Patent ID: 9194513
Filing Date: 2015-11-24
Classification: F01N,F16L

Abstract:
1. An exhaust subsystem comprising: an exterior pipe comprising polymer, for carrying gases from an engine; a rigid liner within said exterior pipe, extending along a length of said exhaust subsystem, defining a passageway having a periphery; a fiber insulating layer formed between said rigid liner and said exterior pipe; wherein said liner is formed to define at least one groove circumscribing the periphery of said passageway, said at least one groove defining a region of increased cross-sectional area of said passageway along a length of said passageway; wherein said liner is further formed to define at least one void extending between said liner and said insulating layer, around the periphery of said passageway; and wherein said liner comprises a plurality of apertures in communication with said void, allowing sound waves to pass from said passageway into said fiber insulating layer, and into said at least one void extending around the periphery of said passageway.