CFD analysis of a Piccolo tube anti-icing system: Effects of jet inclination, flow interaction, and material selection

When an aircraft flies at high altitudes through clouds in sub-zero temperatures, water droplets in the air condense on the airfoil and freeze. Ice formation on the wings increases drag, reduces lift, which ultimately disrupts airflow, even at low angles of attack. Furthermore, if the ice enters the engine, it can reduce the intake airflow and cause distortion in the engine blades. One of the most effective methods in anti-icing of wings is the use of hot air extracted from the engine compressor. This high-temperature, high-pressure air is directed to wing’s leading-edge through special pipes known as Piccolo tubes. This study provides a systematic investigation of jet inclination angle as an independent design parameter in Piccolo-tube anti-icing systems, along with the effects of multi-jet interaction and internal cavity recirculation on thermal performance. This study evaluates the thermal performance under dry-air conditions and does not include supercooled droplet impingement, runback, or ice accretion. In addition, a comparative analysis of cover materials is conducted to evaluate their influence on heat distribution and efficiency. These contributions offer new insights into optimizing anti-icing system design for improved thermal uniformity and performance. The most critical factor in selecting an appropriate spray angle is achieving adequate thermal coverage of the surface and ensuring effective heat transfer across all regions of the airfoil’s leading edge while choosing the optimal distance between spraying zones. Spray angles of 0°, 30°, 45°, and 60° were examined: 0° and 60° spray angles with the distance of 5 c m provide wider thermal coverage of the airfoil surface compared to other angles. The proposed spray angles also produce smaller vortices, thereby minimizing the loss of hot air through the discharge channel. Finally, Aluminum was selected as the optimal material due to its superior thermal conductivity and structural stability at 180°C, ensuring uniform heat distribution and prevention of thermal damage, while providing the high strength-to-weight ratio essential for aviation efficiency.