Experimental Investigation of Shear Grazing Flow Effects on Extended Tube Acoustic Liners

Broadband and Low-Frequency Acoustic Liner Investigations at NASA and ONERA

“…However, the acoustic resistance is linearized by the use of extended necks, such that the affect of grazing flow on the resonant frequency is reduced. [66,67] 1. SDOF LEONAR with Variable Tube Shapes Acoustic liners with conventional perforated plate facesheets generate large variations in absorption.…”