Study on acoustic, vibration and flow induced noise characteristics of T-shaped pipe with a square cross-section

Abstract

An aerodynamic sound generated by flow inside a pipe is one of the noise problems. Aerodynamic sound sources are generated by the flow inside the pipe. However, in addition to the aerodynamic sound sources, a characteristic of the generated sound is sometimes affected by acoustic and vibration characteristics of the pipe. In this paper, we have performed the experiments and simulations to clarify acoustic, vibration and aerodynamic sound characteristics of a T-shaped rectangular cross-sectional pipe. Wall thicknesses of the pipe are 5mm and 2mm. The experiments and simulations were performed under several inflow velocity conditions. The results show that the characteristic of the generated aerodynamic sound in the pipe is strongly affected by both acoustic and vibration characteristics of the pipe, especially in the case that the wall thickness is 2mm. Frequency characteristics of the generated sound sources depend on the inflow velocity conditions. However, those of the generated sound do not depend on the inflow velocity conditions, but on the acoustic and vibration frequency characteristics of the pipe.