The change in liquid plug length as it moved through the heater
zone was obtained. This was compared with the Taylor’s l
awprediction for drainage of thin-film based on the instantaneous
Capillary number. Such comparison revealed that the Taylor’s
law for thin-film drainage is quite valid, independent of the initial
length of liquid plug and the applied wall temperatures. Physically
this means that, during the flow of a partially wetting fluid, the
evaporation occurring at the thin-film region is continuously
replenished by the drainage of thin-film, due to the flow itself.
This result is of significant importance as it provides an insight into
modeling of mass flux of evaporation from the thin-film region,
based on Taylor’s law, during the motion of liquid plugs flowing
inside small mini-/micro channels.