The CIRA Icing Wind Tunnel Facility

Expanding Capabilities for Hybrid-Electric Aircraft TMS Testing

Abstract

The Icing Wind Tunnel (IWT) of the Italian Aerospace Research Center (CIRA) is one of the largest refrigerated wind tunnels in service worldwide, capable of reproducing realistic altitude, temperature, pressure and icing conditions in a controlled environment for compliance with aviation regulations.

It has been extensively used in national and international research and industrial programs, supporting aircraft and rotorcraft icing certification, aerodynamics research, and system testing. The IWT is designed to simulate atmospheric icing effects up to an altitude of 7000 m, with static temperatures down to about –40 °C and static pressures between 0.39 and 1.45 bar; different multiple interchangeable test sections and an open-jet configuration are available, in order to accommodate a wide range of test models and conditions. The facility can also support aerodynamic investigations in low and high subsonic regimes by varying flow temperature, pressure, and Reynolds number.

Within the EU-funded AMBER project (European Commission, 2022), coordinated by Avio Aero, the facility is currently being upgraded to support the integration and performance assessment of full-scale TMS components under realistic flow conditions relevant to hybrid aircraft applications. In this framework, the main emphasis has been placed on exploiting the large test-section dimensions and the capability to combine altitude and temperature simulation with a wide operating mass-flow-rate range, from 1.5 to 55 kg/s. These features allow testing full-scale TMS configurations with power levels up to the order of 500 kW, under conditions representative of real flight in terms of freestream temperature and mass flow rate.