Recent Trends in the Visualization Studies of Interfacial Phenomena in Microchannels (Keynote)

Fluid flow phenomena near the liquid-solid and liquid-gas interfaces are of great interest, in conjunction with heat and mass transport in microchannels. In particular, evaporation from liquid-gas interface plays an important role in the performance of micro heat pipe, capillary pumped loop, etc. Water management and flooding control in microchannels are also well known to be crucial problems in micro fuel cells. Fluid-surface interaction under no-slip or slip condition is important in design, fabrication and operation of MEMS devices. In the present manuscript, we focus on recent advances made in the visualization studies of interfacial phenomena occurring in microchannels in terms of evaporation of liquid near the meniscus, water management and two-phase flow in micro fuel cell and near-surface velocimetry using evanescent wave illumination.