Projector-based quantitative background schlieren method temperature measuring device and method

Abstract

The invention discloses a projector-based quantitative background schlieren method temperature measuring device and method, and the device and method are used for measuring the density and temperature of a flow field. Based on the principle that a background schlieren method is used for measuring medium physical property parameters, a projector is used for generating random background points to serve as a light source to replace original printing background points and background light sources. The experimental device is composed of a background point generation device, a projection system, an imaging system and an image processing device. According to a traditional background schlieren method, different background points need to be printed under different experiment conditions to guarantee the measurement precision, additional background light source illumination is needed, the experiment process is tedious, and experiment devices are complex. According to the invention, the projection pattern is used for replacing the printing background point, the background pattern can be directly generated according to the measurement requirement to ensure that the resolution of the background point is matched with the resolution of the camera, and the defect that different background points need to be printed for different experimental devices is overcome. Meanwhile, the projector provides sufficient background light intensity while providing background points, so that the cost is saved while the imaging quality requirement is met.

Description

technical field [0001] The invention relates to the field of quantitative measurement by schlieren method, in particular to a measuring device and method for measuring flow field temperature by a projector-based quantitative background schlieren method. Background technique [0002] As a non-contact optical flow field display method, the schlieren method has been widely used in the observation of flow fields such as gas jets, plasmas, and flames. Background of the Technology Schlieren technology is gradually developed. This method can realize quantitative measurement of flow field density and temperature with simple experimental devices and algorithms, and is widely used in the field of flow field diagnosis. [0003] The background schlieren technology is the same as the traditional schlieren technology. The flow field parameters are determined based on the deflection angle of the light after passing through the flow field. Extract the offset of the background point in the ...

AI Technical Summary

Problems solved by technology

If a liquid crystal display is used as the background display device, although the problem of how to quickly change the background pattern is solved, the image quality will be affected due to the low brightness of the display screen and the refresh rate is significantly lower than the shutter speed of the camera, which will bring more problems to the subsequent processing. big error

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