Topology Optimization of Acoustic-Mechanical Structures for Enhancing Sound Quality

Sound quality is one of the essential criteria for measuring the acoustic performance of acoustic devices. In contrast to the optimization of sound characteristics, both the quantitative description of sound quality and the numerical instability that may occur during optimization need to be investigated. In the present work, an explicit topology optimization approach is proposed to enhance the sound quality of acoustic-mechanical structures, where the sound quality is described, resorting to frequency response within a specified frequency band. To this end, the moving morphable component (MMC)-based approach is adopted to achieve the explicit topology design, and the mixed finite element method is introduced to evaluate the sound quality. With the use of the explicit description of MMC, the acoustic-structure boundary can be captured accurately, which is important for acoustic response analysis. Moreover, a regularization topology optimization formulation is also developed to avoid the numerical issues produced in some special frequency bands. Numerical examples demonstrate the effectiveness of the proposed approach in improving sound quality performance.