A Computational Study of Outwash for a Helicopter Operating Near a Vertical Face with Comparison to Experimental Data

Computational fluid dynamics predictions of the downwash and outwash from the rotor of a helicopter hovering near a land-based hangar are presented. The effects of mesh density and turbulence models are studied. Spalart-Almaras turbulence modeling is shown to be more significantly affected by mesh density than either shear stress transport or monotone integrated large eddy simulation. Computational predictions are compared with experimental data and the effects of atmospheric boundary layer and inflow wind condition are investigated. Using an atmospheric boundary layer with averaged values for inflow speed and direction give the best comparisons to experimental data. The importance of obtaining accurate experimental inflow measurements is stressed.