1998 年 18 巻 Supplement1 号 p. 125-128
The paper introduces a quantitative measurement technique for analyzing transient deformation of liquid-liquid interface through which a sphere penetrates. Water in room temperature was filled up to 170mm depth and a layer of silicon oil was put on the water with 30mm or 40 thickness. A 6.0 mm diameter acrylic or brass ball was set first at the upper surface of the oil and then released In order to record the transient phenomenon, a high-speed video camera was employed. The upper oil is dyed dark blue help extraction of the boundaries between the two liquids. The velocities of the falling ball were determined from coordinates of the center of gravity in the sequential pictures. Along with the velocity, the volume and the interfacial area of the oil is dragged into the water. And the authors are trying to measure the velocity distribution of the entrainment flow is obtained quantitatively using PTV technique.