The Influence Of Surface Roughness On Flow In Microchannel

The micro-electro-mechanical-system (MEMS) is a rising multi-subject concerned research field which is mainly based on the development of micro electro and micro mechanism. MEMS is one of the most potential research subjects, and the research about micro flow system is one of the focuses. Researchers from different countries have done lots of experiments and brought forward many mathematic models to explain the micro flow phenomena. This paper is mainly about the study on the influence of surface roughness on flow in microchannel: the influence of surface roughness on fully developed stationary laminar flow and pulsation laminar flow. The theory analysis and computation simulation methods are used. The research is divided into several parts as follows:(1) The conditions for fully developed laminar channel flows in the presence of rough wall are discussed. The definition of fully developed flow with rough walls is extended as possessing periodic velocity profile along the axial direction; as a consequence of this definition. The linear relation between pressure and flux is studied theoretically.(2) The roughness models with two dimensions are established. The finite element method is used to compute for different roughness models with different roughness degree. The results for different roughness degree condition are gained and the theoretic conclusions are validated. A simple formula that is convenient for engineering is introduced to explain...