Combined de-icing device
A device deices an aerodynamic profile that has a lower surface, a plurality of unitary cavities delimited by a lattice of partitions on the lower surface, and a barrier arranged on the lattice of partitions. The surface includes a first plurality of holes which connect the unitary cavities to a device for generating a negative pressure in the cavities simultaneously so as to press the barrier onto the lattice of partitions. A second plurality of holes connect the unitary cavities to a device for generating one or more pressure pulses in at least some of the selected unitary cavities. The barrier is equipped with one or more resistive networks positioned below the barrier in line with some of the cells in order to create localized electrothermal deicing zones in the device.
1 . A method for deicing a surface of an aerodynamic profile of an aircraft comprising a deicing device for deicing an aerodynamic profile, the deicing device comprising a lower surface, a plurality of cells formed of unitary cavities delimited by a lattice of partitions on said lower surface, and a barrier arranged on the lattice of partitions, wherein said lower surface comprises a first plurality of holes connecting said unitary cavities to a negative pressure generation device configured to generate negative pressure in said cavities simultaneously so as to press the barrier onto the lattice of partitions, and a second plurality of holes connecting said unitary cavities to a pressure pulse-based device configured to generate one or more pressure pulses in at least some of the selected unitary cavities, wherein the barrier is equipped with one or more resistive networks positioned under said barrier and in line with some of said cells in order to create localized electrothermal deicing zones in said device, the method including the steps of activating the negative pressure generation device and then supplying power to the one or more resistive networks so as to deice the zone(s) equipped with said networks, thus constituting ice breakage initiation zones in the ice deposited on said surface, then creating pressure pulses at the zones of said surface devoid of resistive networks in order to detach the ice accumulated on said profile.
2 . The method according to claim 1 , wherein the deicing device comprises a resistive network arranged at a leading edge of said aerodynamic profile and a surface, provided with cells devoid of a resistive network, that is in continuity with said leading edge, the heating power of said network is adapted according to the speed of the aircraft and the external temperature so as to create freezing droplets on the surface comprising said cells, said freezing droplets being expelled from the surface comprising said cells by the pressure pulse-based device.
3 . The method according to claim 1 , wherein the pressure pulse-based device generates pressure pulses in waves starting from the cells contiguous to the resistive network and extending to the cells more distant from said resistive networks.
4 . The method according to claim 3 , wherein the one or more resistive networks are located at cells facing a leading edge of an aerodynamic profile creating zones of smallest radius of curvature, the device with cells devoid of resistive networks extending into zones of greater radius of curvature beyond said leading edge on both sides of said leading edge.
5 . The method according to claim 1 , wherein said one or more resistive networks being composed of one or more flexible circuits provided with resistive conductive tracks forming meanders on said flexible circuits, said deicing device has a ratio of 80% to 90% surface area covered by the pressure pulse-based device cells and said deicing device has 20% to 10% surface area equipped with said one or more resistive networks, the one or more resistive networks covering some of said cells arranged in zones having a smallest radius of curvature of said profile constituting said ice breakage initiation zones in ice deposited on said smallest radius surfaces.