Artificial ice shapes of various geometric fidelity were tested on a wing model based on the Common Research Model. Low Reynolds number tests were conducted at Wichita State University's Beech Memorial Wind Tunnel, and high Reynolds number tests were conducted at ONERA's F1 wind tunnel. The aerodynamic performance data from the two facilities were compared at matched or similar Reynolds and Mach number to ensure that the results and trends observed at low Reynolds number could be applied and continued to high Reynolds number. For both clean and iced configurations, the data from Wichita State University and F1 agreed well at matched or similar Reynolds and Mach numbers. The lift and pitching moment curves agreed very well for most configurations. There appeared to be 0.2-0.3° offset in the angle of attack between the Wichita State University and F1 data, possibly due to different flow angularities in the test sections of the two facilities. There was also an offset in the drag values between the two facilities from an unknown cause. Overall, the data compared very well between the low Reynolds number test at Wichita State University tunnel and the high Reynolds number test at F1. This indicated that data from the low Reynolds number tests could be used to understand iced-swept-wing aerodynamics at high Reynolds number. Nomenclature b = Model span c = Model chord x = Model coordinate in chordwise direction y = Model coordinate in spanwise direction CD = Drag coefficient CD,0.6 = Drag coefficient at CL = 0.6 CD,min = Minimum drag coefficient CL = Lift coefficient CL.max = Maximum lift coefficient CL,use = Usable lift coefficient CM = Pitching moment coefficient Cp = Pressure coefficient CRM65 = Common Research Model 65% scale M = Mach number MAC = Mean aerodynamic chord ONERA = Office National d'Etudes et Recherches Aérospatiales p0 = Freestream total pressure q = Freestream dynamic pressure Re = Reynolds number RLE = Removable leading edge  = Angle of attack stall = Stall angle of attack  = Sweep angle

Aerodynamic assessment of icing effects on swept wings is an important component of a larger effort to improve three-dimensional icing simulation capabilities. An understanding of ice-shape geometric fidelity and Reynolds and Mach number effects on the iced-wing aerodynamics is needed to guide the development and validation of ice-accretion simulation tools. To this end, wind-tunnel testing was carried out for a 13.3%-scale semispan wing based upon the Common Research Model airplane configuration. The wind-tunnel testing was conducted at the ONERA F1 pressurized wind tunnel with Reynolds numbers of 1.6×10 6 to 11.9×10 6 and Mach numbers of 0.09 to 0.34. Five different configurations were investigated using fully 3D, high-fidelity artificial ice shapes that maintain nearly all of the 3D ice accretion features documented in prior icing-wind tunnel tests. These large, leadingedge ice shapes were nominally based upon airplane holding in icing conditions scenarios. For three of these configurations, lower-fidelity simulations were also built and tested. The results presented in this paper show that while Reynolds and Mach number effects are important for quantifying the clean-wing performance, there is very little to no effect for an iced-wing with 3D, high-fidelity artificial ice shapes or 3D smooth ice shapes with grit roughness. These conclusions are consistent with the large volume of past research on icedairfoils. However, some differences were also noted for the associated stalling angle of the iced swept wing and for various lower-fidelity versions of the leading-edge ice accretion. More research is planned to further investigate the key features of ice accretion geometry that must be simulated in lower-fidelity versions in order to capture the essential aerodynamics. Determine the level of ice-shape geometric fidelity required for accurate aerodynamic simulation of sweptwing icing effects. This paper, along with a series of companion papers, 5-7 provides initial results for these remaining objectives. Additional wind-tunnel testing and future publications are planned. The approach used to accomplish these objectives has been successfully carried out in previous icing aerodynamics studies of straight wings and airfoils.In past work, geometric representations of ice accretion have been attached to wings and models and tested in dry-air wind tunnels or in flight. These geometric representations are known as "artificial ice shapes" or "iceaccretion simulations." The various methods and geometric fidelities associated with developing artificial ice shapes have been investigated in a previous NASA-ONERA collaborative research effort called "SUNSET1." 8 Since that time, a new approach for producing high-fidelity artificial ice shapes have been developed using 3-D scanning and rapid-prototype manufacturing (RPM). 9 In past studies of icing performance effects on airfoils, systematic investigations of Reynolds and Mach number effects were conducted. [10][11][12][13][14][15][16] Over the course of many years, it was fo...

No abstract

No abstract