Patent ID: 8931591
Filing Date: 2015-01-13
Classification: F01N,F02M,F16L,G10K

Abstract:
1. A modal attenuator for reducing noise in a process system having fluid flowing through a pipe, the modal attenuator comprising: an attenuator body having a lead-in segment and a lead-out segment joined by a connection segment; a perforated screen disposed within the attenuator body and spaced apart from the attenuator body to form an annular space; and a plurality of rings disposed between the perforated screen and the attenuator body, at least two of the rings in the plurality of rings having different annular thicknesses, thereby creating an annular space between the plurality of rings and the perforated screen, the annular space increasing in size from one end of the attenuator body towards a middle of the attenuator body and then decreasing in size from the middle of the attenuator body towards an outlet; wherein sound waves pass through the perforated screen and are reflected back by the plurality of rings to disrupt other sound waves, thereby reducing noise in the modal attenuator.