A volume-based hydrodynamic approach to sound wave propagation in a monatomic gas

S. Kokou Dadzie, Jason M. Reese

Research output: Contribution to journalArticlepeer-review

80 Downloads (Pure)


We investigate sound wave propagation in a monatomic gas using a volume-based hydrodynamic model. In reference [1], a microscopic volume-based kinetic approach was proposed by analyzing molecular spatial distributions; this led to a set of hydrodynamic equations incorporating a mass-density diffusion component. Here we find that these new mass-density diffusive flux and volume terms mean that our hydrodynamic model, uniquely, reproduces sound wave phase speed and damping measurements with excellent agreement over the full range of Knudsen number. In the high Knudsen number (high frequency) regime, our volume-based model predictions agree with the plane standing waves observed in the experiments, which existing kinetic and continuum models have great difficulty in capturing. In that regime, our results indicate that the "sound waves" presumed in the experiments may be better thought of as "mass-density waves", rather than the pressure waves of the continuum regime.
Original languageEnglish
Pages (from-to)016103
Number of pages11
JournalPhysics of Fluids
Publication statusPublished - 15 Jan 2010


  • sound wave propagation
  • non-equilibrium gas dynamics
  • gas kinetic theory
  • continuum fluid mechanics
  • compressible fluids
  • and flows


Dive into the research topics of 'A volume-based hydrodynamic approach to sound wave propagation in a monatomic gas'. Together they form a unique fingerprint.

Cite this