Symmetry breaking and spiral similarity of Oseen-like vortex in confined compressible fluid

Abstract

Abstract Vortex flow has been widely observed in fluid systems in confined regions. In this study, an Oseen-like vortex in a confined compressible fluid was numerically investigated to understand its distinct patterns and associated symmetries. The vortex was studied within multiple two-dimensional polygon confined fluid domains (with different orders) with a rotational solid core in the center. It was demonstrated that the vortex in a compressible fluid is governed by two coexisting mechanisms. Dynamic viscosity provides a circular pattern that is diffusive from the core to the boundary. Shock dynamics provides the mechanism of starry patterns with distinguished arm-like features. The presence of arm-like features alters the symmetries of the original Lamb-Oseen vortex and manifests sensitivity to the initial rotational conditions. In summary, the combined influence of the two coexisting mechanisms generates distinct features from the original Lamb-Oseen vortex. The understanding of the vortex development and features is useful to develop levitation device in microgravity science.