基于MATLAB的超声空化场表征与三维可视化

Measurement and Visualization of Ultrasonic Cavitation Field Based on MATLAB

超声空化场强度逐点扫描的测量方法耗时耗力,不利于其应用,铝箔腐蚀法廉价易得,操作简单,对空化场影响小,但定量性差.以铝箔腐蚀法测定超声清洗槽中的空化强度,铝箔样品干燥后经扫描仪采集黑白图像,导入MATLAB软件图像处理系统,编写程序提取腐蚀点位置,统计腐蚀区域占整体区域的面积比,以腐蚀面积比大小衡量超声空化强弱程度实现测量结果的量化.构造三维腐蚀面积比数据集,以不同颜色代表不同腐蚀强度将数据绘制于三维坐标系内,可实现超声空化场可视化,任意平面内空化场强度分布图可通过切片技术获得.将超声空化场表征结果进行切片分析,得到单换能器空化场分布规律的同时验证表征方法的可靠性,为超声强化过程机理研究奠定分析基础.

The common technique for determining spatial sound pressure fields is to scan the sound field pointwise, which is time-consuming and expensive and thus limits its application in the industry. Aluminum foil erosion method is cheap and easy to operate and has little effect on cavitation field, but it cannot be quantified. In this paper, aluminium foils were used to measure the distribution of the ultrasonic cavitation field in an ultrasonic cleaning vessel. Foil sample was dried, and black and white images were collected by the scanner image processing system and then imported into the MATLAB software. The MATLAB programs help to find out the position of the erosion point and calculate the ratio of the erosion area to the entire area. The erosion ratios can reflect the intensity of the cavitation, which means that the quantitative result has been achieved. Three-dimension erosion ratio data set was then built. The visualization of the cavitation field was realized by graphing the data in a spatial coordinate system using different colors to represent the variation of cavitation intensity. The distribution of the cavitation field on any planes can be derived by slicing the cavitation field. The result analysis shows that the spatial distribution regularity of the single transducer ultrasonic cavitation field can be derived and the reliability of the measure method can be verified in the mean time.