Surface topography has an important role in the motion of fluid in microchannels due to the fluid boundary layer. The cross surface roughness variations result in some problems such as turbulence, confusion in microchannel's work and in creating vortex. In this research, the topography of the floor in the microchannel is investigated experimentally. A large difference between surface topography of the sides and channel's centreline is observed. The main reason for this difference is the effect of the back cutting in trochoidal paths. A new approach is proposed to solve this problem and decrease the amount of cross surface roughness variations by eliminating the effect of back cutting. The efficiency of the proposed approach is confirmed by experiments. Scanning electron microscope images show that using this method the topography of the surface is uniformed.

Keywords