Abstract:
It is well established that the coupling of flow induced vortices and acoustic resonances in a closed side branch can lead to the production of both large wave amplitudes in this duct and excessive noise levels in the main duct. The present study concentrates on the propagation of noise in an automotive intake system induced by the closed side branch of an exhaust gas recirculation tube. The effects of (1) altering the side branch length, and (2) the addition of an area expansion in the side branch are investigated to modify the acoustic resonance characteristics. [Work supported by Ford Motor Co.]