Emissions, fuel burn, and noise are the main drivers for innovative aircraft design. Embedded propulsion systems, such as for example used in hybrid-wing body aircraft, can o er fuel burn and noise reduction bene ts but the impact of inlet ow distortion on the generation and propagation of turbomachinery noise has yet to be assessed. A novel approach is used to quantify the e ects of non-uniform ow on the creation and propagation of multiple pure tone (MPT) noise. The ultimate goal is to conduct a parametric study of S-duct inlets to quantify the e ects of inlet design parameters on the acoustic signature. The key challenge is that the e ects of distortion transfer, noise source generation and propagation through the non-uniform ow eld are inherently coupled such that a simultaneous computation of the aerodynamics and acoustics is required to capture the mechanisms at play. The technical approach is based on a body force description of the fan blade row that is able to capture the distortion transfer and the blade-to-blade ow variations that cause the MPT noise while reducing computational cost. A single, 3-D full-wheel CFD simulation, in which the Euler equations are solved to second-order spatial and temporal accuracy, simultaneously computes the MPT noise generation and its propagation in distorted inlet ow. A new method of producing the blade-to-blade variations in the body force eld for MPT noise generation has been developed and validated. The numerical dissipation inherent to the solver is quanti ed and used to correct for non-physical attenuation in the far-eld noise spectra. Source generation, acoustic propagation and acoustic energy transfer between modes is examined in detail. The new method is validated on NASA's Source Diagnostic Test fan and inlet, showing good agreement with experimental data for aerodynamic performance, acoustic source generation, and far-eld noise spectra. The next steps involve the assessment of MPT noise in serpentine inlet ducts and the development of a reduced order formulation suitable for incorporation into NASA's ANOPP framework.