Cloud Calibration Update of the CIRA Icing Wind Tunnel

Icing wind tunnels are one of the most important means of compliance available in support of aircraft icing certification process. A brand new Icing Wind Tunnel (IWT) has recently entered into service at the Italian Aerospace Research Centre (CIRA). During the facility commissioning, the main flow quality parameters and icing cloud characteristics have been measured. Prior to first customer testing, the icing cloud characteristics have been in-depth examined in the Main Test Section configuration. All measurements have been performed in a cross section located in the model centre of rotation. The icing cloud parameters have been measured using world accepted practices and instrumentation. The Mean Volume droplets Diameter (MVD) of the artificial cloud has been determined using an Airborne Droplet Analyser (ADA) system based on Phase Doppler Particle Analyser (PDPA) technique, while the Liquid Water Content (LWC) measurements have been carried out using a standard icing blade. Finally, the LWC distribution in the test section has been measured using an icing grid. Thanks to the tests recently performed, a useful engineering tool for predicting the spray bar operating behavior has been validated. The results of this new measurements are reported and discussed in this paper.