Image processing method for measuring the transition position of laminar airfoil based on temperature-sensitive paint technology

Abstract

The invention discloses a laminar flow wing transition position measurement image processing method based on temperature-sensitive paint technology, comprising: S1, image acquisition, using temperature-sensitive paint technology to process the surface of laminar flow wing The predetermined position on the surface of the laminar airfoil is marked, and the camera is used to collect the background image, reference image and test sequence image of the laminar airfoil in the wind tunnel; S2, image registration; S3, image processing, and based on the light intensity ratio Convert and calculate the relationship between the sequence image and the calibration coefficient of the temperature-sensitive paint to obtain the heat flow data image on the surface of the laminar airfoil; S4. Determine the transition area and Transition location. The invention provides an image processing method for measuring the transition position of a laminar flow wing based on a temperature-sensitive paint technology, which is used for image data processing of the temperature-sensitive paint technology for measuring the transition position of a laminar flow wing. Stream wing transition area and transition location.

Description

technical field [0001] The invention belongs to the field of image information processing of wind tunnel optical measurement test technology, in particular to a method for measuring image processing of the transition position of a laminar airfoil based on temperature-sensitive paint technology. Background technique [0002] In order to achieve the goals of energy saving and emission reduction and increasing the range, the aerodynamic drag reduction technology of aircraft has become the focus of aerodynamic designers. With the rapid development of aviation industry design technology and manufacturing process, laminar flow design has gradually become possible. For civil passenger aircraft, the laminar flow wing design technology can reduce frictional resistance by about 30%, and then can improve cruise efficiency by about 15%. noise. In order to test the laminar flow wing design method and the aerodynamic characteristics of the laminar flow wing, the measurement or prediction...

AI Technical Summary

Problems solved by technology

There are many defects in this method: First, because the sensor protruding or recessing on the surface of the wing model will interfere with the surface flow field, which will cause differences in the airflow velocity or flow field structure on the surface of the wing, which will cause surface temperature measurement errors, so the sensor is required Strictly flush with the surface of the wing model, it is difficult to install the sensor

2. To install the temperature sensor, it is necessary to make holes and grooves on the wing model at the installation position and the wiring channel, which increases the difficulty of model design and processing, and increases the cost of model design and processing

3. On thin parts such as the wingtip or the trailing edge of the wing, the temperature sensor may not be installed due to insufficient thickness space, so that the transition position measurement of the above-mentioned area cannot be performed

4. The temperature sensor belongs to the discrete point measurement method, which can only measure several points on the surface of the wing. The spatial resolution is very low, and the accurate transition position of the laminar flow wing cannot be obtained.

[0005] In short, the traditional temperature sensor transition measurement method is difficult to install, has large flow disturbance, high cost of model design and processing, can only perform point measurement, and has low spatial resolution. Optical measurement methods such as phosphorescence heat map and other optical measurement methods have limited application range due to their own inherent defects, and cannot accurately measure the transition position of the wing model

The temperature-sensitive coating method has the advantages of surface measurement, high spatial resolution, difficulty in model design and processing, low cost, no disturbance of incoming flow, and accurate judgment of transition position. However, it has not been applied to the measurement of laminar flow wing transition position. Its related image processing methods urgently need to be established

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