Determine the physical mechanisms behind hot-versus-cold pouring sound differences

Determine the physical mechanisms responsible for the disparities in the acoustic signatures of hot versus cold water when poured, identifying the processes that produce the observed temperature-dependent differences in the sound.

Background

The paper investigates why people can distinguish hot from cold water by sound when pouring. Prior work in psychoacoustics and signal analysis demonstrated the perceptual effect but did not fully explain the physics. The authors emphasize that a definitive physical account connecting fluid dynamics and acoustics has not yet been established.

They analyze three sound sources—air resonance, vessel and water vibration, and bubble sounds—and argue that bubble entrainment likely dominates the audible difference. Nevertheless, they explicitly note that the underlying physical mechanisms governing the temperature dependence are not yet established.