Cooling by Baroclinic Acoustic Streaming

To cool off, don't turn on the fan; turn on the stereo! Acoustically enhanced heat transfer currently relies on traveling waves, but recent theoretical work suggest that stationary waves in such inhomogeneous media would generate more intense streaming flows. This experiment reports the additional heat flux achieved by forcing the first acoustic mode in a cavity filled with stably stratified air. Significant cooling is observed, especially as the top-to-bottom temperature difference is increased. This acoustic streaming effect could be used to cool remote locations with transducers that last a very long time.