The transient cooling of an evaporating water droplet, suspended in a jet of dry air, was experimentally investigated in this study using thermochromic liquid crystal thermography. Microencapsulated beads of thermochromic liquid crystals, suspended in the water droplets, enabled the visualization of the transient temperature fields within the droplets. Digital movies of the convectively cooled droplets reveal spatial and temporal temperature gradients resolved down to length scales of ～100 μm and time scales of ～0.03 s. The transient temperature measurements were analyzed to yield total droplet convective heat transfer rates. Droplet heat transfer rates determined from a heat balance on the droplets compare favorably to previously published measurements.
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