In the inner wall of aluminium microchannel

super-hydrophobic surface was fabricated.The water contact angle on the surface reached 153°.The pressure drop of water flowing in a 0.60 mm-diameter super-hydrophobic microchannel evidently decreased compared with that in super-hydrophilic microchannel

with the maximal decrease of about 25%.The flow characteristics of water in the microchannel with super-hydrophobic surface were studied.It was found that the critical Reynolds number for the transition from laminar flow to turbulent flow was approximately 2500 and in laminar flow the values of fRe were almost constant.The slip velocity and the slip length were calculated at different flow rates and the results showed that both the slip velocity and slip length increased with increasing water flow rate.