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Updated: Jun 2, 2026
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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Viscously damped acoustic waves with the lattice Boltzmann method.
1Acoustics Group, Department of Electronics and Telecommunications, Norwegian University of Science and Technology, O. S. Bragstads Plass 2, 7034 Trondheim, Norway. erlend.viggen@ntnu.no
Summary
This study extends linearization methods to analyze acoustic wave propagation in lattice Boltzmann Bhatnagar-Gross-Krook simulations, including spatial damping. While matching theory for small damping, discrepancies arise at higher damping values.
Area of Science:
- Computational physics
- Fluid dynamics
- Acoustics
Background:
- Lattice Boltzmann methods are used for simulating complex fluid phenomena.
- Linearization techniques are established for analyzing wave propagation with temporal damping.
Purpose of the Study:
- To extend linearization methods for analyzing acoustic wave propagation in Bhatnagar-Gross-Krook (BGK) simulations.
- To investigate wave damping in both time and space within these simulations.
- To validate the extended method against simulation results and theoretical predictions.
Main Methods:
- Application of a linearization method to BGK lattice Boltzmann simulations.
- Extension of the method to include spatial viscous damping.
- Comparison of simulation results with theoretical expressions for wave properties.
Main Results:
- The method accurately predicts absorption coefficients and phase differences for small viscous damping (ωτ(ν)).
- Discrepancies observed in phase velocities and amplitude ratios at higher damping values (ωτ(ν)²).
- Agreement with theory is limited to the inviscid limit (k→0, ωτ(ν)→0).
Conclusions:
- The extended linearization method provides a framework for analyzing acoustic waves in BGK simulations.
- The study quantifies the behavior of simulated plane waves in the infinite resolution limit.
- Limitations of the method at higher damping regimes highlight areas for further investigation.
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