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Hypersonic wind tunnel model attitude angle measurement method based on schlieren images

A measurement method and model attitude technology, which can be used in image enhancement, image analysis, measurement devices, etc., to solve problems such as extra design and installation space and increase the uncertainty of measurement results.

Active Publication Date: 2021-04-23
INST OF HIGH SPEED AERODYNAMICS OF CHINA AERODYNAMICS RES & DEV CENT
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  • Application Information

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Problems solved by technology

However, the former has higher requirements on the working environment, especially the temperature, and requires additional design of installation space in the model, which has great limitations in the use of small-scale hypersonic wind tunnels or high Mach number tests; while the latter requires additional installation space in the wind tunnel. The optical path of the model is set on the model, and the vibration during the test will change the position and attitude of the camera, increasing the uncertainty of the measurement results

Method used

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  • Hypersonic wind tunnel model attitude angle measurement method based on schlieren images
  • Hypersonic wind tunnel model attitude angle measurement method based on schlieren images
  • Hypersonic wind tunnel model attitude angle measurement method based on schlieren images

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Embodiment 1

[0073] Taking a test in a hypersonic wind tunnel as an example, the whole process of model angle-of-attack schlieren image measurement is described in detail.

[0074] Such as figure 2 As shown, the schlieren system in the hypersonic wind tunnel uses the deflection of light generated by the inhomogeneity of the air medium to image the flow field, and is currently the most frequently used flow display tool in wind tunnel tests. The reflective parallel light schlieren system is mostly used in the schlieren system in the hypersonic wind tunnel. It can be seen from the figure that the light emitted from the point light source becomes a parallel beam after passing through the reflector 1, and the parallel beam passes through the optical observation window of the test section and reaches the reflector 2. Part of the light source image is cut off and finally imaged by the camera lens. Due to the parallel beam between the two mirrors, opaque model areas can be accurately projected ...

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Abstract

The invention discloses a hypersonic wind tunnel model attitude angle measurement method based on schlieren images. The method comprises the steps: a, selecting a model characteristic line; b, preprocessing the images; c, identifying a feature line; d, solving a model feature line attack angle; and e, solving the attack angle of the model. The method is simple and convenient, easy to implement and accurate in result, does not generate extra interference on a model flow field in the measurement process, has no special requirements on model processing, does not need to add extra equipment in a wind tunnel, can be used for correcting wind tunnel previous test data, and can be popularized and applied to attack angle measurement of other high-speed wind tunnel models with schlieren equipment.

Description

technical field [0001] The invention belongs to the technical field of hypersonic wind tunnel tests, and in particular relates to a method for measuring attitude angles of hypersonic wind tunnel models based on schlieren images. Background technique [0002] The hypersonic wind tunnel is an important ground test equipment in the development of hypersonic aircraft. Compared with other wind tunnels, the hypersonic wind tunnel operates at a high Mach number and the total temperature of the flow field is high. The aerodynamic heating of the model and support system during the test is very high. Seriously, especially in the case of high Mach number, the support system is prone to thermal deformation after being heated, resulting in changes in the attitude angle of the model. However, the traditional model attitude angle measurement method based on "mechanism angle of attack measurement + elastic angle correction" cannot Considering the influence of aerodynamic heating, there is a...

Claims

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Application Information

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IPC IPC(8): G01M9/06G01M9/08G06T5/00G06T7/13G06T7/73
CPCG01M9/06G01M9/08G06T7/73G06T7/13G06T2207/20164G06T5/70Y02T90/00
Inventor 郭鹏张鑫胥继斌杨永能马涛张长丰毛代勇李阳
Owner INST OF HIGH SPEED AERODYNAMICS OF CHINA AERODYNAMICS RES & DEV CENT
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