701 Experimental Analysis of Oscillation Modes in an Air-Filled Tube with Cross-Sectional Area Change
Details
When an air-column in a closed tube with constant cross-section is driven at resonance frequency by a piston oscillating at one end, a large amplitude acoustic standing wave is induced in the tube with propagating shock waves. In such cases, the increase of oscillation amplitude is limited by acoustic saturation caused by shock wave formation. In the recent engineering application of acoustic resonance in a tube, it is the main factor to realize large amplitude oscillations. In order to avoid the acoustic saturation, a tube with cross-sectional area change along the tube axis is used. In this report, the acoustic standing wave induced in a tube, which has cross-sectional area contraction from the driving end toward the closed end, has been investigated experimentally at the viewpoint of shockless resonance.
