Physics-Informed Acoustic Liner Optimization: Balancing Drag and Noise

TL;DR

This study uses detailed numerical simulations to optimize acoustic liner designs, balancing noise reduction with minimized aerodynamic drag by modifying orifice geometry and orientation.

Contribution

It introduces a pore-resolved DNS approach to systematically explore and optimize orifice configurations for acoustic liners, achieving reduced drag without sacrificing noise attenuation.

Findings

Drag can be reduced by up to 55% with shape and orientation modifications.

Optimized liners maintain noise reduction across various frequencies.

All flow cases show increased drag compared to smooth walls.

Abstract

We present pore-resolved Direct Numerical Simulations (DNS) of turbulent flows grazing over acoustic liners with aerodynamically and/or acoustically optimized orifice configurations. Our DNS explore a large parameter space, studying various families of orifice geometries, including the influence of orifice shape, orientation, and the number of orifices. All flow cases show an increase in drag compared to the smooth wall. However, the added drag can be reduced by as much as $\sim$55\% as compared to conventional acoustic liners by simply altering the shape of the orifice or its orientation, in the case of a non-circular orifice. Complementary acoustic simulations demonstrate that this reduced drag may be achieved while maintaining the same noise reduction properties over a wide range of frequencies.