invention provides a technical solution: the utility model provides a high-speed flight test flow field measurement system, includes first cabin 1, silk thread 2, backseat 3, record appearance subassembly 4, camera box subassembly 5, video collector 6, the first cabin is the research cabin section of high-speed flight test, and the silk thread adopts the bonding method to fix in the first cabin area of concern, and the backseat is used for settling fixed unit equipment and passes through axial screw with the front deck and be connected, and record appearance subassembly and video collector are fixed inside the backseat, and camera box subassembly is worn the wall and is fixed in on the backseat wall.
In the flying process, the silk thread adhered to the head cabin can display the flow field distribution condition of the area where the silk thread is located in real time, the camera shoots the flow field display condition of the silk thread area, the video collector carries out data acquisition on the image shot by the camera and stores the image into the recorder, and after the flying test is finished, the recorder is recovered to obtain the required image data, so that the change rule of the silk thread area flow field in the flying process is obtained.
As shown in fig. 2, the recorder module of the present invention includes a conformal clip 41, a recorder 42, and a connection plate 43, wherein the connection plate is fixed on the inner wall surface of the rear compartment, the recorder is placed on the connection plate, and the recorder can be reliably fixed between the conformal clip and the connection plate after the conformal clip and the connection plate are connected in place. The recorder has the function of data dual-redundancy backup design, the single machine is mainly spherical and cylindrical in appearance, stress concentration is effectively avoided, and the recorder is fixed on the connecting plate through the conformal clamp and is suitable for working environments such as landing impact.
As shown in fig. 3, the camera box assembly of the present invention includes a glass 51, a camera box main body 52, a camera box cover 53, a camera protection shell 54, a camera 55, a cable sealing cover 56, a high temperature resistant cushion a57, a high temperature resistant cushion B58, and a limiting piece 59, where the high temperature resistant cushion a and the high temperature resistant cushion B are distributed on two sides of the glass, and are limited by the limiting piece and fixed on the camera box main body, the camera and the camera protection shell are fixed in place and then integrally installed on the camera box cover, the camera box cover and the camera box main body are connected by bolts, after the camera cable is connected in place, the cable sealing cover is installed at the tail of the camera box main body, and the cable is fixed and sealed by gluing at the gap.
The camera box assembly needs to be installed through a wall, and is kept flush with the outer surface of the rear cabin based on thermal protection consideration, no reverse airflow step exists around the camera box assembly, and the forward airflow step is not larger than 0.5 mm.
The incident direction of the light in the silk thread area is not perpendicular to the plane of the glass, and when the camera is arranged, the refraction condition of the light path needs to be calculated, so that the deviation distance of the light after being refracted by the glass is obtained. In fig. 5, i is an incident angle, r is an exit angle, n is a refractive index, the glass thickness is a, n is sin i/sinr, and r is arcsin (sin i/n), and the offset distance of the light refracted by the glass can be obtained
The light ray offset distance can be obtained by substituting the refractive index of the glass and the incident angle of the specific working condition.
The same camera can be matched with lenses of various specifications according to a formula
The focal length range meeting the use requirement can be determined, and then the specification of the camera lens can be determined.
When the flow field measurement system works, the light in the silk thread area of the test flight device is ensured to be abundant.
High-temperature-resistant buffering cushions are arranged on two sides of the glass, a gap of 0.5mm is reserved between the periphery of the glass and the inner wall surface of the camera box, and the gap is fully coated with high-temperature sealant, so that the adaptability of the glass to vibration and impact environments can be improved by the measures. The high temperature resistant cushion A and the high temperature resistant cushion B can resist the temperature of more than 500 ℃ without deterioration and decomposition.
The damping pad is arranged at the joint of the mechanical interface of the camera box body and the rear cabin, a 0.5mm gap is designed between the side wall of the camera box body and the opening of the rear cabin, and the gap is coated with high-temperature sealant, so that hot air flow can be prevented from directly entering the gap, and the adaptability of product vibration and impact environment is improved.
The cable sealing cover at the tail part of the camera box body is mainly used for sealing the cable of the camera, a gap exists between the cable and the opening of the sealing cover, and the gap is filled with high-temperature sealing glue.
The transparent glass is quartz glass, has temperature resistance not lower than 1000 ℃, extremely low thermal expansion coefficient, high heat resistance, excellent chemical stability, excellent electrical insulation, low and stable ultrasonic delay performance, optimal ultraviolet spectrum transmission performance, visible light transmission performance and near infrared spectrum transmission performance, and mechanical performance higher than that of common glass, and the upper surface and the lower surface of the glass are coated with hydrophobic films. The length and width of the glass are not more than 150mm, and the thickness is not less than 10 mm.
The silk thread can be fixed by a planting method or an adhesion method and is determined according to the actual working condition. The selected filaments are soft and light and can withstand temperatures above 500K without deterioration. The diameter of the silk thread is 0.1-1 mm, the length of the silk thread exposed out of the surface of the model is 10-80 mm, and the distance between the silk thread holes is 10-80 mm.
The half cone angle of the rear cabin is not less than 25 degrees, the half cone angle of the rear cabin is larger than the half cone angle of the head cabin, the difference between the half cone angle of the rear cabin and the half cone angle of the head cabin is not less than 20 degrees, and therefore the situation that images cannot be identified due to insufficient vision is avoided.
In summary, a preferred embodiment is given in which the filaments are quartz fiber yarns, which are soft and lightweight and can withstand temperatures of 1000 ℃ without deterioration. The diameter of the silk thread is 0.8mm, the length of the silk thread exposed out of the surface of the model is 40mm, and the distance between the silk thread holes is 40 mm. The camera box assembly is in a grinding conformal shape with the outer surface of the rear cabin, and the periphery of the camera box assembly is provided with no steps. The rear cabin half cone angle is 25 degrees, and the head cabin half cone angle is 5 degrees. The selected high-temperature-resistant cushion A and the selected high-temperature-resistant cushion B are customized by adopting Dq441J-108 high-temperature glue, and the high-temperature sealants coated at the gaps of the camera assembly are both the Dq441J-108 high-temperature glue and can endure the temperature of 500 ℃ without deterioration. The transparent glass is quartz glass with the trade name of JGS1, can resist 1200 ℃, and has the length and width of 130mm and the thickness of 15 mm. The incident angle of the incident light of the measuring system is about 70 degrees, the refractive index of the glass is 1.7, the light deviation is about 10.7mm, and the position of the camera is correspondingly adjusted.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (11)
1. The utility model provides a high-speed flight test flow field measurement system which characterized in that: the device comprises a head cabin, a silk thread, a rear cabin, a recorder component, a camera box component and a video collector; the camera box assembly is fixed on the wall surface of the rear cabin in a penetrating way and is used for shooting the flow field distribution of the silk thread area, and the video collector and the recorder are fixed in the rear cabin and are respectively used for carrying out data acquisition and storage on the shot silk thread area flow field images; the high-speed flight refers to the flight with the flight speed not less than 5 times of the sound speed; the head cabin is conical, and the rear cabin is truncated cone; the half cone angle of the rear cabin is not less than 25 degrees, the half cone angle of the rear cabin is larger than the half cone angle of the head cabin, and the difference between the half cone angle of the rear cabin and the half cone angle of the head cabin is not less than 20 degrees.
2. The system of claim 1, wherein: the camera box assembly comprises glass, a camera box body, a camera box cover, a camera protective shell, a camera, a cable sealing cover, a high-temperature-resistant buffer cushion A, a high-temperature-resistant buffer cushion B and a limiting sheet; high temperature resistant blotter A and high temperature resistant blotter B distribute in the glass both sides, carry on spacingly and fix in camera box main part to the three through spacing piece, camera and camera protective housing are fixed to be in place the back as the integral erection camera box cover, and the camera lid is connected with camera box main part, and the camera cable is connected the back that targets in place, installs the sealed lid of cable at camera box main part afterbody, through the fixed and sealed of the realization cable of rubber coating in gap department.
3. The system of claim 2, wherein: the camera box main body is provided with a square hole, the cross section of the glass is convex, the high-temperature-resistant cushion A is of a closed square frame structure and is sleeved on the convex, and the upper part of the convex structure is matched with the square hole; the high-temperature-resistant cushion pad B is a U-shaped frame and is arranged on the lower surface of the convex shape, and the limiting piece is of a U-shaped structure and is arranged on the camera box main body close to the high-temperature-resistant cushion pad B.
4. The system of claim 3, wherein: a gap of 0.5mm is reserved between the periphery of the glass and the inner wall surface of the camera box main body, and high-temperature sealant is fully coated in the gap.
5. The system of claim 1, wherein: the camera box assembly is conformal with the outer surface of the rear cabin and the outer surfaces of the camera box assembly and the rear cabin are flush, no reverse airflow step is arranged on the periphery of the camera box assembly, and the forward airflow step is not larger than 0.5 mm.
6. The system of claim 2, wherein: the incident direction of the light in the silk thread area is not perpendicular to the plane of the glass.
7. The system of claim 2, wherein: the same camera is matched with lenses of various specifications according to a formula
And determining a focal length range meeting the use requirement, and further determining the specification of the camera lens.
8. The system of claim 2, wherein: the glass is quartz glass, the temperature resistance is not lower than 1000 ℃, hydrophobic films are coated on the upper surface and the lower surface of the glass, the length and the width of the glass are not more than 150mm, and the thickness of the glass is not less than 10 mm.
9. The system of claim 1, wherein: the diameter of the silk thread is 0.1-1 mm, the length of the silk thread exposed out of the surface of the model is 10-80 mm, and the distance between the silk thread holes is 10-80 mm.
10. The system of claim 1, wherein: the recorder component comprises a conformal hoop, a recorder and a connecting plate; the connecting plate is fixed in the back cabin inner wall face, and the record appearance is placed on the connecting plate, and conformal clamp is reliably fixed in between the two with the record appearance after the connecting plate is connected in place.
11. The system of claim 10, wherein: the recorder has the function of data dual redundancy backup, and the appearance of a single machine comprises a spherical surface and a cylindrical surface.
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| CN202010291303.9A CN111337220B (en) | 2020-04-14 | 2020-04-14 | High-speed flight test flow field measurement system |
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| CN202010291303.9A CN111337220B (en) | 2020-04-14 | 2020-04-14 | High-speed flight test flow field measurement system |
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| CN111337220A CN111337220A (en) | 2020-06-26 |
| CN111337220B true CN111337220B (en) | 2022-03-04 |
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