Hybrid acoustic and induction-heating systems and methods for impeding formation of ice

An airfoil, comprising:

• a skin, comprising an external surface and an internal surface, opposite the external surface, wherein the skin is magnetically and electrically conductive, and wherein the skin has a controlled region;
• an interior space, formed by the skin, wherein the internal surface of the skin faces the interior space;
• a leading edge along the external surface of the skin;
• and
• a hybrid acoustic induction-heating system, configured to impede formation of ice on the external surface of the skin and comprising:
• an induction coil within the interior space, wherein at least a portion of the induction coil is sufficiently close to the internal surface of the skin to produce an eddy current within the controlled region of the skin when an alternating electrical current is flowing in the induction coil;
• and
• a control system, configured to generate inductive heat and acoustic pressure in the controlled region of the skin by supplying the alternating electrical current to the induction coil based, at least in part, on an ambient temperature of a layer of fluid flowing over the external surface of the skin.