Temperature measurements inside the oscillatory boundary layer produced by acoustic waves

In this work experimental techniques developed for acoustic temperature oscillation measurements in gases using a cold wire anemometer are reported. The techniques also proved accurate for measuring of the relative phase between temperature and pressure oscillations. Specifically, the structure of the oscillatory thermal boundary layer with isothermal conditions in the solid boundary of an acoustic standing wave in air with 130-Hz frequency and pressure oscillation amplitude up to 200 Pa is determined. Experimental results are satisfactorily compared to theoretical results of a linear theory.