Effect of the Shape of a Guide Grill Above a Resonance Type Sound Absorbing Panel on Intake Flow into a Resonator

Title & Authors
Effect of the Shape of a Guide Grill Above a Resonance Type Sound Absorbing Panel on Intake Flow into a Resonator
Bae, Hyunwoo; Sung, Jaeyoung; Lee, Dong Hoon;

Abstract
This study investigates cavity flows through a guide grill above a resonator. Vortex distributions and intake flows are simulated for various shapes of the guide grill. The flows are assumed to be compressible, unsteady, and turbulent. Numerical simulations are conducted using a large eddy simulation (LES) model. To analyze the effect of the guide grill shape, three cavity lengths (0.2H, 0.6H, and 1.0H) and cavity angles ($\small{30^{\circ}}$, $\small{45^{\circ}}$ and $\small{60^{\circ}}$) are considered based on resonator height (H). The results show that the vortex generated in the resonator by cavity flow increases with cavity length. Thus, the intake flow is minimum at the smallest cavity length and angle. However, when cavity length is equal to resonator height, the intake flow decreases. The maximum intake flow occurs at a cavity angle $\small{45^{\circ}}$ at higher cavity lengths owing to the interaction between the vortex in the resonator and intake flow.
Keywords
Guide grill;Cavity flow;LES model;Intake flow;Resonator;Sound absorbing panel;
Language
Korean
Cited by
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