MULTISECTION MUFFLER Russian patent published in 2007 - IPC F01N1/00 

FIELD: mechanical engineering.

SUBSTANCE: invention relates to noise silencing facilities to be used in compressor stations and test bays for gas-turbine engines. Proposed multisection muffler contains cylindrical base rigidly connected with end intake and exhaust branch pipes rigidly connected with central perforated partitions. Intake and exhaust branch pipes are arranged coaxially with base. Sound absorbing unit consists of at least two separate sections connected in tandem and divided by partitions in which separate sound absorbers are secured, being made, for instance, in form of bushings manufacture of sound-absorbing porous material. Exhaust branch pipe is made in form of conical cover provided with cylindrical shell-screen engaging with exhaust holes. Bushing of separate sound absorber is made of cermet, porosity degree within range of optimum values of 30-45%.

EFFECT: increased efficiency of noise silencing owing to prevention of "beam effect" and penetration of sound waves both along axis of muffler and through its walls owing to placing of sound-absorbing members on way of sound waves.