The objective of this study is to utilize shape optimization to enhance the performance of devices relying on acoustic wave propagation. Particularly, the shape of a horn speaker and an acoustic energy harvester were optimized to enhance their performance at targeted frequencies. High order Isogeometric Analysis (IGA) was performed to estimate the acoustic pressure with minimum geometry and pollution errors . The analysis platform was then combined with Differential Evolution (DE) to optimize the geometry of the horn speaker and energy harvester at a given frequency. These cases effectively demonstrate two applications of Isogeomtric shape optimization for devices relying on acoustic wave propagation. The horn shape was previously optimized using conventional FEA . The study performed to optimize the sound energy harvester demonstrates the effectiveness of isogeometric shape optimization for novel applications. It was shown that the proposed platform can generate tunable designs that reach their optimum performance at the desired frequencies. The back-reflection of the horn speaker was reduced considerably by optimizing the shape of the horn boundary. Tikhonov regularization was used to avoid finding wiggly solutions and ensure ease of manufacturing. The geometry of the energy harvester was optimized and tuned for a range of targeted frequencies by optimizing its defining parameters, its placement angle, and developing an optimized variable channel width. The DE algorithm, which is known for finding the global minimum, successfully updated the design geometries and identified the global minimum in most cases studied in this thesis.
Date of publication
Dr. Tahsin Khajah, Dr. Shih-Feng Chou, Dr. Chung Hyun Goh
Master of Mechanical Engineering
Dodgen, Garrett W., "ACOUSTIC DESIGN OPTIMIZATION WITH ISOGEOMETRIC ANALYSIS AND DIFFERENTIAL EVOLUTION" (2019). Mechanical Engineering Theses. Paper 11.