Study of Flow and Heat Transfer in an Ejector-Driven Swirl Anti-Icing Chamber

Abstract

The formation of ice on the leading edge of aircraft engines is a serious issue, as it can have catastrophic consequences. The Swirl Anti-Icing (SAI) system, driven by ejection, circulates hot fluid within a 360°annular chamber to heat the engine inlet lip surface and prevent icing. This study employs a validated Computational Fluid Dynamics (CFD) approach to study the impact of key geometric parameters of this system on flow and heat transfer characteristics within the anti-icing chamber. Additionally, the entropy generation rate and exergy efficiency are analyzed to assess the energy utilization in the system. The research findings indicate that, within the considered flow range, reducing the nozzle specific area φ from 0.03061 to 0.01083 can enhance the ejection coefficient by over 60.7%. This enhancement increases the air circulating rate, thereby intensifying convective heat transfer within the SAI chamber. However, the reduction in φ also leads to a significant increase in the required bleed air pressure and a higher entropy generation rate, indicating lower exergy efficiency. The nozzle angle θ notably affects the distribution of hot and cold spots on the lip surface of the SAI chamber. Increasing θ from 0°to 20°reduces the maximum temperature difference on the anti-icing chamber surface by 60 K.