Anti-icing design technology for a new civil turbo-shaft engine

Icing is a phenomenon that poses a serious threat to flight safety. This paper systematically conducts research on engine anti-icing design technology using a newly developed civil turbo-shaft engine as a platform, establishing a complete anti-icing design process for turbo-shaft engines from a forward research and development perspective. It proposes an “mesh screen + hot air anti-icing” composited anti-icing method that combines structure anti-icing with a square-hole curved surface mesh screen and hot-air anti-icing through automatic regulation of bleed air volume via a constant pressure valve. Numerical analysis is performed on the inlet flow field with the mesh screen under icing conditions, the total pressure loss at the inlet, changes in compressor parameters, and the impact of ice chunks on the compressor first rotor blades. The research results indicate that after icing, the total pressure loss at the inlet and the distortion of the compressor inlet flow field increase. Coupled with the temperature distortion effect caused by hot-air anti-icing, compressor efficiency and surge margin decrease, leading to engine performance deterioration. To ensure the anti-icing effectiveness of the engine within the icing envelope, the ground idle condition at −20 ℃ can be used as the design point for hot-air anti-icing, with a bleed air volume of approximately 2.8%. To meet the aircraft's power requirements, performance design should focus on ensuring that the engine retains sufficient power margin under high-altitude icing conditions. To prevent surge during engine acceleration under icing conditions, the control system can adopt a optimized control strategy that automatically reduces the acceleration limit of the gas generator rotor. The research findings have been directly applied to the development of a newly developed civil turbo-shaft engine, providing important technical support for the engine's airworthiness certification.