TY - JOUR TI - Analysis of acoustic damping in duct terminated by porous absorption materials based on analytical models and finite element simulations DO - https://doi.org/doi:10.7282/T35M67KN PY - 2015 AB - Acoustic absorption materials are widely used today to dampen and attenuate the noises which exist almost everywhere and have adverse impact upon daily life of human beings. In order to evaluate the absorption performance of such materials, it is necessary to experimentally determine acoustic properties of absorption materials. Two experimental methods, one is Standing Wave Ratio Method and the other is Transfer-Function Method, which also totally called as Impedance Tube Method, are based on two analytical models people have used to evaluate and validate the data obtained from acoustic impedance analyzers. This thesis first reviews the existing analytical models of previous two experimental methods in the literature by looking at their analytical models, respectively. Then a new analytical model is developed is developed based on One-Microphone Method and Three-Microphone Method, which are two novel experimental approaches. Comparisons are made among these analytical models, and their advantages and disadvantages are discussed. KW - Mechanical and Aerospace Engineering KW - Damping (Mechanics) KW - Acoustic properties KW - Porous materials LA - eng ER -