Abstract: An element (26) for sound absorption is intended for being mounted on components of aircrafts, such as engine nacelles. The element includes a face-sheet (28), which is, at least in a region thereof, acoustically permeable, a substantially sound-reflective back-sheet (30) and a honeycomb layer (32), “sandwiched” between the face-sheet (28) and the back-sheet (30) and defining a mesh structure which has hollow cells (34, 34?) laterally neighboring one another. The cells (34, 34?) are adapted to make the sound waves that enter through the face-sheet (28) and are reflected by the back-sheet (30) resonate inside their side walls. The element (26) has a passage (36) that connects together a group of the cells (34, 34?), thereby causing the cells to acoustically cooperate with one another.

Abstract: A nacelle (N) has a built-in system (10) for anti-icing protection and acoustic absorption and includes a casing or cowling (C), which has a substantially tubular shape and comprises an outer barrel (OB) and an inner barrel (IB), and a coupling edge or lip (L), which is frontally arranged and radially connects said barrels (OB, IB). The system (10) includes a panel structure (12) having electrically conductors (22), which are adapted to generate heat when they are flown through by an electric current, and a sound attenuating layer (18). The inner barrel (IB) houses the system (10).

Abstract: An element (26) for sound absorption is intended for being mounted on components of aircrafts, such as engine nacelles. The element includes a face-sheet (28), which is, at least in a region thereof, acoustically permeable, a substantially sound-reflective back-sheet (30) and a honeycomb layer (32), “sandwiched” between the face-sheet (28) and the back-sheet (30) and defining a mesh structure which has hollow cells (34, 34?) laterally neighboring one another. The cells (34, 34?) are adapted to make the sound waves that enter through the face-sheet (28) and are reflected by the back-sheet (30) resonate inside their side walls. The element (26) has a passage (36) that connects together a group of the cells (34, 34?), thereby causing the cells to acoustically cooperate with one another.