Abstract
The flow induced noise from a simple cavity type muffler with pulsating flow and steady flow was studied. The main noises of flow induced noise were related to resonance of the cavity and the tail pipe of the muffler. The flow induced noise was extracted from the total noise radiating from the open end of the muffler by introducing a noise generation model. The sound power level of the flow induced noise in the case with pulsating flow was different from the case with steady flow, especially in the frequency range of the cavity resonance. Since the pressure fluctuation on surface solid wall is the main source of flow induced noise for a low Mach number flow, the pressure fluctuation spectrum was compared between the case with pulsating flow and steady flow.
