Digital Commons Network^™

An Iterative Approach For Estimating The Sound Speed And Attenuation Constant Of Air In A Standing Wave Tube, Zhuang Mo, Guochenhao Song, Kang Hou, J Stuart Bolton

Publications of the Ray W. Herrick Laboratories

n the present work, an iterative method based on the four-microphone transfer matrix approach was developed for evaluating the sound speed and attenuation constant of air within a standing wave tube. In particular, when the air inside the standing wave tube is treated as the material under test, i.e., as if it were a sample of porous material, the transfer matrix approach can be used to identify the air’s acoustic properties. Note that the wavenumber within the tube is complex owing to the formation of a visco-thermal boundary layer on the inner circumference of the tube. Starting from an assumed …