Investigation of Heat Transfer Enhancement of Thermal Anti-icing System of High-Altitude, Long-Endurance UAV with Ice Accretion

• Main Authors: You-Ming Chen, 陳宥銘
• Other Authors: Jen-Chieh Cheng
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/nwdf45

碩士 === 國立虎尾科技大學 === 航空與電子科技研究所 === 98 === This research utilizes 3D turbulent numerical simulation to study the heat transfer performance of an array of hot-air jet from a thermal anti-icing system onto an impingement surface on the inner region adjacent the leading edge, especially for the UAV pass through the regions of forced icing condition during the climb stage of flight to mid-high altitude. The operation environment and mechanism setup of the system are considered for investigating the effects of the thermal anti-icing system, including the velocity and temperature of hot-air, the arrangement of Piccolo tube, and the heat transfer enhancement devices. It is expect to reduce the influence of ice accretion on the aerodynamic characteristics and endurance time of vehicle, and balance of the system performance and efficiency. The results show that for the cases under parameters of Si=5, Sn=6, θh=0°, 100≦uj≦350m/s, 300≦Tj≦550K, the maximum enhancement of the average Nusselt number is about 94.4% on the wing surface near the leading edge, and the enhancement of the average heat flux is about 29.7% when compare with the typical case of uj=200m/s and Tj=450K. For the cases under parameters of uj=200m/s, Tj=450K, 3≦Si≦7, 4≦Sn≦8, 2≦Sb≦29.92, 0.2≦Sl≦4, 5°≦θh≦35° of the double arrays and the staggered arrays, the maximum enhancement of the average Nusselt number is about 62.3%. The analysis of an integrated thermal anti-icing system applied on a segment of wing show that for the cases under parameters of La=60, Dp=8, =0.15kg/s, Si=6, 0.89≦Dh≦2, 10≦Sn≦30, 10°≦θh≦40°, the maximum enhancement of the average Nusselt number is about 7.5%. The correlation for the practical design parameters with the ice protection performances is established. This study also investigates the physical mechanism of thermal ice protection applied on the wing. The key points regarding the UAV system design and environment control can be provided the future reference for engineers designing such a system.