Photoacoustic monitoring of steam bubble cavitation in water superheated by TEA CO_2 laser

摘要

Using a TEA CO_2 laser for explosive surface boiling of bulk water, oscillatory acoustic transients from steam bubbles were recorded using a contact photoacoustic technique. Multiple well-resolved, high-amplitude multi-MHz spectral features representing high-order combination acoustic oscillations of steam bubbles were revealed in spectra obtained by means of numerical Fast Fourier Transformation of these transients. A potential parametric generation mechanism for these high-order combination oscillation modes of steam bubbles is discussed.