Three-dimensional flow field high-frequency measurement device and method based on sheet light scanning particle image

Abstract

The invention relates to a three-dimensional flow field high-frequency measurement device and method based on sheet light scanning particle images, and belongs to the field of experimental fluid mechanics research. The device includes a laser, a rotating gear with N reflective teeth, a stepping motor, a cylindrical concave lens, a cylindrical convex lens, two high-speed cameras, a synchronizer and a computer; wherein, N equal-spaced The threaded reflective teeth are arranged and overlapped end to end. During the rotation of the rotating gear, the incident laser beam with a constant axis distance is reflected as a reflected laser beam that scans sequentially in one direction in a fixed plane, and passes through the cylindrical concave lens, cylindrical surface After the convex lens is converted into a scanning rectangular sheet of light; because each reflective tooth realizes one scan, the actual three-dimensional scanning speed of the present invention can reach N times the speed of the stepping motor, truly realize the high-frequency measurement of the three-dimensional flow field, and obtain the three-dimensional flow field The evolution process of time and space has important application value to the experimental research of fluid mechanics.

Description

technical field [0001] The invention belongs to the research field of experimental fluid mechanics, in particular to a three-dimensional flow field high-frequency measurement device and method based on sheet light scanning particle images. Background technique [0002] The turbulence of water flow has strong temporal and spatial variation characteristics. For a long time, scientific and technological workers have used various methods to measure the three-dimensional flow field, such as three-dimensional velocity measurement technology on a two-dimensional plane, three-dimensional particle tracer velocimetry technology, defocused particle image Velocimetry technology, holographic particle image velocimetry technology, tomographic particle image velocimetry technology and sheet light scanning particle image velocimetry technology, etc. [0003] The three-dimensional velocity measurement technology on a two-dimensional plane is to use laser light to illuminate the tracer partic...

AI Technical Summary

Problems solved by technology

The three-dimensional velocity measurement technology on a two-dimensional plane can only obtain the three-dimensional flow velocity on a plane, but cannot obtain the real three-dimensional flow field in a volume

However, both the galvanometer method and the rotating drum method are limited by the rotation speed of the stepping motor and the manufacturing accuracy of the stepped mirror, and the frequency and range of sheet light scanning are relatively low. Therefore, the current sheet light scanning particle image velocimetry technology Small size, measurable flow rate and low sampling frequency

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