Figure 1
From: Bubble formation and scale dependence in free-surface air entrainment
Free-surface entrapped deformation and bubble–entrainment process. (a) High–speed video images of the entire life of the free surface entrapment deformation and air entrainment process. Image sequences are captured at 1/3000 s with 1280 (width) × 344 (height) pixels and a spatial resolution of approximately 4 pixels/mm. The shutter speed is 0.23 μs. (b) Binary image for determining the length scale of the entrapment surface and entrained air bubble. (c) Size scales of the width L, depth y, and radius of curvature r of the entrapped surface throughout the entire lifetime, including the incipient, evolving, instable and air entrainment periods. The radius of curvature at the apex of the entrapped surface r is defined from mathematics39 as r = 0.125·L·(L/y). The right axis shows the corresponding correlation coefficient Rsquare of the Gaussian–type curve for the entrapment deformation. (d) Comparison of the entrapment deformation with the Gaussian–type curve.
