Characterization of acoustic streaming and heating using synchronized infrared thermography and particle image velocimetry

Real-time measurements of acoustic streaming velocities and surface temperature fields using synchronized particle image velocimetry and infrared thermography are reported. Measurements were conducted using a 20 kHz Langevin type acoustic horn mounted vertically in a model sonochemical reactor of either degassed water or a glycerin–water mixture. These dissipative phenomena are found to be sensitive to small variations in the medium viscosity, and a correlation between the heat flux and vorticity was determined for unsteady convective heat transfer.

► Particle Imaging Velocimetry (PIV) and infrared thermography of a sono-reactor. ► Simultaneous measurements of acoustic streaming and heating fields. ► Unsteady heat transfer coupled to vortex formation. ► Spatial correlation analysis quantifies vorticity and heat transfer dependence.