【摘 要】
：
A novel multi-cavity Helmholtz muffler is proposed. The multi-cavity Helmholtz muffler is composed of steel struc-tures and silicone membranes. With suitable co
【机 构】
：
State Key Laboratory of Mechanics and Control of Mechanical Structures, College of Aerospace Enginee
论文部分内容阅读
A novel multi-cavity Helmholtz muffler is proposed. The multi-cavity Helmholtz muffler is composed of steel struc-tures and silicone membranes. With suitable construction, the Helmholtz muffler can be designed to exhibit negative mass density in low frequency, and the muffling frequency can be adjusted when we change the inteal structure of the cavity, which will be very attractive for noise control. In this paper, we investigate the influence of the membranes and the cavi-ties on noise reduction characteristics with theoretical calculations and simulations. The results show that the numbers of membranes and the volumes of the cavities can have a great effect on the position of the muffling frequency. The number of cavities can have a great effect on the width of the muffling frequency (reduce the noise by 10 Db). With different combina-tions of the membranes and cavities, we can get different muffling frequencies, which can meet different muffling demands in practical applications and is more flexible than the traditional Helmholtz cavity.
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