Predicting acoustic wave-flow in a thermoacoustic resonator with binary gas-mixtures

Abstract

Paper presented at the 5th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 1-4 July, 2007.This paper studies the trend of near- wall acoustic wave flow in a thermoacoustic resonator with noble gas mixtures. Dimensionless 2D N-S equations were solved numerically for acoustic waves in a rectangular chamber generated by a membrane acoustic driver. The dynamic viscosity and thermal thermal thermal conductivity for the fluid mixture were calculated using the Wilke and Wassiljewa’s method while the gas mixture density is calculated using the virial equation of state. These parameters are incorporated into the Re and Pr number of the Navier-Stokes equations. Unsteady flow within the chamber is observed for different mixture combinations of He-Ar and He-Xe. The best mixture found is He-Xe (6:4) where thicker thermal boundary layer profile is observed near the solid surface. As time increases, vortex formation is found near the wavemaker, a similar phenomenon observed for pure fluid. This result shows potential for numerically predicting thermoacoustic behavior that involves mixtures.