基于数字图像相关方法的导爆管爆速测试研究

Experimental Study on Nonel Tube Detonation Velocity by Digital Image Correlation Method

高速摄影机为导爆管传爆特性研究提供了一种有效工具,但传统方法采用人工处理图像,测量结果受主观影响较大。因此,提出了一种基于数字图像相关方法的导爆管爆速测试方法。采用高速摄影机拍摄导爆管传爆过程图像序列并进行预处理。分别从爆轰波成长区和稳定区图像中选取波头图像模板,依据数字图像相关原理将模板与后续图像进行相关匹配以确定图像序列中波头的坐标,进而计算爆速和成长区间。采用折返式布线,布置4.5 m导爆管,观测到了导爆管内爆轰波全长。结果表明导爆管稳定爆速为1700~1800 m/s,在拐弯处降至1600~1700 m/s,成长区间为32~41 cm。同时探讨了导爆管内爆轰波模型,依据灰度值高低将爆轰波划分为有效反应区和产物膨胀区,长度分别为31.92 cm和1.05 m。

High-speed camera is an effective tool for detonation propagating process research of Nonel tube.However,the traditional method using artificial processing images,which is affected by the subjective measurement.Therefore,a new detonation velocity test method based on digital image correlation was proposed.Image sequence of detonation propagation process in Nonel tube was captured and preprocessed by a high-speed camera.The detonation wave templates were selected in the growth zone and the stable zone.Then,correlation matching was performed with the templates and the sequence images to locate the wave heads in the subsequent images.Besides,the detonation velocity and growth range can be calculated.4.5 m Nonel tube was arranged on the blackboard in zig-zag type and full detonation wave was photographed.The result indicates that the detonation velocity stabilizes at 1700~1800 m/s in straight line and 1600~1700 m/s in corners and the growth range is 32~41 cm.Meanwhile,the detonation wave model in the Nonel tube was discussed.The detonation wave can be divided into the effective reacting region and the product expansion region according to the gray value in images,and the lengths of the two regions are 31.92 cm and 1.05 m,respectively.