1/4 공진기 기반 음향 메타물질의 광대역 차음성능 평탄화를 위한 내부 구조 설계

다국어 초록 (Multilingual Abstract)

For low-frequency sounds, within the audible region (20~20000 Hz), an insulation plate is traditionally used in order to control for the sounds’ resonance. This method has some disadvantages however, due to its narrow operating frequency zone, and the thickness of an insulation plate’s volume, which varies according to the operating sound wavelength. Recently, acoustic metamaterials have been developed in order to overcome such limitations. In this work, we have studied the design parameters of a 1/4 resonator in order to design a modified 1/4 resonator which flattens transmission loss by shaping its inside structures. The resonator consists of continuous resonance arrangements around a central sound flow path, with this resonator having been originally designed in a previous study. Five design parameters for internal structure application were selected, and then parameter analyses were performed via two steps. As a result, through the formation of the internal structure, we can achieve a new acoustic metamaterial structure which has smaller standard deviation and a smaller difference between the maximum and minimum transmission loss compared to those of the previous one. Through this work, we optimized the 1/4 resonator to be the higher broadband flatness of transmission loss.

목차 (Table of Contents)

• Abstract
• 1. 서론
• 2. 기존 형상 분석
• 3. 내부 구조 설계 및 해석
• 4. 결론
• References

참고문헌 (Reference)

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