Effect of Smooth Microchannel Cross Section Shape on Friction Factor

Pressure drop is important in performance of MEMS devices with microchannel. The geometry of microchannel will have important significant effect on of pressure drop and friction factor. The effect of four cross section shapes of microchannel on friction factors is investigated. It is found that the friction factors are significantly affected by the cross section shape. The four cross section shapes have obvious different friction factors under various hydraulic diameters. When the microchannel is triangular shape, the larger hydraulic diameter will induce more significant effect on friction factor. However, the change of hydraulic diameter has less significant effect on friction factor in rectangular microchannel. The effect of increasing hydraulic diameter is not significant and the friction factors decrease nonlinearly as the Reynold´s numbers increase