水下气泡场探测全息图的数字再现技术

针对水下环境,探讨了数字全息术和图像处理技术在水下气泡场全息图的再现、识别和提取中的应用。首先完成数字全息记录及重现程序的编写并拍摄水下气泡场全息图,对全息图进行去噪处理,然后对处理过的全息图进行再现,利用边缘检测技术识别气泡并计算气泡大小,用邻域再现法统计出全息图中的气泡数目,实验证明这一方案切实可行。

基于数字全息术的水中气泡场获取方法的研究

水中气泡场是海洋和大气热交换的重要媒介,随着对海洋研究的深入,水中气泡场的研究越来越受到人们的重视。数字全息术由于具有可获取三维空间信息、可进行实时实地测量、不干扰被测对象等优点,所以可成为获取水中气泡场的有效手段。研究了数字全息技术在水中气泡场探测中的应用,并进行了数字全息拍摄的实验和再现,探讨了获取水中环境对获取气泡场的影响,讨论了实验中出现的问题,并对所得到的再现图像数据进行了分析和讨论。

Cavitation field from a horn—A new model

The cavitation field from a horn-type transducer is experimentally probed by the optical method.Based on these observations,we propose a model of the field which hypothesizes that most violent caviation bubbles originate from the vibrating surface and there-from fast drift to the near liquid region.These bubbles are chiefly responsible for the practical applications of cavitation for a large power input to the transducer.During migration they become weakened.Cavitation bubbles are also produced in the liquid region by the acoustic wave directly emitted by the transducer,but these bubbles are weak due to the shielding effect of the bubbles clinging to the transducer vibrating surface.Consequently,only weak cavitation bubbles exist in the far liquid region.