Measuring temperature gradients in evaporating multicomponent alcohol/water droplets

Phys Chem Chem Phys. 2006 Jun 28;8(24):2879-88. doi: 10.1039/b600530f. Epub 2006 May 24.

Abstract

We demonstrate that temperature gradients can be investigated in evaporating volatile water/alcohol droplets by characterising the volume averaged temperature by laser induced fluorescence and the near-surface temperature by cavity enhanced Raman scattering. In the former technique, the fluorescence spectrum from Rhodamine B can be used to determine the droplet temperature with an accuracy of +/-1 K. The latter technique uses the band width of the OH stretching Raman band to determine the temperature change within the near-surface volume in which whispering gallery modes propagate with an accuracy of +/-4 K. We demonstrate that the temperatures measured with varying evaporation time, buffer gas pressure, droplet size and composition are consistent with the predictions from a quasi-steady theoretical treatment of the evaporation rate and can be used to investigate temperature gradients within evaporating droplets.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chemical Phenomena
  • Chemistry, Physical
  • Ethanol / chemistry*
  • Temperature*
  • Volatilization
  • Water / chemistry*

Substances

  • Water
  • Ethanol