【作者】 梁楚楚； 史仕荧； 吴应湘；

【Author】 LIANG Chu-chu;SHI Shi-ying;WU Ying-xiang;Institute of Mechanics,Chinese Academy of Sciences;

【机构】 中国科学院力学研究所；

【摘要】 基于摄影法,通过实验研究了液滴在无限大静止流场中的形态和运动学特征。用单个相机记录了在纯水中周期性被释放的大、小油滴的运动行为,通过相关图像处理技术,得到了液滴的运动轨迹、形状、长径比和水平、竖直方向速度在空间上的分布。分析发现大油滴容易发生形状振荡,同时伴随着轨迹从直线到"之"字形的过渡,而小油滴几乎保持球形,其运动轨迹始终保持"之"字形。大、小油滴的水平和竖直瞬时速度在高度方向上的分布有所不同,油滴的竖直速度和长径比之间存在反函数关系。更多还原

【Abstract】 We investigate experimentally the shape and motion characteristics of drops rising through the infinite stagnant liquids based on photography in this paper.The movement behavior of the big and small oil drops released periodically into the pure water was captured by a single camera.The drop trajectory,shape,aspect ratio,horizontal velocity and vertical velocity were obtained by using some image processing techniques.It was founded that big drops tend to display shape oscillations,which is accompanied by path transition from rectilinear to zigzag motions.On the other hand,small drops almost remain spherical and proceed in a zigzagging motion.The distributions of instantaneous horizontal velocity and vertical velocity along the direction of height are distinct and there exists an inverse function relationship between the vertical velocity and aspect ratio of the drops.更多还原