This paper presents a framework comprising a hybrid computational aeroacoustics (CAA) solver and a nu-merical phase-conjugation technique to localize flow-induced noise sources generated by bodies immersed in low Mach number flows. The test-case of flow over a two-dimensional circular cylinder at Reynolds number $Re = 150$ and Mach number $M = 0.2$ was considered. The hybrid CAA simulations were carried out in OpenFOAM wherein the two-dimensional unsteady, incompressible Navier-Stokes equations were solved using the pressure-implicit splitting of operators (PISO) algorithm. The near-field aerodynamic sources were extracted in terms of the unsteady Lighthill stress tensor terms, following which the far-field acoustic data was computed using Curle’s analogy. The PISO solver-based hybrid method accurately captures the vortex-shedding and the Aeolian tone as effectively as the Direct Numerical Simulation (DNS) method. Next, the frequency-domain phase-conjugation (PC) method was implemented in the finite-element (FE) based COM-SOL Multiphysics using the boundary data obtained from the hybrid CAA solver to reconstruct the radiated acoustic pressure field, whereby the dipole source location was readily identified by a pair of focal spots at the cylinder.

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