Modeling Frictional Characteristics of Water Flowing Through Microchannel

The present study aims at modeling the real random rough surface of a microchannel with structured rough channel of known geometric parameters. The surface of the microchannel is created by sinusoidal function using MATLAB code and 2D simulation of the model is carried out with commercial software ANSYS Fluent. The height of the channel is varied from 100 to 250 µm and length of the channel is 12.5 mm. The range of Reynolds number selected for analysis is 100 to 500 with water as the fluid medium. The roughness height is selected within the range of actual manufacturing roughness level of microchannels. The results show that channel geometry has significant influence on flow characteristics. A new non-dimensional roughness parameter β, is proposed to represent the dependence of friction factor on geometric parameters in the laminar region. A correlation for flow friction is developed as a function of roughness parameter and Reynolds number.