| Abstract: |
| The stability of two-dimensional laminar wakes behind elliptic cylinders is studied using a reduced-order Galerkin model. This approach employs proper orthogonal decomposition (POD) to extract the dominant coherent structures from flow simulations. It constructs a reduced dynamical system by projecting the governing Navier-Stokes equations onto the subspace spanned by these modes. The resulting low-dimensional Galerkin system effectively captures the essential dynamics of the wake flow while significantly reducing the computational cost. A linear stability analysis of the reduced-order system is performed to examine the onset of wake instability and identify the critical Reynolds number where the transition to unsteady flow occurs. The study further explores the influence of cylinder aspect ratio on wake behavior and the development of wake vortex shedding patterns. The reduced model demonstrates its capability to predict wake instabilities accurately and offers insights into the flow`s sensitivity to perturbations. These findings contribute to a better understanding of laminar wake dynamics and provide a foundation for designing flow control strategies to mitigate instability in practical applications. |
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