Characterization of the Spray System of the TerraXcube Icing Wind Tunnel

In recent years, the field of Unmanned Aerial Vehicles has shown great technological progress, and many new applications were born. To assess the potential of this technology and to improve the availability and reliability of the rising services it is critical to overcome operational limitations. One key operational hazard is atmospheric in-flight icing, resulting in large aerodynamic penalties, unbalances and other detrimental phenomena that can sometimes lead to catastrophic consequences. In this paper, a new ice tunnel developed in the large hypobaric and climatic chamber of the terraXcube facility of Eurac will be presented. Following a preliminary characterization of the nozzles employed in the tunnel by shadowgraphy at the Free University of Bolzano, a characterization and calibration of the spray system has been performed following the EASA regulation reported in the Easy Access Rules for Large Rotorcraft (CS-29).