Complex Flow and Heat Transfer Behavior of Micro/nano Fluidics: Benard Convection Always Occurs in a NEMS World

摘要

In recent years, interest in the thermal-hydraulics at micro/nano scale keeps increasingly growing owning to the rapid technology thus enabled. It was now accepted that the classical thermal or fluidic theories working well for "macro bulk systems" may become invalid for micro/nano scale geometry. On the contrary, some phenomena seldom occur in the large scale may frequently happen as a routine event in the small world. This study is aimed to theoretically predict a basic phenomenon that may always be encountered in the micro/nano fluidics devices, i.e. the previously well known Benard convection cell could easily be induced in a nano scale liquid film even by an extremely small temperature difference across such layer. It is this event that increases the complexity of the flow and heat transfer patterns in the MEMS/NEMS. Fundamental mechanisms related to this phenomenon will be interpreted and its implementations for developing useful tool will be suggested