In-flight icing of UAVs – the influence of flight speed coupled with chord size

Abstract

The intensive deployment of unmanned aerial vehicles (UAVs) for surveillance and reconnaissance missions during the last couple of decades has revealed their vulnerability to icing conditions. At present, a common icing avoidance strategy is simply not to fly when icing is forecast. Consequently, UAV missions in cold seasons and cold regions can be delayed for days when icing conditions persist. While this approach limits substantially the failure of UAV missions as a result of icing, there is obviously a need to develop all-weather capabilities. A key step in accomplishing this objective is to understand better the influence of a smaller geometry and a lower speed on the ice accretion process, relative to the extensively researched area of in-flight icing for traditional aircraft configurations characterized by high Reynolds number. Our analysis of the influence of Reynolds number on the ice accretion process is performed for the NACA0012 airfoil. Analytical analysis of the integrated mass and energy bal...