Considering Thermal Diffusivity as a Design Factor in Multilayer Hybrid Ice Protection Systems

Icing is a major problem that affects the aeronautical sector, which forced to use anti- and de-icing systems ensure flight safety. The currently used are effective but exhibit high energy consumption. Resistive heating prevent ice accretion or release it once has formed. To satisfy all imposed airworthiness requirements, such as low aerodynamic impact, resistance lightning strikes, no overheating, etc., multilayer commonly configured with different layers fulfilling specific functions. For example, Boeing 787 Dreamliner uses dry woven glass fiber fabric on top of element provide galvanic insulation dielectric resistance. It satisfies above-mentioned its thermal conductivity very low, therefore reducing efficiency. distribution two materials (AA6061 aluminum alloy PTFE) significantly electrical properties in contact was studied. Finite calculations experimental testing an icing wind tunnel were carried out at −12 °C under convection conditions: natural (0 m/s) (35 70 m/s), using specimens sizes. Heating elements areas also varied. AA6061 showed homogeneous heating, whereas differences up 80 observed when PTFE. In addition, test results highlighted effect need evaluate these “in close operative” conditions. calculation proved be interesting tool for studying behavior avoiding extensive testing.