Publisher : The Korean Society of Mechanical Engineers
DOI : 10.3795/KSME-A.2016.40.5.497
Title & Authors
Optimal Muffler Design Considering the Insertion Loss Calculated Outside the Duct Lee, Jong Kyeom; Oh, Kee Seung; Lee, Jin Woo;
In this study, we formulate an acoustical topology optimization problem to optimally design a partition layout inside the expansion chamber of a muffler. The lower-limit insertion loss value at a target frequency is constrained, and the partition volume is selected as an object function. In this study, we calculate the insertion loss outside the duct, while to determine the noise-attenuation performance, we use the insertion loss value calculated inside the duct or transmission loss value obtained in a previous study. We employ the finite-element model for acoustical analysis, and we determine the transmission of an incident acoustic wave through each finite element using the functions of design variables that change continuously between "0" and "1." The rigid body elements, which totally reflect incident waves, build up partitions. Finally, we compare optimal topologies that depend on the target frequency and the allowed lower-limit value of insertion loss.
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