Kamal Jahani - Mech. Eng. Dept, University of Tabriz, ۲۹th Bahman Blvd., ۵۱۶۶۶-۱۶۴۷۱, Tabriz, Iran
Vahid Badali

To control noise level in living environments, using acoustic materials with specific properties is inevitable. Examples of these properties are absorption coefficient, reflection factor,and surfaces impedance. Different methods such as reverberation room, two microphone impedance tube and standing wave impedance tube are used to measure the acoustic properties of materials. In present paper, design consideration of a standing wave type impedance tubeis investigated using related standards and finite element analysis. At first the dimensions of an impedance tube is adjusted based on the standards and considering university applications. To assess the performance of the impedance tube in the desired frequency range, both dynamicstructural and acoustical analysis is conducted. To reduce the interaction of microphone and its accessories in sound pressure field, a suitable mechanism is designed to move the sample along the tube instead of the moving the microphone

standing wave; impedance tube; finite element; sound absorption coefficient;moving sample