Global Stability Analysis of Flow Past Two Side-by-Side Circular Cylinders at Low Reynolds Numbers by a POD-Galerkin Spectral Method

A proper orthogonal decomposition (POD) method is applied to the problem of a two-dimensional flow past two side-by-side circular cylinders. Based on the POD bases, which are constructed by a snapshot method, a low-dimensional model is established for representing two-dimensional incompressible Navier-Stokes equations. Coupled with the low-dimensional model, the Chiba method is used to analyze the global stability of the basic flow. Different bifurcation paths at three major regions are revealed, in good agreement with the available results by other methods. However, the computation amount in the POD method is low, which shows the availability and advantage of the POD method.