Zonal Detached Eddy Simulation of a simplified nose landing-gear for flow and noise predictions using an unstructured Navier-Stokes solver

Abstract

A Zonal Detached Eddy Simulation has been performed on the simplified LAGOON nose landing gear geometry using a Navier-Stokes solver on a fully unstructured grid. The attached boundary layers have been finely resolved using Y+ values in the order of unity, while the high curvature zones have been intensively meshed in order to accurately solving adverse pressure gradients present in these regions. The mean and fluctuating flow fields have been compared with the experimental results, proving that both the mean flow field and the spectral content recorded at the wall are accurately reproduced. Following these comparisons, a detailed analysis of the topology of the flow has been carried out through the analysis of the skin friction coefficient and friction lines, coupled with three dimensional visualizations of the landing gear wake. The far-field acoustics, computed through the Ffowcs-Williams and Hawkings equation from the computed pressure on the landing gear skin, has been compared with the experimental results, obtaining a very good agreement for the different microphones and directions. Finally, the CFD methodology presented in this study proves to be a moderate cost approach, enabling an accurate flow and noise prediction for bluff bodies such as landing gears.