This paper presents a computational study of the formation and ingestion of ground vortices and resulting fan forced response levels in a large turbofan operating near the ground. The model is based on an integrated aeroelasticity numerical method; the aerodynamic part is based on a 3D unstructured Reynolds-Averaged Naveir-Stokes solver. The mechanical model uses linear modal model for the structure, allowing for the direct computation of the structural response during the unsteady simulations. The analysis shows that under certain fan speed and mass flow rate conditions, for a given fan and intake combination, situated at a fixed distance from the ground, an inlet vortex can form near the ground. This inlet vortex is drawn into the intake causing inlet distortions that could excite several low engine order harmonics of the fan. Predictions are compared with measured data showing good agreement in general. Ability to predict the level of response at the design stage allows for implementing design solutions preventing possible failure due to high cycle fatigue.

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