Boundary Layer Transition Characteristics of a Full-Scale Helicopter Rotor in Hover

The final paper will discuss the transition characteristics on both sides of the full scale helicopter rotor for several hover conditions in detail. The transition locations will be quantified and valuable validation data will be provided for the transition prediction on helicopter rotors. By a omparison of the test cases at 100% and 80% RPM, the effect of the Reynolds number on the transition characteristics will be described. In addition, the prediction quality of a state-of-the-art CFD transition prediction tool will be assessed for the hovering rotor by the comparison with the experimental data. A discussion of the numerical results obtained for rigid and for elastic blades will, furthermore, allow extracting the effect of the elastic blade deformation on the transition characteristics.