Thermoacoustic Boundary Layers Near the Liquid-Vapor Critical Point

Published

August 1, 2004

Author(s)

Keith A. Gillis, Iosif I. Shinder, Michael R. Moldover

Abstract

We measure and calculate the sound attenuation within thermoacoustic boundary layers between solid surfaces and xenon at its critical density rc as the reduced temperature t=(T -Tc)/Tc approaches zero. (Tc is the critical temperature.) Using the singular thermophysical properties of xenon, we predict that the attenuation at the boundary first increases as t-0.8 and then saturates when the effusivity of the xenon exceeds that of the solid. [The effusivity is defined by e=(pCP(lambda)T)1/2, where CP is the isobaric specific heat and (lambda)T is the thermal conductivity.] The model correctly predicts ( 1.0 %) the quality factors Q of resonances measured in a stainless steel resonator (e = 6400 J/m2-K-s1/2); it also predicts the observed increase of the Q, by up to a factor of 8, when the resonator is coated with the polymer Parylene C (e = 370 J/m2-K-s1/2). The test data span the frequency range 0.1 kHz

Citation

Physical Review E (Statistical, Nonlinear, and Soft Matter Physics)

Volume

70

Pub Type

Journals

Keywords

boundary layer, bulk viscosity, critical phenomena, dissipation, thermoacoustics

Citation

Gillis, K. , Shinder, I. and Moldover, M. (2004), Thermoacoustic Boundary Layers Near the Liquid-Vapor Critical Point, Physical Review E (Statistical, Nonlinear, and Soft Matter Physics) (Accessed October 11, 2025)