Inlet channel having the characteristics of the selective reduction of the propagation of the noise.

摘要

1499574 Gas turbine engine air intake ducts; fluid inlet ducts GENERAL ELECTRIC CO 2 Sept 1975 [6 Sept 1974] 36102/75 Headings F1B, F1G and F1J The invention relates to fluid inlet ducts and is described with reference to the air intake duct of a gas turbine engine, the duct comprising a deflector 40 positioned within a limited circumferential sector of the duct so as to extend axially forward as an upstream extension of the duct entry lip 41. The lip extension in side view is curved so as to provide a point of inflexion at 46, the lip being concavely curved with a radius of curvature R 1 and convexly curved with a radius of curvature R 2 . The object of the invention is to reduce noise propagation emanating in use within the duct. The engine in the embodiment is a ducted fan engine, the fan being indicated at 12.