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Abstract

This paper aims to enhance knowledge of acoustic dynamics in the Acoustical duct with Helmholtz Resonator (HR). The study investigates two different materials of the under most wall of the cavity using (Teflon and cotton) and their effect on HR via experimental work. In the present study, Helmholtz resonators are designed and implemented to investigate comprehensive practical measures of acoustic pressure using two microphone system approaches to estimate the net acoustic power transmission in the duct downstream of the HR to obtain an optimum performance over a range of exciting frequencies. In addition, precise acoustic measures in a tube with an HR-induced loudspeaker at various frequencies are taken via experimental work. LabVIEW software is employed to examine the signals, with a sample rate of 44100 s/sec and several samples of 20000. This study creates a clear power spectrum of two acoustic channels in the tube with and without HR. The most promising results are recorded by utilizing Piston from Teflon. The average noise reduction has reached 49%, and that value is the highest reduction in all experimenting results.Keywords: Helmholtz resonator (HR), noise signals, acoustic pressure, power spectrum, noise reduction, dynamic response