A finite element study of the onset of vortex shedding in a flow past two-dimensional circular cylinder

Abstract

The objective of this investigation is to study the onset of vortex shedding. The simulation of the flow throws deep insight into the wake-zone dynamics. The diagnostic tools such as Fast Fourier Transform and phase portrait are used to understand the wake dynamics better. Furthermore, a stability analysis is accomplished by involving the complex Stuart-Landau model. The critical value of the Reynolds number is estimated from the Landau constants that correspond to the non-linearity. Three different blockages were considered in this study and are found that the critical values of the Reynolds number and the Strouhal number are sensitive to the blockage ratio. The Landau model was suggested for the local wake variable rather than a global variable. The bifurcation diagram, culminated from the simulation results, clearly reveals the occurrence of super critical Hopf bifurcation.