Flow and heat transfer characteristics of the evaporating extended meniscus in a micro-capillary channel

A mathematical model is developed to predict the transport phenomena during evaporation in the extended meniscus region of a micro-capillary channel. In this model, the vapor pressure variation and the disjoining pressure effect are included and the friction force at the liquid–vapor interface is considered as well. The results show that the local heat transfer coefficient has an extremely large value in the thin film region. The heat transfer rate, however, is larger for the meniscus than for the thin film region. The maximum liquid velocity appears at approximately 40% of the extended meniscus region and the variation of the heat flux has a negligible effect on the maximum liquid velocity. It is also found that the length of the extended meniscus region is affected by the heat flux, the channel height and the dispersion constant.