Comparison of rotor inflow models for flight simulation fidelity

Güner, Feyyaz
In real-time rotorcraft simulations, there are various dynamic inflow models to chose from. Although dynamic inflow models are well documented in literature, a comparisons of them are not commonly available. In this thesis, dynamic inflow models commonly used in flight simulators are, namely uniform inflow, extesion of uniform inflow with Payne’s coefficients, Pitt-Peters inflow and Peters-He inflow model with higher harmonics, integrated to a well-known blade element model. A theoretical background for dynamic inflow models are given. Blade element model and trimming methods are explained. The considered dynamic inflow models are compared with three different sets of experimental data. First, computed induced flow field for tapered and rectangular blade configurations are compared with the measured inflow. Secondly, the effects of induced flow variation over the flapping dynamics is examined. Finally, the dynamic inflow models are compared in terms of steady-state performance predictions. In all comparisons, inflow distributions on the rotor disk are given and related observations are presented. The fidelity of the dynamic inflow models are summarized and recommendations are given. 


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Citation Formats
F. Güner, “Comparison of rotor inflow models for flight simulation fidelity,” M.S. - Master of Science, Middle East Technical University, 2016.