Numerical and Experimental Investigation of Helicopter Fuselage Aerodynamics

The aerodynamic characteristics of an isolated MRH 90 helicopter fuselage have been investigated using Computational Fluid Dynamics (CFD). Simulations utilised an unstructured tetrahedral grid and both the k-ε and k-ω SST turbulence models were investigated. Standard ‘law of the wall’ wall functions were incorporated, along with a segregated finite volume solver. A wind tunnel testing program was also undertaken to provide a benchmark for comparison. Reasonable levels of agreement were obtained between numerical and experimental results, with the majority of cases falling within ten percent. Prediction of drag values was found to be the most difficult, which is likely to be a function of the inability to fully resolve the boundary layer. It was proposed that errors in lift and side forces at extreme orientations could result partially from wind tunnel support interference effects.