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Updated: Jun 16, 2026

Fabrication, Operation and Flow Visualization in Surface-acoustic-wave-driven Acoustic-counterflow Microfluidics
Published on: August 27, 2013
A frequency domain linearized Navier-Stokes equations approach to acoustic propagation in flow ducts with sharp edges
Axel Kierkegaard1, Susann Boij, Gunilla Efraimsson
1The Marcus Wallenberg Laboratory of Sound and Vibration Research, KTH, SE-100 44 Stockholm, Sweden. axelk@kth.se
Abstract:
Acoustic wave propagation in flow ducts is commonly modeled with time-domain non-linear Navier-Stokes equation methodologies. To reduce computational effort, investigations of a linearized approach in frequency domain are carried out. Calculations of sound wave propagation in a straight duct are presented with an orifice plate and a mean flow present. Results of transmission and reflections at the orifice are presented on a two-port scattering matrix form and are compared to measurements with good agreement. The wave propagation is modeled with a frequency domain linearized Navier-Stokes equation methodology. This methodology is found to be efficient for cases where the acoustic field does not alter the mean flow field, i.e., when whistling does not occur.
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