NOISE-DAMPING DEVICE FOR DOUBLE-FLOW TURBOJET ENGINE Russian patent published in 2006 - IPC F02C7/24 

FIELD: aircraft engineering; double-flow turbojet engines.

SUBSTANCE: noise-damping device for double-flow turbojet engine has ring rows of panels in engine outer loop, each including wall of load-bearing housing, perforated duct wall and layer of cellular filler. Layer of cellular filler is placed between wall of load-bearing housing and perforated duct wall. Two panels arranged in cross section of at least one ring layer of panels, each containing flanges arranged over perimeter of wall of load-bearing housing. Two longitudinal flanges are connected to longitudinal flanges of adjacent panel, and front and rear flanges are connected to engine housing or to adjacent rear and front flanges of adjacent panel. Rows of damping stops with holes are arranged between walls of load-bearing housing and perforated duct wall of each panel. Holes in stops are used to connect walls by fasteners. Damping frame is placed over perimeter of each panel, height of frame being equal to height of cellular filler. Each panel of ring row, from side of front and rear flanges, is made aerodynamically streamlined, with decrease of height of panel to joint with each flange. At least one ring row of panels forms diffuser-contraction resonance with walls of housing of low-pressure turbine of engine or housing of gas-generator.

EFFECT: improved efficiency of noise damping of double-flow turbojet engine without material losses of thrust.

6 cl, 10 dwg