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The purpose of this study is to investigate the effects of the size and location of wind fences on the rotor performance to avoid as well as quantify any adverse effects of outside wind on the measurement accuracy. To this end, firstly, a novel actuator disk method is developed which couples open source CFD code named OpenFOAM with blade element method and rotor flapping equations. Secondly, the parametric studies are conducted with respect to wind fence configurations which contain fence radius, inlet/outlet duct size and location etc. For quantitative evaluation of rotor performance variation according to inlet/outlet duct size, the mass flow and momentum rate on the ducts are. The rotor performance variation depending on the wind fence configuration is examined and consequently parametric study cases are classified according as calculated rotor thrust coefficient. Moreover, it is explained the difference of flow field in wind fence by demonstrating the pressure coefficient.

A numerical analysis is conducted to investigate the performance degradation of iced airfoils in terms of meteorological parameters. Reference ice accretion shapes are taken from NASA's icing wind tunnel test results. Ice accretion shape and aerodynamic performance of the airfoil are numerically calculated under the same conditions as those used in the tests, and response surface equations are generated based on the results. The response surface models are applied to the conditions specified in Federal Aviation Regulations, appendix C of part 25, and the changes in aerodynamic coefficients are investigated. The areas of most significant lift and drag performance degradation overlap. The lift coefficient plunges more than 50% under temperatures greater than −10°C and LWC greater than 2g/m3. Under the same conditions, the drag performance greatly decreases as well. On the other hand, the moment coefficient greatly decreases under temperatures of less than −40°C and greater MVD.