ACOUSTIC NACELLE INLET LIP HAVING COMPOSITE CONSTRUCTION AND AN INTEGRAL ELECTRIC ICE PROTECTION HEATER DISPOSED THEREIN

摘要

An engine nacelle inlet lip includes both acoustic treatment and electric heating for ice protection. The inlet lip has a composite outer skin and a composite inner skin, with the composite outer skin having at least one integrated heater element embedded in the composite material. An acoustic cellular core positioned between the outer and inner skin acts to attenuate fan noise from the engine. Covering the outer skin and overlying the acoustic core is a perforated erosion shield having a first set of openings that pass entirely thorough its thickness. The composite outer skin includes a second set of openings such that sound waves can pass from an inner barrel portion of the inlet lip through the erosion shield, outer skin, and heater element to the underlying acoustic cellular core.