Method and system for calculating propagation velocity of shock wave generated by discharge

Abstract

The present application discloses a method and system for calculating the propagation velocity of shock waves generated by discharge, including: acquiring two continuous schlieren pictures A and B with shock waves generated during the discharge process; extracting the schlieren pictures A and B respectively; The shock wave surface contour line in B, the shock wave surface contour line of the adjacent time is registered in one picture; the data points of the shock wave surface contour line are expanded to form the time of the schlieren pictures A and B for the same process flow field Sequence wavefront point coordinate set, denoted as A data and B data ; for A data and B data After segmentation, determine the shock wave propagation direction, shock wave radius, and shock wave propagation velocity value of each point on the shock wave surface contour line in the schlieren images A and B, and obtain the final shock wave propagation velocity. The requirement for the spatial resolution of the high-speed camera used for experimental observation is reduced, the workload of manual point selection is reduced, and the propagation speed of the shock wave generated in the discharge process can be accurately reflected.

Description

technical field [0001] The invention belongs to the field of image processing, and relates to a method and system for calculating the propagation velocity of shock waves generated by discharge. Background technique [0002] The shock velocity is one of the important characteristics of the shock wave, which is generally calculated by the ratio of the measurement value of the sensor and the time interval between the measurement signals. Commonly used shock velocity measurement methods are: [0003] (1) Measure the shock wave pressure signal through the pressure sensor: [0004] Common pressure sensors include piezoelectric sensors and piezoresistive sensors. During the experiment, each sensor needs to occupy an amplifier channel and a data acquisition channel. When more measurement points are required, the use of pressure sensors for measurement will result in high measurement costs. At the same time, in a small measurement range, especially in some positions, only the sho...

AI Technical Summary

Problems solved by technology

However, the shock wave front has a certain thickness, and it is impossible to connect a single pixel to form a wave front profile, which will lead to a many-to-many situation when looking for corresponding points

At the same time, limited by the low resolution of the schlieren image, the effective data points on the wave surface are limited, and incorrect results will be obtained when calculating the direction and velocity of shock wave propagation, resulting in large calculation errors

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