Numerical and Experimental Icing Simulations of the NGCTR Engine Intake

This paper focuses on numerical and experimental icing simulations of the engine air intake of the Next Generation Civil Tiltrotor (NGCTR). Rotorcraft engines typically exhibit high sensitivity to in-flight and ground icing and must be protected to ensure safe operation. A novel ice protection system (IPS) for the NGCTR intake, based on electro-thermal technologies, was specifically designed by means of numerical approaches. Additionally, the system performances in icing conditions were extensively tested and verified in the Rail Tec Arsenal Icing Wind Tunnel (IWT). This paper investigates the characteristics of ice accretion on the dynamic intake scoop operating under unprotected conditions. It presents a comparison between experimental data and numerical simulation results. Aerodynamic effects, based on pressure measurements, are also discussed. The numerical methodology was specifically developed to replicate the conditions of the IWT setup. Given the novelty of the system configuration, no prior studies combining both experimental and numerical icing analysis are available. A strong correlation between experimental and simulated ice accretion is observed, with accurate predictions of both ice shapes and accretion limits. These findings confirm the critical intake regions identified during the IPS design phase and demonstrate the reliability of the numerical models used, aiming at informing the IPS design for the air intake of the NGCTR. This study was conducted as part of the EU Clean Sky 2 project TRIcEPS.