Acoustical liners are one of the main solutions to reduce noise in modern aircraft turbofan engines. Numerical analysis such as computational aeroacoustics proved to be an accurate and reliable tool for predicting liners performance. The impedance (or, in another form, reflection coefficient) parameter is used to evaluate the acoustic absorption capability of a surface. As the impedance is a frequency dependent variable and defined based on acoustic quantities, its calculation is a difficult

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... llenge for traditional CFD solvers, which are time-domain based and encompass both acoustic and hydrodynamic fluctuating quantities. Recent works allowed a new representation of the impedance under the form of a fractional multi-poles Time-Domain Impedance Boundary Condition (TDIBC) with a reflection coefficient formulation. The present work deals with the implementation of such TDIBC in a Finite-Volume CFD solver, with particular attention to confine the additional computational cost. Multiple validations against analytic (1D) and experimental (2D) data confirm the excellent reproduction of the noise reduction achieved by the lined wall.