Non-contact measurement of free surface profiles in wormlike micellar solution flowing around a cylinder based on a background-oriented Schlieren method

Abstract

Solid-like fragmentation of viscoelastic magma is an important factor in triggering explosive eruptions. This fragmentation occurs near the free surface of flowing magma. Therefore, we focused our attention on the fracturing phenomena that occur in the flow around a moving cylinder of a Maxwellian fluid, a wormlike micellar solution. The time variation of the free surface was measured by the fast checkerboard demodulation (FCD) method, a type of background-oriented Schlieren imaging. The results show that the curvature of the free surface just before fracture is similar for different diameters and moving speeds of the cylinder.